MXPA97005340A - Energy validation arrangement for a self-energized circuit switch - Google Patents

Abstract

The present invention relates to a self-energized circuit breaker arrangement for interrupting current in a circuit path using a current blocking component to ensure that an insufficient amount of accumulated energy to drive the interruption of the circuit path is not wasted in an unjustified attempt to interrupt the current path. The array includes a current-inducing circuit to provide a current signal having a magnitude corresponding to the current in the circuit path, a power source operating from the current signal provided by the current inductor and providing a voltage signal of a predetermined value relative to the common, a solenoid mechanism having a coil through which current passes from the power source to cause current interruption in the circuit path, a trip command circuit , which responds to a fault in the circuit path and includes an overload detector, to send an electrical signal that orders the circuit path to be interrupted, an electric lock actuated in response to both the electrical signal of the trip command circuit as the voltage signal that exceeds a predetermined value, the electric bolt arranged in series with the coil between the power source and the common and including a first terminal coupled to the trip command circuit and a second terminal coupled to the power source, and a prevention circuit constructed and arranged to prevent an electrical signal from the circuit trigger command or voltage signal link the electric bolt until the voltage signal exceeds the predetermined value. Various alternative arrangements are also described to overcome the problems of self-energizing a circuit breaker.

Description

ENERGY VALIDATION ARRANGEMENT FOR A ZAPO AUTO-ENERGY CIRCUIT SWITCH Field of the Invention The present invention relates to circuit interruption arrangements, and more particularly to tripping arrangements, such as circuit breakers and overload relays, which are energized from the circuit path for which they are arranged to interrupt ( self-energized). BACKGROUND OF THE INVENTION The use of circuit breakers is widespread in current residential, commercial and industrial electrical systems, and is an indispensable component of such systems to provide protection against overcurrent conditions. Various circuit breaker mechanisms have evolved and been refined over time based on specific application factors such as current capacity, response time, and type of reset function (manual or remote) desired from the circuit breaker. One type of circuit breaker mechanism employs a thermomagnetic trip device to "trip" a latch in response to a specific range of overcurrent conditions. The triggering action is caused by a considerable deflection in a bi-metal or thermostat metal element that responds to changes in temperature due to resistance heating caused by the flow of electrical current from the circuit through the element. The thermostat metal element is typically in the form of a blade and operates in conjunction with a latch so that deflection of the blade releases the latch after a time delay corresponding to a predetermined overcurrent threshold in order to break the current in the circuit associated with it. Another type of circuit interruption arrangement useful for interrupting circuits that have higher current carrying capacities, uses current transformers to induce a current corresponding to the current in the circuit path, and an electronic circuit that monitors the induced current to detect faults of energy in the circuit path. In response to the detection of a power failure, the electronic circuit generates a control signal to drive a solenoid (or equivalent device) to cause the circuit break contacts to be separated and the circuit path to be interrupted. However, it can be a problem to cause the circuit interruption contact to be separated. For example, it requires a considerable accumulation of energy, which is typically scarce in such arrangements that are self-energized, and a failed attempt to interrupt the circuit path depletes the accumulated energy reserve. This problem has been addressed to some extent by using a lower voltage shutdown circuit, which ensures that a trigger will not be initiated until the power source has sufficient power to complete the trip. However, this requires a circuit to monitor the voltage at the power source. Also, if a firing command is initiated at power-up, the firing can not be completed because the power source can not instantly deliver enough power to complete the firing. Furthermore, the failed attempt to fire will discharge that energy that has been stored in the capacitor of the power source such that it can not fully recharge before the next firing attempt, thereby causing successive firing attempts to fail as well. Accordingly, there is a need for a circuit interruption arrangement that overcomes the aforementioned limitations of the prior art devices. SUMMARY OF THE INVENTION The present invention provides a self-energized circuit breaker arrangement for interrupting current in a path without the need to monitor the voltage developed at the power source. In an implementation of the present invention, a self-energized circuit-breaker arrangement to interrupt the current in a circuit path uses a current-blocking component to ensure that an insufficient amount of accumulated energy is not wasted to drive the interruption of the circuit path in an attempt not to justified by interrupting the current path. In a specific implementation of the present invention, a circuit interruption array includes a current-inducing circuit to provide a current signal having a magnitude corresponding to the current in the circuit path; an energy source operating from the current signal provided by the current inductor and providing a signal of; relative voltage to the common; a solenoid mechanism having a coil through which the current of the power source passes to cause interruption of the current in the circuit path; a trigger command circuit, which responds to a fault in the circuit path, including an overload detector, to send an electrical signal that commands the circuit path to be interrupted; and an electric lock actuated in response to both the electrical signal of the trip command circuit and the voltage signal exceeding a predetermined value equivalent to the energy required to complete the trip. The electric bolt is arranged in series with the coil between the power source and the common one and includes a first terminal coupled to the trip circuit and a second terminal coupled to the power source. A prevention circuit is constructed and arranged to prevent one of the electrical signals of the trip command circuit and the voltage signal from linking the electric lock when the voltage signal is less than the predetermined value. The above summary of the present invention is not intended to represent each embodiment, or each aspect of the present invention. Other features and advantages of the invention will be apparent to those skilled in the art upon review of the following detailed description and drawings. Brief Description of the Drawings Figure 1 is a perspective illustration of a circuit interruption system, in accordance with the present invention. Figure 2 is an electrical block diagram of the system of Figure 1. Figure 3a is a block diagram of a self-energized overload relay that is part of the circuit interruption system of Figure 1 and incorporating the main aspects of the present invention. Figure 3b is a block diagram of a self-energized overload relay that is part of the circuit interruption system of Figure 1 and incorporating the main aspects of the present invention. Figure 4a is a schematic drawing of portions of the overload relay of Figure 3a that refer specifically to the circuit that prevents a trip attempt when insufficient energy is available in the capacitor of the power source. Figure 4b is a schematic drawing of portions of the overload relay of Figure 3b that specifically refer to the circuit that prevents a trip attempt when insufficient energy is available in the capacitor of the power source. Figure 5 is a schematic drawing of a second implementation of the circuit of Figure 4a. Figure 6 is a schematic drawing of a third implementation of the circuit of Figure 4a. Figure 7 is a schematic drawing of a fourth implementation of the circuit of Figure 4a. Figure 8 is a schematic drawing of a fifth implementation of the circuit of Figure 4a. Figures 9a-9e are illustrations of a feedback circuit used with the implementation of Figure 8. Figure 10 is a schematic drawing of an alternate implementation of the circuit of Figure 4a. Figures 11-13 are schematic drawings illustrating various implementations of the power source shown in Figure 10. Figure 14 is a schematic drawing of an implementation for extracting operating energy for the overload relay of the control circuit that The coil of the contact device operates in accordance with the present invention. Figure 15 is a schematic drawing of the implementation of Figure 14. Before the embodiments of the invention are explained in detail, it should be understood that the invention is not limited in its application to the construction details indicated in the description or illustrated in the drawings. The invention is susceptible of other embodiments and of being put into or carried out in various other ways. Likewise, it should be understood that the phraseology and terminology used herein are for the purpose of description and should not be considered as limiting. Description of the Preferred Embodiment The present invention can be used in a wide variety of residential, commercial and industrial applications. However, for brevity, the implementation of the present invention to be described and illustrated below is directed to high performance applications, which require low cost and a small package. Turning now to Figure 1, a perspective illustration of the circuit interruption system is shown in the form of an overload relay 10 and a contact device unit 12. The overload relay 10 has a set of three phase conductors 14 which They pass through openings in their accommodation. The contact device unit 12 is conventional, for example Square D class 8502, type SA012, and can be implemented to interrupt the three-phase conductors 14. The overload relay 10 includes three individual current transformers or a current transformer. three-phase 22 (shown in dashed lines) within the overload relay housing, and a manual reset button 24 for resetting the electronic circuits and the solenoid control and latch mechanism ordering the contact device unit 12 to interrupt the circuit path provided by the three-phase conductors 14. The overload contacts 18 and the auxiliary contacts 20 are provided to drive the contact device unit 12 to interrupt the current path in the conductors 14 and to provide an auxiliary alarm signal for indicate that the unit has fired, respectively. A potentiometer dial 16 is included in the overload relay housing 10 to provide the user with the ability to change the fixed point for the current trigger level within a predetermined range. In Figure 2, the overload relay 10 and the contact device unit 12 are shown from an electrical perspective, providing power to a three-phase motor 25 and having three high-level functional blocks, an energy source / overload electronics 23 , a mechanical reset 24, and a solenoid and latch mechanism 26. The power source / overload electronics 23 analyzes the current that passes to the motor 25 and links the solenoid and latch mechanism 26 so that the overload contacts 28 (at terminals 95 and 96) can open to de-energize the coil 30 of the contact device 12 if a fault is present. The mechanical reset 24 is arranged to manually reset the solenoid and lock mechanism 26 after a trip has occurred. The stop switch 32 and the latch contacts 34 in parallel with the automatic start switch 36 are conventionally implemented and are arranged to provide coil control of the contact device 30, which allows power flow to the motor 25. In this example, firing and closing consist of a mechanically held solenoid and latch mechanism 26, driven by power source 38 and activated from the overload detection circuits that are shown in block 23. When the detection circuits When the overload condition is detected, the solenoid coil is energized and this causes the mechanical movement to overcome the lock. This opens the normally closed contacts 28 in series with the coil of the contact device 30. The contact device then drops, the seal around the start button 36 is opened, and power is removed from the power source 23 of the overload relay. . The overload contacts remain in the open position via the latch mechanism 26, until the unit is restored by the mechanical resetting 24. Referring now to FIGS. 3a and 3b, the power source / overload electronics 23 of FIG. 2 is shown in greater detail. A current signal having a magnitude proportional to the current of the three-phase lines 14 is induced by current transformers 22 and the current signal is then rectified by a three-phase rectifier 42. The positive outputs of the three-phase rectifier 42 are added, via interconnection , to provide a current signal having a magnitude corresponding to the magnitude of the current in the circuit path and the current signal is used to accumulate a voltage in a power source capacitor 58 in the energy source 38. Negative outputs of the three-phase rectifier 42 are summed, via interconnection, and converted to a corresponding voltage using a load resistor 43 between the interconnection point and common (or ground). This