JPH03293992A - Solid state contactor - Google Patents

Abstract

PURPOSE:To improve the property of safety by a method wherein a light emitting device is lighted only when a power is supplied to an input circuit, controlling the opening and closing of a switching element, and said switching element is energized under a condition that the power is supplied to a main circuit. CONSTITUTION:A solid state contactor is constituted of a signal contact (a), a trigger circuit, a contactor element S and the like. The solid state contactor is provided further with an operation indicating light emitting diode LED. A light emitting diode unit, which becomes the voltage detecting unit of a two-way photocoupler OI11, is connected between main circuits V-W between a switching element S and a load M while the switching unit is connected in series to the light emitting diode LED. When power is not supplied from a main circuit power supply, the light emitting diode LED is not lighted. When the power is supplied from the main circuit power supply and the contact (a) is turned ON, the contactor element S is turned ON and the light emitting diode LED is lighted.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention indicates the on/off state using the operating circuit voltage and the main circuit voltage. This invention relates to a solid state conductor operation display circuit.

[Prior art 1] Fig. 5 shows the configuration of a conventional solid-state conductor. , R3 is a resistance,
0, ~O1, is a photocoupler for driving the trigger circuit of each solid state conductor element, R+tRs is a resistor,
Contact a, light emitting diode LED. Resistor R2 and) odocoupler 01. ~O1, constitutes a signal input circuit.

Further, S is a solid state conductor element that is connected in series to each phase of the main circuit and is a switching element for opening and closing the main circuit, and M is a signal contact a that is a solid state conductor drive input signal contact when the load mode is not in use. When turned on, a current flows from the operating power supply through the resistors R, R2 to the operation display light emitting diode LED, lighting it up, and the photocoupler O1, .about.OIs for driving the trigger circuit of the solid state conductor element S also operates.

Since no power is supplied from the main circuit power supply, the solid state conductor element S is in an off state, and the load modele M is not supplied with voltage and is not excited. Next, when power is being supplied from the main circuit power supply, if signal contact a, which is the solid state conductor drive input signal contact, is turned on, current flows from the operation power supply through resistors R+ and R* to the operation display light emitting diode LED, which lights up. At the same time, the photocoupler OI, ~O1, for driving the trigger circuit of the solid-state conductor element S is also activated and the main circuit power is supplied, so the solid-state conductor element S is turned on and the mode for the load is activated. Voltage is supplied to M and it is excited. Note that there is a type of operation display circuit of this type that uses only the main circuit power supply as the power source for the display circuit (see Utility Model Application Publication No. 1-90239); Therefore, when a surge or noise enters the main circuit from the outside while no signal is being input to the input circuit, the LED may light up. However, the operation display circuit explained above uses LEDs.
Since the power is obtained from the operating power supply of the input circuit, the LED will not light up even if a surge or noise enters the main circuit from the outside when no signal is input to the input circuit.

[Problems to be Solved by the Invention] Conventional solid state conductor operation display circuits are configured as described above. There was a problem in displaying the operation of the state conductor.

The present invention has been made in order to solve the above-mentioned conventional problems, and the light emitting element is activated only when power is supplied to the input circuit and the switching element is conductive with power being supplied to the main circuit. An object of the present invention is to provide an operation display circuit for a solid-state contactor that can light up a solid state contactor.

[Means for Solving the Problems] A solid-state conductor according to the first invention is connected between any phase of a main circuit between a light-emitting element that receives power from an operating power source of an input circuit, a switching element, and a load. , a detection section that detects an open/closed state of the switching element, and a switching section that is provided on the input circuit side and controls lighting of the light emitting element based on a signal from the detection section, and the input circuit is powered from an operating power supply. and a detection circuit that makes the switching section conductive based on a signal from the detection section and lights up the light emitting element when the switching element is conductive. Further, the solid state conductor according to the second invention includes: a light emitting element that obtains power from an operating power source of the input circuit; a detection section connected in parallel to the switching element;
and a switching unit that is provided on the input circuit side and controls lighting of the light emitting element based on the signal from the detection unit, and the input circuit receives power from the operating power source and the switching element is conductive. and the above input circuit is receiving power from the operating power supply.

and a detection circuit that operates so that when power is being supplied to the main circuit from the main circuit power supply, the detection section detects this state and makes the switching section conductive based on a signal from the detection section to light up the light emitting element. a voltage detection section connected in parallel to the switching element to detect the voltage of the main circuit; and a voltage detection section provided on the input circuit side to control opening/closing of the switching section of the detection circuit based on a signal from the voltage detection section. a control section, when the input circuit receives power from the operating power supply and the main circuit is not supplied with power from the main circuit power supply, the control section controls the switching section according to a signal from the voltage detection section. The configuration includes a voltage detection circuit that prevents conduction.

