JPH0250698B2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field] The present invention is a remote control breaker that can be manually operated on-site, and is configured to open and close contacts by remote control using an external voltage and manual operation on-site. The present invention relates to a control circuit for a manually operated remote switch for remotely controlling the manually operated remote switch.

[Background technology]

In general, this type of manually operated remote switch includes a remote control type circuit breaker and disconnector, such as the one disclosed in Japanese Patent Application Laid-Open No. 131636/1983, but such a switch is bistable depending on the direction of the input current. It is constructed so that the contacts can be opened and closed by both a bistable electromagnetic device that changes position and a handle device for manual operation. Therefore, when attempting to operate such a bidirectional electromagnet device using an external input voltage, the external voltage must be such that current of opposite polarity alternately flows through the bidirectional electromagnet device, and therefore, the The control circuit is of a completely different type from the control circuit of a general electromagnetic relay, which operates when a voltage is applied and does not operate when no voltage is applied, and has the problem of poor usability.

In order to solve this problem, a circuit as shown in FIG. 1 has been conventionally provided. In the conventional circuit shown in FIG. 1, a capacitor C is connected in series with the coil L of a bistable electromagnet device, and an input voltage V _IN is applied to this series circuit, and the discharge of the capacitor C is controlled by a transistor Tr. is configured to do so. Now, when input voltage V _IN as shown in Figure 2 a is applied, a charging current of capacitor C flows through diode D and coil L when the input voltage V _IN rises, as shown in Figure 2 b. A downward set-side coil current in FIG. 1 flows through the coil L, causing the bidirectional electromagnet device to perform a set operation. Next, when the input voltage V _IN falls, the base bias of the transistor Tr is applied via the resistor R1 by the charge of the capacitor C, which turns on the transistor Tr, and the discharge current of the capacitor C is transferred to the transistor Tr. The current flows from the collector/emitter of the current through the coil L, and as shown in FIG. 2b, the reset side coil current flowing upward in FIG. 1 flows through the coil L as shown in FIG. 2b. However, the conventional example shown in FIG. 1 has the problem that it can be driven only when the input voltage V _IN is direct current, and the rise and fall of the input voltage V _IN changes smoothly. In such a case, there was a problem that the bidirectional electromagnet device could not be driven appropriately in response to such an input.

Therefore, in the conventional example shown in Fig. 3, the threshold value of the input voltage V _IN is detected by a bidirectional switching element S, so that it can operate properly even when the input voltage V _IN has smooth rises and falls. This is what I did.
That is, the conventional example circuit shown in FIG. 3 has a bidirectional switching element S connected in series to a capacitor C, and a resistor R2 connected in parallel to this bidirectional switching element S. Voltage V _IN
For the set side switching level L ₁ ,
At the reset side switching level _L2 , the bidirectional switching element S performs a switching operation, as shown in Fig. 4b.
The set-side and reset-side coil currents shown in FIG. In this way, in the conventional example shown in Figure 3, even when the input voltage V _IN changes smoothly, sufficient coil current can be obtained on the set side and reset side, and the bidirectional electromagnet device can operate properly. However, on the other hand, when the input voltage V _IN is set to AC (half-wave rectified current) as shown in Figure 5a, the capacitor is charged in the coil L every cycle as shown in Figure 5b. Discharge is repeated, and the coil L of the bidirectional electromagnet device responds to the current, so there is still an unresolved problem that it cannot be used with alternating current.

[Purpose of the invention]

The present invention can be driven by opening and closing AC input, and has the same usage functions as general electromagnetic relays, as well as being able to be operated manually so that it can be turned off reliably even when the relay is turned off immediately after being turned on. The purpose is to provide a control circuit for a remote switch.

[Disclosure of the invention]

FIG. 6 shows a circuit according to an embodiment of the present invention, in which a switching contact Ry of a (second) relay Ry1 is used as a switching means that is switched during an ON operation or an OFF operation.
1-1 is used, and when the operation switch SW is operated to connect the AC power supply to the circuit, the above-mentioned relay Ry1 is also activated and the NO side of the switching contact Ry1-1 is closed. There is.
In addition, D1 to D5 in FIG. 6 are diodes, and R1 to R
2 is a resistor, Ry2-1 is the output switching contact of the one shot circuit 3, L is a coil, C is a capacitor, MS
is the main contact, Ss is the auxiliary contact, and 1 is a circuit that functions as a remote switch that detects overcurrent or short-circuit current and performs a tripping operation, as well as remote control or manual off operation. 2 is a control circuit thereof, and 4 is a voltage detection switching circuit for detecting that the terminal voltage of capacitor C has reached a predetermined level, and this voltage detection switching circuit detects a predetermined level voltage. When this occurs, the NO side of the switching contact Ry2-1 is closed.