corresponding voltage is scaled by the scaling amplifier 44 and, via quadrant 16 (of FIG. 1), the fixed point of the current trip level is adjusted using a FLA (full load amperage) adjustment potentiometer 45. A From the scaling amplifier 44, faults in the three-phase circuit path are detected using a phase loss circuit 46 and an overload detector 48. The phase loss detector 46 protects the motor against overheating when current is lost in a of the three phases (that is, it is interrupted or grossly unbalanced with respect to the other two phases). The overload detector 48 operates with an overload timer that monitors or monitors a condition of the three-phase current in which the motor 25 is taking an excessive amount of current for a predetermined period of time. The conditions of phase loss and overload may occur separately or in conjunction with one another. An engine does not necessarily have to be taking more current than normal in order to overheat in a phase-loss condition because the device only measures the current in the stator. In a phase loss condition, the current in the stator may not necessarily go over an overload condition, but the currents in the rotor that are difficult to measure will exceed the overload condition, thereby causing the motor to overheat. With reference to a stable reference voltage, set relative to the common power source for the overload relay 10, a trip level comparator SO monitors the outputs of the phase loss circuit 46 and the overload detector 48. When the trigger level comparator 50 determines that a phase loss or an overload has been detected, the trigger level comparator 50 generates a trigger signal TS using the V + of the power source 23. The trigger signal TS is directed to the solenoid driver 54, which activates the solenoid and latch mechanism 26, causing the contact device unit 12 to break the circuit path in the conductors 14 carrying current to the motor 25. For further details of the three-phase rectifier 42, scaling amplifier 44, phase loss circuit 46, overload detector 48, and firing level comparator 50, reference may be made to United States patent application Serial No. 08 / 143,948 , entitled Self-Powered Circuit Arrangement (RLC-10 / SQUC-120), filed on October 27, 1993, assigned to the same assignee as the present invention and incorporated herein by reference. By means of a lower voltage closing circuit 52, two lower voltage protection implementations are illustrated in Figures 3a and 3b. The implementation of Fig. 3a employs the lower voltage closing circuit 52 between the firing level comparator 50 and the solenoid driver 54, so that a firing signal TS sent from the firing level comparator 50 can be blocked by the lower voltage closing circuit 52 when the power source capacitor 58 has not stored a predetermined value of sufficient energy to complete the trip. The implementation of Figure 3b employs the lower voltage closing circuit 52 between the solenoid driver 54 and the solenoid and latch mechanism 26, blocking the flow of current through the solenoid and latch mechanism 26 until the source capacitor 58 has stored a predetermined value of sufficient energy to complete the trip, even though the trip signal TS may already have been triggered by the solenoid driver 54. In any case, the lower voltage closing circuit 52 ensures that there is enough energy stored in the capacitor of the power source 58 to link the solenoid and complete the trip. This is accomplished without having a monitoring circuit or monitoring of the power source to determine if there is enough voltage present to complete the trip. Figures 4a, 4b and 5 illustrate various implementations of the lower voltage closing circuit 52 corresponding to the implementations of Figures 3a and 3b. In Figures 4a, 4b and 5, the current signal from the three-phase rectifier 42 is shown as providing current for charging the energy source capacitor 58, which is sketched in Figures 4a and 4b as a 220 (or 470) capacitor microfarads. The capacitor of the power source 58 stores the necessary trigger energy and provides a source of operational power to the overload relay 10. The trigger signal TS is provided at the output of the firing level comparator 50. Referring to the figure 4a, an implementation of the circuit of Figure 3a is shown. In this implementation, a unilateral silicon switch (SUS) 52 'is used to implement the lower voltage closing circuit 52 and is placed between the firing level comparator 50 and the gate of SCR 68. The SCR 68 is used to energize the solenoid coil 70 in response to a trigger signal TS of the firing level comparator 50. The SUS 52 'is a breaking device and will not conduct until the device has its breakdown voltage therethrough. Once the SUS is driving, it has very little voltage through it (acting as a switch). Since the SUS is programmable, the device can be set to any of a variety of threshold levels, such as the voltage V + of the power source 23 which in this example is around 8 volts. Having the SUS 52 'in the circuit, the actuation of the solenoid and latch mechanism 26 is not allowed until the capacitor of the power source 58 has sufficient charge to complete the firing. When the trigger level comparator 50 generates the trigger signal TS, the SUS 52 'will not conduct until the voltage level of the trigger signal TS exceeds the breakdown voltage of the SUS 52', which is selected to be equal to V +. When the breaking level is reached, the SCR 68 is biased to on, thereby causing current flow through the solenoid 70 and causing the current in the three-phase circuit path to be interrupted. A diode 80 is arranged as a rear diode for the coil 70 so as to provide a path for the coil current to continue to flow when the SCR 68 is turned off and to avoid the high inductive recule voltage, that otherwise would happen. A pair of resistors 82 and 84, together with a capacitor 86, provide adequate polarization for the SCR 68. Referring to FIG. 4b, an implementation of the circuit of FIG. 3b is shown. In this implementation, a one-sided silicon switch (SUS) 52§ was used to implement the lower voltage closing circuit 52 and is placed in series with the current discharge point of the capacitor of the power source 58, the coil 70 and the input terminal of SCR 68. The SUS $ 52, again having a threshold level equal to V + of the power source 23, will not lead until the voltage of the capacitor of the power source 58 is sufficient to complete the shot. When the trigger signal TS of the firing level comparator 50 is present, the signal in the gate of the SCR 68 will force the SCR 68 to activate. However, the SCR 68 will not conduct until the breaking voltage of the SUS 52 is reached. $. In an exemplary embodiment, the following component values are used for the circuits of Figures 4a and 4b: resistor 82: 682 Ohm capacitor 58: 470 μF resistor 84: 1 kOhm capacitor 86: 0.47 μF and the SUS can be implemented using a 2N4989 type component available from Motorola or Harris. Referring to Figure 5, a second implementation of the circuit of Figure 3a is shown. In this implementation, the unilateral silicon switch (SUS) 52 'is replaced by two voltage dividers, an accretion mode FET (field effect transistor) 96 and a bipolar 98 transistor. The trigger signal TS (V +) of firing level comparator 50 is provided to the potential splitter, including resistors 102 and 104 in an attempt to turn on FET 96. FET 96 will not conduct until the gate voltage of the potential divider is sufficient to turn it on. With no drain current flowing in the FET 96, the transistor 98 will not be activated, thereby preventing the collector current from flowing out of the transistor 98. Without collector current flowing in the transistor 98, the SCR 68 can not be activated, which prevents the coil 70 from being activated. The values of resistors 102 and 104 of the potential divider are selected such that the appropriate gate voltage to activate the FET 96 is provided when the capacitor of the power source 58 has enough voltage to complete the shot. When sufficient voltage is present in the gate of the FET 96, the FET 96 will conduct and cause the transistor 98 to activate and provide a drive signal to the potential splitter, including the resistors 110 and 112 so as to drive the SCR 68 to pull current through the coil 70. A pair of resistors 114 and 116 are used to properly bias the base of the transistor 98 in response to the actuation of the FET 96. In an exemplary embodiment, the following component values are used for the components Unique to the circuit of figure 5: resistor 102: 93.1 kOhm resistor 114: 10 kOhm resistor 104: 10 kΩ ohm resistor 116: 98.7 kΩ ohm resistor 112: 1 kΩ ohm capacitor 58: 470 μF and the FET 96 can be implemented using a 2N7000 type component available from Motorola. Referring now to Fig. 6, a third implementation of the lower voltage closing circuit 52 of Fig. 3a is outlined. This implementation further includes a terminal 120 of the load resistor 43 fed from the interconnection of the negative outputs of the three-phase rectifier 42 (of FIG. 3a) to an input of the closing circuit 52. Rather than using a SUS or an FET for preventing the solenoid coil 70 from being activated, as discussed in relation to Figures 4a, 4b and 5, the implementation of Figure 6 is based on the magnitude of the current in the three-phase conductors to determine a period of time delay enough before starting and / or repeating a shot attempt. The time delay depends on the current present in the secondary circuit of the current transformer, because this current is used to accumulate the stored energy that is used to link the firing mechanism. As this current increases, the time required to store the necessary trigger energy decreases, and as this current decreases, the time required to store the necessary trigger energy increases. For a typical protective device, for example a small, self-energizing, adjustable-range electronic overload relay, it would take about 75% of the total load amperage (FLA) at the minimum range set to activate electronic circuits, while the minimum current that a shot could wish would be above 100% of the minimum FLA. The current transformers 22 used in such a device are designed to produce sufficient secondary current to activate the electronic circuits at 75% of the minimum FLA. This current is used to charge the capacitor of the power source 58 which provides the necessary tripping energy. In this way, the time required to store the energy required for a successful trigger is different and depends on the amount of current flowing in the secondary of transformer 22, and a circuit using such a time delay requires that the delay of time is variable and set according to the secondary current level of the transformer 22. In Fig. 6, the voltage present in the terminal 120 is directly proportional to the secondary current of the current transformers 22 and its voltage can be used to control the charge rate of a 12-shot delay capacitor. The trip delay capacitor 124 is charged with a current that is small compared to the current that is available to charge the capacitor of the power source 58. This minimizes the impact on the time required to charge the capacitor of the power source. energy 58, thereby minimizing any additional time delay added before sufficient firing energy is stored by the capacitor of the power source 58. Referring to the upper left portion of FIG. 6, the resistors 131, 132, 133 and 134, the operation amplifier 135, and the transistor 136 are arranged to provide a voltage controlled current source. The values of resistors 131, 132, 133, 134 are selected to provide the required current corresponding to the voltage at terminal 120. In a conventional voltage controlled current source configuration, a similar arrangement is used but with the base of the transistor 136 directly connected to the common (earth). A reference diode (or Zener) 138 is used in place of a direct connection to ground to increase the available voltage in the collector of transistor 136 to more than a threshold of 1.25 volts (V1-2), which will be required in the trigger delay capacitor 124 before a trip can occur. The voltage across the capacitor 124 increases at a rate that is proportional to the voltage output at the terminal 120, which, in turn, is proportional to the current in the secondary of the current transformers 22. Therefore, the charge rate of the trip delay capacitor 124 is proportional to the current in the secondary of the current transformer 22. When the voltage across the trip delay capacitor 124 reaches the reference level of 1.25 volts, the output of the comparator 146 swings high, ordering the solenoid driver circuit 54 to link the solenoid and interrupt the current in the three-phase circuit path. A transistor 148 and resistors 150 and 156 are used to initiate the delay when a trigger request has been signaled by the trigger signal TS of the trigger level comparator 50. An active, high trigger request signal is inverted by a pair of resistors 160 and 162 and a transistor 164c. , so that the trigger request signal is suitable for driving the base of transistor 148. When the trigger request signal is received, transistor 164 is activated and this turns off transistor 148. This allows the source current of voltage-controlled current charge the trip delay capacitor 124, which provides the appropriate time delay for the comparator 146. Preferably, the trip signal TS is received to indicate that a phase loss or overload has been detected. For example, a TS trip signal provided by the circuits illustrated and described in the United States Patent Application Serial No. 08/143, 948, entitled Self -Powered Circuit Interruption, is suitable.