[Effect]

According to these inventions, the light emitting element lights up only when power is being supplied to the input circuit and the switching element is conductive with power being supplied to the main circuit.

[Embodiment J of the Invention A first embodiment of the invention will be described below. 1st
In the figure, a is the drive input signal contact of the solid state conductor, LED is the light emitting diode for operation display, R8
is a resistor, OI + ~ O1, is a photocoupler for driving the trigger circuit of a solid state conductor element, R + and R - are resistors, and are input together with contact a, light emitting diode LED, resistor R2, and photocoupler (0, ~ O). It constitutes a circuit.

0 engineering 8. is a bidirectional photocoupler, in which a light emitting diode section serving as a voltage detection section is connected between V and W of the main circuit between the switching element S and the modele M, and the switching section is connected in series with the light emitting diode LED. ing. Rz is a current limiting resistor of the bidirectional photocoupler OI, ., and together with the bidirectional photocoupler OI, constitutes a load voltage detection circuit. Next, the operation will be explained using FIGS. 1 and 2. First, when power is not supplied from the main circuit power supply, if the solid state conductor drive input signal contact a is turned on, the solid state conductor element S is in the off state, and the bidirectional photocoupler O
No current flows through the light emitting diode 1, so the transistor of the bidirectional photocoupler O1 becomes non-conductive and the operation display light emitting diode LED does not light up. When the solid state conductor drive input signal contact a is turned on while power is being supplied from the 0th order main circuit power supply where voltage is not supplied to element M and it is not excited, the trigger circuit of the solid state conductor element S is activated by the operating power supply. The driving photocouplers OI to O1 are driven, the solid state conductor element S is turned on, and a current flows through the light emitting diode element of the bidirectional photocouplers OI. Therefore, the transistors of the bidirectional photocouplers OI, , become conductive, and the resistors R,, R,
A current flows through the light emitting diode LED for operation indication, and the LED lights up. At this time, solid state conductor element S
is in the on state, voltage is supplied to the load mode M, and it is in the excited state. Next, the second embodiment of this invention will be described in a third embodiment.
This will be explained using FIG. In FIG. 3, a is the drive input signal contact of the solid state conductor, L
ED is a light emitting diode for indicating operation, R2 is a resistor, and together with the light emitting diode LED, constitutes an indicator light circuit.

Or, ~01. is a photocoupler for driving the trigger circuit of solid state conductor element S, R, and R3 are of low resistance.
It constitutes an input circuit together with solid state conductors O1, to O2. 0IO1 and □ are bidirectional photocouplers in which one light-emitting guide portion is connected in series, and this series connection body is connected in parallel to the solid state conductor element S. R11 is a current limiting resistor, which together with the bidirectional photocoupler O1, transistor TR, and resistor R4 constitutes a detection circuit. Also, the bidirectional photocoupler O1, □, the transistor TR,.

The primary operation of the voltage detection circuit made up of the thyristor SCR and the resistors R, , R, , R will be explained. When no power is supplied from the main circuit power supply, if the solid-state conductor drive input signal contact a is turned on, the solid-state conductor element S is in the off state and the bidirectional photocoupler OI, .

No current flows through the light emitting diode of Oll, so the bidirectional photocoupler OI of the voltage detection circuit becomes non-conductive, so the thyristor SCR is not triggered and turns off, and the transistor TR, is turned on through the resistor R1. Therefore, the transistor T of the detection circuit
R, is locked in the OFF state, the light emitting diode LED for operation indication does not light up, and the moder M for load is not excited.