Now, in the circuit shown in Figure 6, when the operation switch SW is turned on, relay Ry1 operates and its switching contact
The NO side of Ry1-1 is closed, and capacitor C is charged via diode D ₄ , resistors R1 and R2, and diode D5. The voltage detection switching circuit 4 detects the voltage level of this capacitor C,
When this detection voltage level reaches a predetermined set level, a switching operation is performed to operate the one-shot circuit 3, and its output switching contact Ry2 is switched on for a predetermined period of time.
Close the NO side of -1. In this way, switching contact Ry2
By closing the NO side of -1, diode D
A downward set-side current in the figure flows through coil L of circuit breaker 1 through circuit breaker 1, main contact MS closes, auxiliary contact Ss reverses, and diode D2
Can be switched to the side. After this, the set time of the one-shot circuit 3 has elapsed, and the NC of the switching contact Ry2-1 has passed.
The sides are closed.

Next, in the above state, when the operation switch SW is turned off, the relay Ry1 returns to its normal state, the NC side of its switching contact Ry1-1 closes, and the discharge current of the capacitor C flows from the NC side of the switching contact Ry1-1 to the diode. D2, the reset side current flows through the NC side of the switching contact Ry2-1 to the coil L of the circuit breaker 1, returns the circuit breaker 1, opens the main contact MS, and at the same time opens the auxiliary contact Ss. The diode D1
Flip to the side.

FIG. 7 shows a specific circuit example of the embodiment shown in FIG. 6, and parts having the same numbers and symbols as those in FIG. 6 are the same parts. Thus, in the specific circuit example shown in Figure 7,
By controlling the phase of SCR1, transistors Q1 and Q2 are made conductive up to a predetermined phase of the first half of each half-wave of the full-wave rectified power supply wave, and by controlling the charging of capacitor C2, a predetermined voltage is obtained across Zener diode ZD1. , when the operating switch SW is turned on, the relay Ry1 is driven with a predetermined voltage. In addition, a voltage detection switching circuit 4 is configured by resistors R10, R11 and a Zener diode ZD2, and by triggering SCR2 with this output, relay Ry2 is driven for a predetermined time determined by the time constant of capacitor C5 and resistor R13, and switching is performed. The switching operation of the contact Ry2-1 is made. Furthermore, when the operating switch SW is turned off, the contact Ry1-1 of the relay Ry1 returns, so the charge in the capacitor C5 is transferred to the diode D.
7. Resistor R1, diode D4, diode D
6. Discharged through resistor R14. Other operations are similar to the embodiment shown in FIG.

〔Effect of the invention〕

Since the present invention is configured as described above, it is possible to drive a bidirectional electromagnetic device (circuit breaker) that performs holding type operation like a remote control breaker simply by opening and closing the AC input. In addition to having the effect of greatly improving usability, current flows through the coil of a bidirectional electromagnetic device (circuit disconnector) only for a very short time when it is on and off, and it is not constantly excited. This has the effect of making manual opening/closing operations extremely easy.Moreover, it does not require a capacitor to be connected in series with the coil and the coil is excited by the excitation current when the coil is turned on, and the input voltage is directly applied. Since the voltage is applied to the coil, there is no possibility of inoperability due to the closing phase, and this has the effect of making it possible to reduce the capacitance of the capacitor and make it more compact. The voltage level of the capacitor that supplies the drive current is detected, and the switching contact for setting the remote switch is activated after this voltage reaches a predetermined level, making it impossible to turn off the switch immediately after turning it on. In this case, sufficient charge is stored in the capacitor to reset the remote switch without causing it to become inoperable.

[Brief explanation of the drawing]

Fig. 1 is a circuit diagram of the conventional example, Fig. 2 a and b are explanatory diagrams of the same operation as above, Fig. 3 is a circuit diagram of another conventional example, Fig. 4 is an explanatory diagram of the same as above, Fig. 5 a, b is an explanatory diagram of the operation when AC is applied as above, FIG. 6 is a block diagram of an embodiment of the present invention, FIG. 7 is a diagram of a specific circuit example of the same as above, and Ry1-2 are relays used as changeover switch means. Ry1 switching contact, C is capacitor,
Ry2-1 is a switching contact for one-shot circuit output,
Reference numeral 1 designates a circuit breaker provided as a remote switch, 3 a one-shot circuit, and 4 a voltage detection switching circuit.

Claims (1)

[Claims] 1. A changeover switch means that is switched between an ON operation and an OFF operation, a capacitor that is charged with an input voltage through the ON operation side contact of this changeover switch means, and a voltage detection switching circuit that detects the charging voltage of this capacitor; There is a one-shot circuit that operates when this voltage detection switching circuit detects that the terminal voltage of the capacitor reaches a predetermined voltage and switches the switching contact, and a remote switch that can be operated in reverse depending on the direction of input current. A current of one polarity is passed from the input power source to the remote switch through the ON operation side contact of the changeover switch means and the NO side changeover contact of the one shot circuit, and the OFF operation side contact of the changeover switch means. and a control circuit for a manual operation/remote switch, characterized in that the circuit is configured such that the discharge current of the capacitor is passed to the remote switch as a current of the other polarity through the NC side switching contact of the one-shot circuit.