Arrangemen t. A diode 170 is included to prevent the time delay capacitor 124 from accidentally discharging if the trigger signal TS generated by the firing level comparator 50 becomes momentarily inactive, thereby activating transistor 148. This would give result in an undesirable additional delay condition. When a trip occurs, the trip delay capacitor 124 must be fully discharged to restore the delay function. The feedback from the output of the solenoid driver 54 is used to control the base of a transistor 174, via the base resistors 176 and 178, to discharge the discharge delay capacitor 124 immediately after a trigger has been initiated. The solenoid driver 54 maintains its high output for a period of time sufficient to both link the trip solenoid and to discharge the trip delay capacitor 124. A resistor 180 has a value that is selected to discharge the trip delay capacitor 124 at a rate equivalent to the rate at which the energy source capacitor 58 is discharged by the energization of the overload relay circuits. For example, if the current drawn by the overload relay circuits is around 0.5 milliamperes and the value of the power source capacitor 58 is 220 microfara-god, then the value of the resistor 180 can be selected to be 5.28 kOhms for a tripping voltage of 1.2 volts, assuming that the value of the capacitor 124 is 100 microfarads. In another embodiment, a one-shot timer 184 (shown in dashed lines) and diodes 187 and 188 are inserted between the output of the firing level comparator 50 of Figure 3a and the solenoid driver 54. Diodes 187 and 188 are linked to OR logic gate so that both the timer of a shot 184 and the comparator 146 can drive the solenoid driver 54. Using the one-shot timer 184 in this manner causes the solenoid driver 54 to make a first attempt to fire the unit immediately after the firing level comparator 50 generates the trigger signal TS, and if this attempt was not successful, fall back into the normal time delay routine described above. In an exemplary embodiment, the following values are used for the components shown in the circuit of Figure 6: resistor 131 17 kOhm resistor 160 120 kOhm resistor 132 17 kOhm resistor 162 100 kOhm resistor 133 17 k ohm resistor 176 120 k ohm resistor 134 17 kOhm resistor 178 100 kOhm resistor 137 100 kOhm resistor 180 selected as described resistor 150: 120 kOhm capacitor 124: 100 μF resistor 156: 120 kOhm and comparators 50 and 146 can be implemented using a component type 0O290GP available from Analog Devices, Inc. Referring now to Figure 7, a fourth implementation of the lower voltage shut-off circuit 52 of Figure 3a is outlined. In this implementation, rather than monitoring the voltage directly on the capacitor of the power source 58, the voltage accumulated in the capacitor of the power source is modeled using a modeling capacitor 200 and a trigger enable signal TE is provided when enough energy has been stored. The voltage developed on the modeling capacitor 200 depends on the current present in the secondary circuit of the current transformer 22, because this current is used to accumulate the stored energy used to link the firing mechanism. As this current increases, the energy storage rate increases; and, as this current decreases, the energy storage rate decreases. For this reason, the voltage present in the terminal 120 (also shown in the alternate embodiment of Fig. 6) is brought directly to the voltage controlled current source, using the same circuits shown in Fig. 6 and including the amplifier of operations 135, resistors 131-134 and 137, transistor 136, and Zener diode 138.