Next, power is supplied from the main circuit power supply, and when the solid-state conductor element S is in an off state, the transistors of the bidirectional photocoupler OI ++, OI + become conductive. If the solid state conductor drive input signal contact a turns on in this state, the operation power supply will
Photocouplers O11 to 01. for driving trigger circuits of solid state conductor elements S. operates, and the transistors of the bidirectional photocoupler O10, Oll remain conductive until the solid state conductor element S turns on, and the thyristor SCR of the one voltage detection circuit It is triggered through the transistor of the photocoupler OI, , and turns on. Cyrisk SC
When H is turned on, the transistor TR3 is turned off, and the transistor TR of the detection circuit is unlocked. When the solid-state conductor operates and the solid-state conductor element S is turned on, the transistor of the bidirectional photocoupler O11, Or, is turned off, but the transistor TR of the voltage detection circuit is turned off due to the self-holding effect of the Cyrisk SCR. In order to maintain the off state and also turn off the transistors of the bidirectional photocouplers OI, . When the signal No. 4 contact a is turned off, the solid state conductor is also turned off, but the self-holding of the thyristor SCR of the voltage detection circuit is also released, and the bidirectional photocoupler 01. , ,OI,2 are turned on to prepare for the next signal.

[Effect of the invention 1 As described above, according to the first and second inventions, when power is being supplied to the two-input circuit and the switching element is conducting with power being supplied to the main circuit, Since only the light-emitting element is turned on, the presence or absence of load voltage supply can be known by the light-emitting element being turned on or off, and electric shocks can be prevented, resulting in a highly safe product.

Further, according to the second invention, the open/close state detection of the switching element and the voltage detection section of the main circuit for lighting the light emitting element as described above are connected in parallel to the switching element without being connected between phases of the main circuit. Since it is connected to the main circuit, insulation between each phase of the main circuit is ensured, resulting in higher safety.

[Brief explanation of drawings]

FIG. 1 and FIG. 2 are diagrams related to an embodiment of the first invention,
FIG. 1 is a circuit diagram, FIG. 2 is a timing chart showing the operation, FIGS. 3 and 4 are diagrams related to an embodiment of the second invention, FIG. 3 is a circuit diagram, and FIG. 5 and 6 are diagrams related to a conventional example, FIG. 5 is a circuit diagram, and FIG. 6 is a timing chart diagram showing the operation. S is a solid-state conductor element, ■, ED is a light emitting diode, OI, ..., Ol, and □ are photocouplers. In addition, in the drawings, the same reference numerals indicate the same 2 or corresponding parts.

Claims (2)

[Claims] (1) A device that is connected in series to each phase of a main circuit consisting of multiple phases and is equipped with a switching element that opens and closes the main circuit, and an input circuit that obtains power from an operating power source and controls the opening and closing of the switching element. , connected between a light emitting element that receives power from the operating power source of the input circuit and any phase of the main circuit between the switching element and the load,
a detection unit that detects an open/closed state of the switching element; and a switching unit that is provided on the input circuit side and controls lighting of the light emitting element based on a signal from the detection unit;
and a detection circuit that makes the switching section conductive based on a signal from the detection section and lights up the light emitting element when the input circuit receives power from the operating power source and the switching element is conductive. solid state conductor. (2) A switching element connected in series to each phase of a main circuit consisting of multiple phases to open and close the main circuit, and an input circuit that obtains power from an operating power source and controls opening and closing of the switching element. A light emitting element that obtains power from the operating power source of the input circuit, a detection section connected in parallel to the switching element, and a light emitting element provided on the input circuit side, the light emitting element being turned on by a signal from the detection section. the input circuit is receiving power from the operating power source and the switching element is conducting, and when the input circuit is receiving power from the operating power source and the main circuit is a detection circuit that operates so that when power is not supplied from the main circuit power supply to the main circuit power supply, the detection section detects this state and makes the switching section conductive based on a signal from the detection section to light up the light emitting element; a voltage detection section connected in parallel to the switching element to detect the voltage of the main circuit; and a control section provided on the input circuit side to control opening/closing of the switching section of the detection circuit based on a signal from the voltage detection section. and when the input circuit is receiving power from the operating power source and the main circuit is not being supplied with power from the main circuit power source, the control section causes the switching section to turn on due to the signal from the voltage detection section. A solid state conductor comprising a blocking voltage detection circuit.