The voltage controlled current source uses the voltage at terminal 120 to control the charging rate of the modeling capacitor 200 providing a current that is small compared to the current that is available to charge the capacitor of the power source 58. this way, there is a minimal impact on the time required to charge the capacitor of the power source 58, thereby minimizing any additional delay added before sufficient firing energy is stored. The voltage across the capacitor 200 increases at a rate that is proportional to the current that is given as the output of the current source, which is proportional to the voltage at terminal 120, which is proportional to the current in the secondary of the current transformers 22. Thus, the charge rate of the capacitor 200 is proportional to the current in the secondary of the current transformer 22, and when the voltage across the capacitor 200 reaches the reference of 1.2 volts in the input terminal positive of an open collector comparator 204, the output of the comparator 204 changes from an active to an inactive state, providing the trigger enable signal TE. The output of the comparator 204 indicates to the solenoid driver 54 that the power supply capacitor 58 has stored enough energy to successfully link the trip solenoid. The solenoid driver 54 also provides a discharge control signal to a transistor 208, via bias resistors 210 and 212, which discharges the capacitor 200 when a trip occurs. A resistor 214 is used to discharge the capacitor 200 at a rate that is equivalent to the rate at which the capacitor is discharged from the power source 58 by energizing the overload relay circuits. The solenoid driver 54 is therefore instructed to operate the solenoid via the trigger signal TS of the firing level comparator 50, as discussed in relation to FIG. 6, and via a diode 218, a resistor 206 and the output of the comparator 204. The trip signal TS is prevented from controlling the solenoid driver 54 by the trip enable signal TE of the output of the open collector comparator 204 when the voltage in the capacitor 200 is less than 1.2 volts. In an exemplary embodiment, the following component values are used for the unique components shown in the circuit of Figure 7: resistor 206: 100 kOhm resistor 212: 100 kOhm resistor 210: 120 kOhm capacitor 200: 100 μF Resistor 214 it is selected in the same way as the resistor 180 of FIG. 6. Referring now to FIG. 8, a fifth implementation of the lower voltage closing circuit 52 of FIG. 3a is outlined. This implementation ensures a successful trip cycle without measuring the voltage of the power supply capacitor 58. In this implementation, a short pulse of current is sent to the solenoid coil 232, immediately after which the solenoid state is evaluated using one of different types of feedback. Based on this solenoid feedback, a failed trip attempt can be detected and the trip can be attempted again after the capacitor of the Cps power source has been fully recharged. When the solenoid link switch (shown in Figure 8 as a FET 230) is active, the capacitor of the power source Cps is discharged into the solenoid coil 232, driving the mechanism and executing a trip. The FET 230 is forced into active state whenever TRIP or TRIPF is in the high state by connecting these signals to the gate of the FET 230 via the diodes 236 and 238. The TRIP or TRIPF signals are controlled using: a centered timing function around an operation amplifier 240; a trigger arbitration function including a comparator 242; a solenoid feedback bolt function including the amplifier 244; and a solenoid feedback control signal FDBK provided using one of the circuits shown in Figures 9a-9e. Each of the comparators shown in Figure 8 can be implemented using a LM311 type component or the like. The timing function involves using the operation amplifier 240, together with the diodes 250 and 252, a capacitor 254 and resistors 256, 258, 260 and 262, to provide a square wave output of variable duty cycle, of run continuous TF, having a period of about one second and consisting of a brief high level pulse followed by a relatively long low level pulse. Provided that the square wave is in high state, the FET 230 is active, provided that the high level trigger request signal at the input of the tri-state compensator 270 is present. The amplifier 240 can be implemented using, for example, the amplifiers type operations available from Analog Devices, Inc. The duration of the high level pulse at the output of the amplifier 240 is selected to provide sufficient system load to develop the feedback signals of the amplifier. Solenoid associated with Figures 9a-9e without draining the capacitor from the Cps power source to an intolerably low level, which would require a long recharge time. The time between the high level pulses is selected to allow the capacitor of the power source Cps sufficient time to recharge at a minimum load current before attempting a subsequent trip. The arbitration function of; triggering involves forcing the FET 230 to the active state as long as the output of the comparator 242 (TRIP) is high. This occurs when the timer output of the operation amplifier 240 is high and the trigger request signal forces the tri-state comparator 270 to the enable (high impedance) state. Otherwise, the output of the comparator 242 is in the low state. A pair of voltage division resistors 282 and 284 are used to provide a reference signal around which the comparator 242 detects the level of the signal output of the tri-state comparator 270. With respect to the latch function of Solenoid feedback, the amplifier 244 acts as a latch to maintain the TRIPF signal in the high state when the FDBK signal at the negative input terminal of the amplifier 244 is high and the output of the amplifier 240 is high. The voltage division resistors 286 and 288 are used to provide a reference signal around which the comparator 244 detects the level of the signal at its negative input terminal. A diode 274 is in series with a line between the FDBK signal, via a resistor 276, and the negative input terminal 244, via a diode 278, to ensure that the output of the amplifier 244 is disabled if the output of the amplifier 240 is low. . When the overload relay 10 is activated, an activation reset circuit 289 is used to control the negative input terminal of the comparator 244 at a high level until the capacitor of the power source Cps develops full load to operate the power relay. overload 10. This keeps the output of the receiver 244 at the low level, thereby preventing a false trigger request signal from controlling the FET 230. The solenoid feedback signal FDBK, provided using one of the circuits of FIGS. 9a-9e , indicates that there is sufficient power for the contact device to successfully complete the interruption of the three-phase circuit path in response to an attempted interruption initiated by the brief high-level pulse of the square-wave, variable duty cycle output TF in conjunction with the high-level trigger request at the input of the tri-state comparator 270. In each of the circuit of Figures 9a-9e, the FET 230 of Figure 8 is functionally illustrated in Figures 9a-9e as a switch 298 (for example, a relay, SCR or bipolar transistor circuit). In addition, the solenoid coil 232, the capacitor of the power source Cps and the solenoid plunger 300 are shown as in Figure 8. Referring now to Figure 9a, the solenoid feedback circuit is shown using a pair of mechanical contacts 304 and 306. The contact 304 is physically attached to the plunger 300 such that it moves with the plunger 300 while the contact 306 is fixed so that it does not move with the plunger 300 and a predetermined distance is separated away from the contact 304 when the plunger 300 is in the non-energized position. When the solenoid coil 232 is energized to complete the trip, the plunger 300 is pushed forward with sufficient speed to cause the contacts 304 and 306 to close within a predetermined time (high-level pulse duration of the timing circuit), thereby producing a FDBK solenoid feedback signal indicating that there is sufficient energy stored in the capacitor of the Cps power source to complete the trip. If the energy stored in the capacitor of the power source Cps is not sufficient to complete the trip, the contacts 304 and 306 will not close within the predetermined time and the solenoid feedback signal FDBK will indicate that there is insufficient energy stored in the capacitor. of the Cps power source to complete the shot. In case there is insufficient energy stored in the capacitor of the power source Cps to complete the trip, a pull resistor 308 will ensure that the FDBK solenoid feedback signal remains high, thereby aborting the firing attempt at the start of the pulse Low level of the square wave output of variable duty cycle TF. This action will prevent the capacitor of the Cps energy source from being completely discharged and will reduce the time required for the total recharge of the capacitor from the Cps energy source. In Figure 9b, the solenoid feedback function is provided by monitoring or monitoring the actual current of the solenoid through the coil of the solenoid 232. The current in the coil of the solenoid 232 rises approximately linearly during the early stages of a solenoid. real shooting event. In this way, if the current is above a selected minimum threshold value for a prescribed period of time, selected so that the current rises to the upper limit of the linear rail, then the capacitor of the power source Cps has sufficient energy to complete the shot. A resistor 310 is used in series with the coil 232 and the switch 298 to develop a corresponding voltage that is used by a conventional amplifier circuit, including the operation amplifier 312 and the resistors 314 and 316 to provide the feedback signal of the FDBK solenoid to the circuit of Figure 8. In Figure 9c, the solenoid feedback function is provided by monitoring the flow developed as current sent through the solenoid coil 232. The flow links are a function of the current flowing in the Solenoid coil 232 and the position of the plunger 300 relative to the coil 232. By pulling the plunger 300 further into the solenoid coil 232 by increasing the current flow in the coil 232, the flow is increased. Therefore, the force (energy stored in the capacitor of the power source Cps) that drives the solenoid is proportional to the magnetic flux. A signal proportional to the flow can be generated by integrating the signal derived from a coil of sensor windings 320 wound around the plunger 300. The output of the coil of sensor windings 320 is connected to an operation amplifier 322 using a resistor 324 and a capacitor 326 arranged to integrate the input and to generate an output signal proportional to the flow. If the signal is over a selected minimum threshold value during the high-level pulse of the square wave output of variable duty cycle TF, the system has enough power to complete the shot. The operation amplifier 322 can be implemented using a single source operations amplifier by selecting the polarity of the sensing voltage of the coil of sensors windings 320 to be negative. In Figure 9d, the solenoid feedback function is provided using a coil of sensor coils 330 to monitor the rate at which the flow is rising as current is sent through the solenoid coil 232. The voltage Vs across the the output of the coil of sensor windings 330 is proportional to the rate at which the flow in the circuit is rising. If the flow rise is large enough during the high-level pulse of the variable duty cycle square wave output TF, the system has enough power to complete the trip. The coil of sensor windings 330 is implemented such that it does not create a simple transformer and, therefore, indirectly measures only the capacitor voltage of the power source Cps. The signal produced at the output of the coil of sensor windings 330 is proportional to the voltage of the capacitor of the voltage source Cps minus the drop, of the resistive voltage of the coil of the solenoid 232. Therefore, the coil of sensor coils 330 produces a voltage directly proportional to the capacitor of the power source Cps only during the first instant after the switch closes. This proportional voltage is then amplified using an operation amplifier 334 having an amplification factor set by the resistors 336 and 338. In Fig. 9e, the solenoid feedback function is provided by monitoring a signal proportional to the motor current, which is available in the load that requires the shot. One way to obtain the signal proportional to the motor current is to use the terminal 120 of the interconnection of the negative outputs of the three-phase rectifier 42 (shown in FIG. 3a). By conditioning the signal at terminal 120 using a current blocking diode 340 and a conventional resistor-capacitor network filter 341, a comparator 344 can compare the signal with a reference voltage developed between the voltage divider resistors 346 and 348. normal run conditions, for example greater than 30% of the minimum current, the negative input of the comparator 344 is greater than the reference voltage in the positive input and the output signal FDBK is low. When a successful trigger can be achieved, the voltage at terminal 120 drops to a negligible level and the output from comparator 344 changes state to a high level, thereby signaling that a successful trigger will occur. Accordingly, the solenoid is activated using the FDBK signal through the diode OR logic established by diode array 236 and 238 (FIG. 8) whenever TRIP is high, indicating a properly timed trigger request, or TRIPF is high , indicating that enough energy has been accumulated before a re-firing attempt occurs. Turning now to Figure 10, another approach to overcome the problems associated with the auto-energization of an electronic overload relay is illustrated. A considerable advantage with this approach is that current transformers are not required to develop the power source as well as to maintain a reasonable accuracy of the measured current. Rather, current transformers are only required to measure the current in the three-phase circuit path, thereby significantly reducing the size and cost of current transformers for the same accuracy requirements. Since current transformers are major components, the size and cost of the full overload relay are substantially benefited. The benefit is particularly noticeable at low current levels (for example, ARMS of the motor current and minors). Furthermore, in order to maintain the size and cost of the current transformer at reasonable levels, the electronic circuit must minimize the amount of current required from the power source. At low motor current ranges, the amount of current taken by electronic circuits is so low that it is typically impractical to even excite light-emitting diodes (LEDs) to indicate whether the unit is active or if it is in the triggered condition. The approach in Figure 10 solves these problems, so long as the approach: does not require a separate power source and does not require additional electrical connections; minimize the size and costs of current transformers, thereby reducing the size and cost of the entire unit; and provide enough power to operate indicative LEDs. Because enough energy is available to excite indicative LEDs, one or more LEDs can be used to indicate active, running or non-triggered conditions. The arrangement of Fig. 10 includes a power source 350 for extracting energy from the three-phase circuit path using the connections between the conductors 14 (of Fig. 1) and the overload relay 10 (of Fig. 1). The array further has an electronic control 352 which includes the arrangement of FIG. 3a minus the power source 38 and the lower voltage closing circuit 52. For this arrangement, the overload relay 10 would have input and output terminals (not shown) to be in interface with the conductors 14, unlike transverse passage windows, as shown in Figure 1. In this way, the arrangement shown in Figure 3a is modified by taking current for the energy source 38 directly from the input or output terminals that connect the three-phase circuit path with the overload relay 10, and eliminating the need for the closing circuit 52. The trip command generated to drive the solenoid is divided into voltage by the resistors 353 and 354 for controlling a switch 355 (shown as a bipolar transistor), which in turn draws power through the solenoid coil (or relay) 356. A diode 357 is used; It was previously described. In one embodiment, the power source can be implemented as shown in Figure 11, using the available line-to-line motor voltage via the input and output terminals of the overload relay (not shown). In this case, the voltage of the three phases is rectified via a three-phase rectifier 360 to ensure that the overload still operates if any of the three phases is lost. The rectified voltage at the output of the rectifier 360 is applied to a shielding Zener diode 362 with a resistor 364 and a capacitor 366 disposed and selected in value to minimize the wattage dissipated in the resistor 374 while still maintaining a reasonable time constant to establish the source of energy. For a range of overload relays that can operate from 230 to 600 VRMS, three phases, the value of the resistor 364 can be selected from 1 megaOhm and the capacitor 366 to 100 microfarads to give an energy dissipation in the resistor 364 of less than 1 watt at 600 volts and still maintain a time constant of 1.5 seconds at 230 volts. In the embodiment of Figure 12, the power source 350 is shown using a single line 370 connected to one of the three-phase conductors 14. A diode 372 is used to rectify the current taken by the line 370 and charge a capacitor the power source 374 for supplying voltage Vps of the power source for the electronic control 352 of Figure 10. By plugging the capacitor 374 via a resistor 375, a light emitting diode (LED) 376 is used to indicate the presence of power to the user of the system. The embodiment of Fig. 13 also shows the power source 350 using a single line 370 which is connected to one of the three-phase conductors 14. Instead of the capacitor 374 and the resistor 375 of Fig. 12, an amplification regulator 380 , such as the Lambda 6350 switching regulator and associated passive components, is used to provide the regulated supply voltage Vps. When considering the advantages and disadvantages of each of these implementations, the implementation of the power source 350 of Figure 11 will continue to operate after one of the phases has been lost, while the implementation of Figures 12 and 13 depends on the phase current connected to line 370. The arrangements of figures 14 and 15 illustrate a modification of the arrangement shown in figure 2, in accordance with the present invention, to extract operating energy from the control circuit that operates the coil of the contact device 30. In Figure 14, the power source 390 for the overload relay is arranged in series with the contacts of overload (terminals 95 and 96), and overload detection circuits 392 are a separate circuit block that operates from the energy drawn via the power source 390. Figure 15 illustrates the power source 390 including two Zener diodes 396 and 398 (of equal nominal voltage ratings) placed back to back in series between the customer terminals 95 and 96 to avoid applying a voltage to the coil 30 with a direct current shift. The output voltage connection of the power source Vps is made between the overload contacts 28 and the Zener diode 396, via a diode 400, to charge a capacitor 402. Due to the additional power provided by this arrangement, a LED 404 as activation indicator. Instead of the combination of the resistor 406 and the capacitor 402, an amplification regulator (such as 380 of FIG. 13), which responds to low voltage and high current levels, can be used to provide the output + Vps having levels Low current and high voltage. Since the power source 390 is in series with the coil of the contact device 30, it is preferably designed so that a considerable voltage is not taken from the coil of the contact device 30, thereby affecting the take and fall levels ( voltage or time) of the contact device. Also, power source 390 is preferably designed to handle the coil current of the contact device (including the high torrent current associated with the tap) without over-dissipation. In an exemplary application, this circuit of FIGS. 14 and 15 will operate with coil voltages of the contact device ranging from 120 to 600 VAC in a range of contact device sizes of sizes NEMA 00 to 3, with the overload contacts 28 implemented using Aromat STIE-L2-DC5V or equivalent, Zener diodes 396 and 398 implemented using a 5-volt, 5.1-volt, 1N5338B component, providing a DC voltage for power source 390, and capacitor 402 implemented using a 100 μF electrolytic capacitor. Accordingly, various auto-energized circuit interruption arrangements have been disclosed, each incorporating the principles of the present invention and providing high-range performance in terms of selectivity of the current transformer and accuracy in detecting fault conditions. Those skilled in the art will readily recognize that various modifications and changes may be made to the present invention without strictly following the exemplary circuits illustrated and described herein. For example, various combinations of the above-described circuits can be used to overcome the problems associated with self-energizing an overload relay, and a variety of interchangeable components can be used in place of the circuits shown. Such changes would not depart from the true spirit of the present invention, which is pointed out in the following claims.

Claims (53)

1. A circuit breaker arrangement for interrupting current in a circuit path, comprising: a current-inducing circuit for providing a current signal having a magnitude corresponding to the current in the circuit path; an energy source operating from the current signal provided by the current-inducing circuit and providing a voltage signal relative to the common; a solenoid mechanism having a coil through which current passes from the power source to cause interruption of the current in the circuit path; a trigger command circuit, responding to a fault in the circuit path and including an overload detector, for sending an electrical signal that commands the circuit path to be interrupted; an electric bolt driven in response to both the electrical signal from the firing command circuit and the voltage signal exceeding a predetermined value, the electric bolt arranged in series with the coil between the power source and the common and including a first terminal coupled with the trigger command circuit and a second terminal coupled to the power source; and a prevention circuit constructed and arranged to prevent one of the electrical signals from the trip command circuit or the voltage signal from linking the electric bolt until the voltage signal exceeds the predetermined value.

2. A circuit breaker arrangement, according to claim 1, wherein the prevention circuit is arranged in series with the firing command circuit and the first terminal of the electric bolt.

3. A circuit breaker arrangement, according to claim 1, wherein the prevention circuit is arranged in series with the coil, the power source and the second terminal of the electric bolt.

4. A circuit breaker arrangement, according to claim 2, wherein the prevention circuit includes a unilateral silicon switch.

5. A circuit breaker arrangement, according to claim 3, wherein the prevention circuit includes a unilateral silicon switch.

6. A circuit breaker arrangement, according to claim 2, wherein the prevention circuit includes an FET.

7. A circuit breaker arrangement, according to claim 1, wherein the electric bolt includes an SCR.

8. A circuit breaker arrangement, according to claim 1, wherein the trip command circuit further includes a phase loss detector.

9. A circuit breaker arrangement for interrupting current in a multi-phase circuit path, comprising: a current circuit, including a plurality of current transformers and at least one rectifier, to provide a current signal having a magnitude corresponding to the current in the circuit path, each current transformer inducing current from the multi-phase circuit path respectively; an energy source including a capacitor charged to a predetermined value from the current signal provided by the current circuit and providing a voltage signal relative to the common; a solenoid mechanism having a coil through which current passes which is discharged from the capacitor to cause interruption of the current in the circuit path; a trigger command circuit, responding to a fault in the circuit path and including an overload detector, for sending an electrical signal that commands the circuit path to be interrupted; an electric bolt driven in response to both the electrical signal of the trip command circuit and the voltage signal exceeding the predetermined value, the electric bolt arranged in series with the coil between the power source and the common and including a first terminal coupled with the trigger command circuit and a second terminal coupled to the power source; and a prevention circuit, constructed and arranged in series with the firing command circuit and the first terminal of the electric bolt to prevent the electrical signal of the firing command circuit from linking the electric bolt until the voltage signal exceeds the value predetermined.

10. A circuit breaker arrangement, according to claim 9, wherein the prevention circuit includes a unilateral silicon switch.

11. A circuit breaker arrangement, according to claim 9, wherein the prevention circuit includes an FET.

12. A circuit breaker arrangement, according to claim 9, wherein the electric bolt includes an SCR.

13. A circuit breaker arrangement, according to claim 9, wherein the circuit command circuit further includes a phase loss detector.

14. A circuit breaker arrangement for interrupting current in a multi-phase circuit path, comprising: a current circuit, which: includes a plurality of current transformers and at least one rectifier, to provide a current signal having a current magnitude corresponding to the current in the circuit path, each current transformer inducing respectively current from the multi-phase circuit path; an energy source including a capacitor charged to a predetermined value from the current signal provided by the current circuit and providing a voltage signal relative to the common; a solenoid mechanism having a coil through which current passes which is discharged from the capacitor to cause interruption of the current in the circuit path; a trigger command circuit, responding to a fault in the circuit path and including an overload detector, for sending an electrical signal that commands the circuit path to be interrupted; an electric bolt driven in response to both the electrical signal of the trip command circuit and the voltage signal exceeding the predetermined value, the electric bolt arranged in series with the coil between the power source and the common and including a first terminal coupled with the trigger command circuit and a second terminal coupled to the power source; and a prevention circuit constructed and arranged in series with the coil and power source to prevent the electric lock from being engaged until the voltage signal exceeds the predetermined value and the electrical signal from the trip command circuit is present in the first terminal.

15. A circuit breaker arrangement, according to claim 14, wherein the prevention circuit includes a unilateral silicon switch.

16. A circuit breaker arrangement, according to claim 14, wherein the electric bolt includes an SCR.

17. A circuit breaker arrangement, according to claim 16, wherein the first terminal is a terminal gate to which a voltage is applied to activate the SCR.

18. A circuit breaker arrangement, according to claim 14, wherein the trip command circuit further includes a phase loss detector.

19. A circuit breaker arrangement for interrupting the current in a circuit path, comprising: a current-inducing circuit for providing at least one current signal having a magnitude corresponding to the current in the circuit path; an energy source that includes a capacitor that is being charged to a predetermined value for a prescribed minimum period of time, the power source operating from said at least one current signal provided by the current-inducing circuit and providing a signal of relative voltage to the common; a trip command circuit, "which responds to a fault in the circuit path, to send an electrical signal that orders the circuit path to be interrupted using the voltage signal provided by the power source; an electric bolt driven in response to the electrical signal of the firing command circuit; and a control circuit responsive to said at least one current signal provided by the current-inducing circuit, arranged to prevent the electrical signal from binding the bolt until after the prescribed minimum period of time. A circuit breaker arrangement, according to claim 19, wherein said at least one signal includes a first coupled current signal for charging the capacitor and a second coupled current signal for driving a voltage controlled current source. 21. A circuit breaker arrangement, according to claim 20, wherein the voltage controlled current source is arranged to charge a trip delay capacitor. 22. A circuit breaker arrangement, according to claim 21, wherein the voltage controlled current source is arranged to charge the trip delay capacitor at a rate proportional to the magnitude of the first current signal. 23. A circuit breaker arrangement, according to claim 21, further comprising a feedback circuit that responds to the trip command circuit, to completely discharge the trip delay capacitor immediately after the circuit path is interrupted. . 24. A circuit breaker arrangement, according to claim 20, wherein the voltage controlled current source is arranged to charge a modeling capacitor at a rate proportional to the magnitude of the first current signal. 25. A circuit breaker arrangement, according to claim 24, further comprising a circuit for completely discharging the modeling capacitor immediately after the circuit path is interrupted. 26. A circuit breaker arrangement, according to claim 19, further comprising a timer circuit of a draft arranged and constructed to bypass the control circuit and initiate a first firing attempt immediately after the firing command circuit sends the electrical signal that orders the circuit path to be interrupted. 27. A circuit breaker arrangement, according to claim 19, wherein the trip command circuit further includes an overload detector. 28. A circuit breaker arrangement, according to claim 19, wherein the trip command circuit further includes a phase loss detector. 29. A circuit arrangement for interrupting current in a circuit path, comprising: a current-inducing circuit for providing a current signal having a magnitude corresponding to the current in the circuit path; an energy source operating from the current signal provided by the current-inducing circuit and providing a voltage signal relative to the common; a trigger command circuit, responding to a fault in the circuit path, for sending an electrical signal that commands the circuit path to be interrupted using the voltage signal provided by the power source; a circuit interrupting circuit, which includes a circuit breaker mechanism, driven in response to the trip command circuit when the power source has provided the voltage signal at a magnitude sufficient to drive the circuit interruption mechanism; a timing circuit that produces a current pulse having a particular high level duration and a particular low level duration; a solenoid feedback circuit, which responds to a mechanical or electrical change in the circuit interruption circuit caused by the high-level duration of the current pulse of the timing circuit; and a feedback-controlled circuit, which responds to a signal from the solenoid feedback circuit, to selectively cause the electrical signal of the trip command circuit to be continued or discontinued. 30. A circuit breaker arrangement, according to claim 29, further comprising a first mechanical contact and a second mechanical contact being separated from the other by a predetermined distance during the duration of the low level pulse of the timing circuit. A circuit breaker arrangement, according to claim 30, wherein the first mechanical contact responsibly responds to the operation of the circuit breaker mechanism during the high-level duration of the current pulse of the timing circuit and the second contact mechanical is fixed with respect to the operation of the circuit interruption mechanism during the high-level duration of the current pulse of the timing circuit. 32. A circuit breaker arrangement, according to claim 31, wherein the first mechanical contact is fixed to a solenoid plunger of the interrupting mechanism such that the solenoid plunger movement during the high-level duration of the current pulse of the timing circuit causes movement of the first mechanical contact in the direction of the second mechanical contact. 33. A circuit breaker arrangement, according to claim 32, wherein the closing of the first and second mechanical contacts before the high-level duration of the current pulse of the timing circuit is completed produces a high output signal from the solenoid feedback circuit, causing the feedback controlled circuit to continue the electrical signal of the trip command circuit, thereby completing the trip. 34. A circuit breaker arrangement, according to claim 32, wherein the failure to close the first and second mechanical contacts before the high-level duration of the current pulse of the timing circuit is completed produces a low output signal of the circuit of solenoid feedback, causing the feedback-controlled circuit to discontinue the electrical signal from the trip command circuit, thereby aborting the trip. 35. A circuit breaker arrangement, according to claim 29, wherein the solenoid feedback circuit includes a circuit arranged and constructed to monitor the rate at which the current drawn from the power source is raised to drive the operating mechanism. circuit interruption during the high-level duration of the current pulse of the timing circuit. 36. A circuit breaker arrangement, according to claim 35, wherein the solenoid feedback circuit includes a resistor and a conventional operating amplifier circuit to determine whether the supervised or monitored current has been raised above a selected minimum threshold value and thereby generate a high output signal to the feedback controlled circuit if the monitored current is above a minimum threshold value or low output signal if the monitored current is below the minimum threshold value. 37. A circuit breaker arrangement, according to claim 29, wherein the solenoid feedback circuit includes a circuit arranged and constructed to monitor or monitor the electromagnetic flow developed in response to the current drawn from the power source to drive the circuit breaker mechanism during the high-level duration of the current pulse of the timing circuit. 38. A circuit breaker arrangement, according to claim 37, wherein the solenoid feedback circuit includes a coil of sensor windings wound around a solenoid plunger of the circuit breaker mechanism to detect the electromagnetic flow in the solenoid during the high-level pulse of the timing circuit. 39. A circuit breaker arrangement, according to claim 38, wherein the solenoid feedback circuit further includes an operation amplifier, a resistor and a capacitor arranged to integrate the output of the sensor winding and generate a high output signal to the feedback controlled circuit if the flow monitored or supervised electromagnetic is above a minimum threshold value or low output signal if the monitored or supervised electromagnetic flow is below the minimum threshold value. 40. A circuit breaker arrangement, according to claim 29, wherein the solenoid feedback circuit includes a circuit arranged and constructed to monitor a rate of change in the electromagnetic flux in response to the current drawn from the power source for operate the circuit interruption mechanism during the high-level duration of the current pulse of the timing circuit. 41. A circuit breaker arrangement, according to claim 40, wherein the solenoid feedback circuit includes a coil of sensor coils wound around a solenoid plunger of the circuit breaker mechanism to detect the changing electromagnetic flux in the solenoid , the output of the sensor winding being directly proportional to the voltage signal of the power source immediately after the start of the high-level pulse of the timing circuit. 42. A circuit breaker arrangement, according to claim 41, wherein the solenoid feedback circuit further includes an operation amplifier and a pair of resistors to establish an amplification factor, the solenoid feedback circuit being arranged to generate a high output signal to the feedback controlled circuit if the monitored or supervised electromagnetic flow is above a minimum threshold value or a low output signal if the monitored or supervised electromagnetic flow is below the minimum threshold value. 43. A circuit breaker arrangement, according to claim 29, wherein the solenoid feedback circuit includes a circuit arranged and constructed to monitor a signal proportional to a current flowing in the circuit path, where the supervised signal is a negative signal of the current-inducing circuit. 44. A circuit breaker arrangement, according to claim 43, wherein the solenoid feedback circuit further includes a blocking diode, a resistor-capacitor network filter, voltage divider resistors and a comparator for comparing the supervised signal or monitored with a reference voltage developed between the voltage divider resistors. 45. A circuit breaker arrangement, according to claim 44, wherein the comparator generates a high output signal to the feedback controlled circuit when the monitored signal falls to a negligible level and low output signal when the monitored or supervised signal is greater than the reference voltage. 46. A circuit breaker arrangement, according to claim 29, wherein a successful attempted trip of the circuit interrupting mechanism is detected by the solenoid feedback circuit during the high-level duration of the timing pulse of the timing circuit, and wherein the solenoid feedback circuit generates a high output signal received by the feedback controlled circuit that continues the electrical signal of the trip command circuit during the low level duration of the current pulse of the timing circuit, thereby completing the shot. 47. A circuit breaker arrangement, according to claim 29, wherein an attempted failed trip of the circuit breaker mechanism is detected by the solenoid feedback circuit during the high-level duration of the current pulse of the timing circuit and where the solenoid feedback circuit generates a low output signal received by the feedback controlled circuit that discontinues the electrical signal of the trip command circuit during the low level duration of the timing pulse of the timing circuit, thereby aborting the shot. 48. A circuit breaker arrangement for interrupting current in a circuit path, comprising: a power source circuit that extracts operating energy directly from the circuit path via an input terminal or an output terminal of the switch arrangement and providing a voltage signal relative to the common; a current-inducing circuit for providing a current signal having a magnitude corresponding to the current in the circuit path; a fault detection circuit, which responds to the current-inducing circuit, to detect a fault in the circuit path and to send an electrical signal that orders the circuit path to be interrupted using the voltage signal provided by the source circuit of energy; and a trip mechanism constructed and arranged to interrupt the current in the circuit path in response to the electrical signal. 49. A circuit breaker arrangement, according to claim 48, wherein the power source includes a three-phase rectifier. 50. A circuit breaker arrangement, according to claim 49, wherein the power source further includes a capacitor arranged to be charged to a supply voltage via the current provided by the circuit path. 51. A circuit breaker arrangement, according to claim 50, further comprising a current shielding circuit connected to the capacitor and shielding the current exceeding a predetermined threshold. 52. A circuit breaker arrangement, according to claim 51, further comprising an indicator operating from the power source circuit and indicating the presence of energy. 53. A circuit breaker arrangement, according to claim 52, wherein the indicator includes an LED. 5 . A circuit breaker arrangement for interrupting the current in a circuit path, where the current in the circuit path is provided using a control circuit that operates a coil of contact device, the switch arrangement comprising: a power source circuit which extracts operating energy from the control circuit that operates the coil of the contact device and providing a voltage signal relative to the common; a fault detection circuit, responding to a fault in the circuit path, for sending an electrical signal that commands the circuit path to be interrupted using the voltage signal provided by the power source circuit; and a trip mechanism constructed and arranged to interrupt the current in the circuit path in response to the electrical signal. 55. A circuit breaker arrangement, according to claim 54, wherein the power source circuit includes a pair of Zener diodes arranged in series with the coil of the contact device. 56. A circuit breaker arrangement, according to claim 55, wherein the Zener diodes are arranged and constructed to avoid applying a voltage to the coil of the contact device with a direct current shift. 57. A circuit breaker arrangement, according to claim 54, wherein the power source circuit includes a capacitor arranged to be charged to a supply voltage via the current provided by the control circuit. 58. A circuit breaker arrangement, according to claim 54, further comprising an indicator operating from the power source circuit and indicating the presence of energy. 59. A circuit breaker arrangement, according to claim 58, wherein the indicator includes an LED. 60. A circuit breaker arrangement, according to claim 54, wherein the power source includes an amplification regulator. A self-energized circuit breaker arrangement to interrupt current in a circuit path uses a current-blocking component to ensure that an insufficient amount of accumulated energy to drive the circuit path interruption is not wasted in an unwarranted attempt to interrupt the current path. The array includes a current-inducing circuit to provide a current signal having a magnitude corresponding to the current in the circuit path; an energy source operating from the current signal provided by the current inductor and providing a voltage signal of a predetermined value relative to the common; a solenoid mechanism having a coil through which current passes from the power source to cause interruption of the current in the circuit path; a trigger command circuit, responding to a fault in the circuit path and including an overload detector, for sending an electrical signal that commands the circuit path to be interrupted; an electric bolt driven in response to both the electrical signal from the trip command circuit and the voltage signal exceeding a predetermined value, the electric bolt arranged in series with the coil between the power source and the common and including a first terminal coupled to the trigger command circuit and a second terminal coupled to the power source; and a prevention circuit constructed and arranged to prevent an electrical signal from the firing command circuit or voltage signal from linking the electric bolt until the voltage signal exceeds the predetermined value. Various alternative arrangements are also described to overcome the problems of self-energizing a circuit breaker.