JP2016025457A - Switching arrangement - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a switching arrangement capable of reducing standby power.SOLUTION: A contact point 101 of a relay 10 is located in an electrical circuit which connects an AC power source 200 and an illumination load 300 thereacross. A contact point 111 of a relay 11 is located in an electrical circuit which connects an AC power source 200 and a ventilator load 400 thereacross. A first drive circuit 20 switches the state of the contact point of the contact points 101 and 111 to either one of a first state and a second state being supplied an electric power necessary for driving the relays 10 and 11 from the AC power source 200. In the first state, the switching circuit 30 allows a current from the AC power source 200 to the first drive circuit 20 via a first current path RT1. In the second state, the switching circuit 30 shuts off the first current path RT1 and switches the channel of the current to allow the current to flow from the AC power source 200 to a second current path RT2 which has an impedance higher than that of the first current path RT1.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a switch device, and more particularly to a switch device for switching between a state in which power is supplied from an AC power source to a load and a state in which the supply of power is cut off.

  2. Description of the Related Art Conventionally, there has been proposed an automatic switch with a heat ray sensor that includes a heat ray sensor that detects a heat ray emitted from a human body, and that switches a ventilation fan load to an on state or an off state based on the output of the heat ray sensor (for example, Patent Documents). 1).

  The automatic switch with a heat ray sensor described in Patent Document 1 includes a latching type relay in which a contact is inserted between a commercial power source and a ventilation fan load, and a signal processing unit. When the heat ray sensor detects a heat ray in a state where the contact is off, the signal processing unit applies a current to the set coil of the relay to switch the contact to the on state, thereby operating the ventilation fan load.

  In this automatic switch with a heat ray sensor, the commercial power supply is rectified by a rectifier, and the output of the rectifier is stabilized by a power supply circuit unit to supply an operating voltage to the signal processing unit. A parallel circuit of a Zener diode and an electrolytic capacitor is connected between the output terminals of the rectifier via a diode. The output voltage of the rectifier is clamped to a Zener voltage by a Zener diode and smoothed by an electrolytic capacitor. An exciting current is supplied to the set coil or the reset coil by the voltage across the electrolytic capacitor.

JP 2005-183319 A

  In the automatic switch with a hot-wire sensor described in Patent Document 1, when the output voltage of the rectifier exceeds the Zener voltage even when the relay is off, the Zener diode is turned on and current flows through the Zener diode. At this time, since a current having the same magnitude as the current flowing through the set coil or the reset coil flows through the Zener diode, there is a problem that power is wasted in a state where the ventilation fan load is stopped.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a switch device with reduced standby power.

  The switch device according to the present invention includes a switch element that is electrically connected in the middle of an electric circuit that connects an AC power supply and a load, and obtains electric power required to drive the switch element from the AC power supply. A drive circuit that selectively switches the contact state of the element to one of a first state and a second state; and in the first state, a current is passed from the AC power source to the drive circuit via a first current path, In the second state, a switching circuit that cuts off the first current path and switches a current flowing path so that a current flows from the AC power source to a second current path having a higher impedance than the first current path. And.

  ADVANTAGE OF THE INVENTION According to this invention, the switch apparatus which reduced standby power can be provided.

It is a circuit diagram of an embodiment.

  Hereinafter, the switch device according to the present embodiment will be described with reference to the drawings. However, the configuration described below is merely an example of the present invention. The present invention is not limited to the following embodiments, and various modifications can be made according to the design and the like as long as they do not depart from the technical idea of the present invention.

  FIG. 1 is a circuit diagram of the switch device 1 of the present embodiment.

  The switch device 1 according to this embodiment includes relays 10 and 11 (switch elements), a first drive circuit 20 (drive circuit), and a switching circuit 30. In addition to the above configuration, the switch device 1 of the present embodiment includes a bidirectional thyristor 12, a signal processing unit 40, a second drive circuit 50, a surge absorber circuit 60, a human sensor 70, and a power supply circuit. 80.

  The switch device 1 includes two input terminals 91 and 92 to which an AC power source 200 such as a commercial AC power source is connected, two load terminals 93 and 94 to which a lighting load 300 is connected, and a ventilation fan load 400. Two load terminals 95 and 96 to be connected are provided. The input terminal 92 and the load terminals 93 and 95 are electrically connected via the internal wiring of the switch device 1. The illumination load 300 is an LED lighting apparatus that uses, for example, a light emitting diode (LED) as a light source.

  Between the input terminal 91 and the load terminal 94, the contact 101 of the electromagnetic relay 10 which is a switch element is connected. A current limiting resistor R <b> 1 is connected between the load terminal 93 and the load terminal 94. In a state where the AC power source 200 is connected between the input terminals 91 and 92 and the lighting load 300 is connected between the load terminals 93 and 94, a parallel circuit of the resistor R1 and the lighting load 300 is connected between both ends of the contact 101. The AC power source 200 is connected via

  A series circuit of the bidirectional thyristor 12 and the coil L1 is connected between both ends of the contact 101. A bidirectional thyristor 512 on the output side of the photocoupler 51 is electrically connected between the T2 terminal and the gate terminal of the bidirectional thyristor 12 via a resistor R2. A parallel circuit of a resistor R3 and a capacitor C1 is connected between the gate terminal of the bidirectional thyristor 12 and the T1 terminal.

  Between the input terminal 91 and the load terminal 96, the contact 111 of the electromagnetic relay 11 which is a switch element is connected. In a state where the AC power source 200 is connected between the input terminals 91 and 92 and the ventilation fan load 400 is connected between the load terminals 95 and 96, the series circuit of the AC power source 200 and the ventilation fan load 400 is electrically connected between both ends of the contact 111. Connected.

  A rectifier DB1 formed of a diode bridge is connected between the input terminal 91 and the input terminal 92 through a series circuit of a resistor R5 and a capacitor C3.

  A switching circuit 30 is connected to the output side of the rectifier DB1. The switching circuit 30 includes a resistor R6, Zener diodes ZD1 and ZD2, and a transistor 31.

  Here, a series circuit of a resistor R6 and a Zener diode ZD1 is connected between the DC output terminals of the rectifier DB1. The cathode of the Zener diode ZD1 is connected to the resistor R6, and the anode of the Zener diode ZD1 is connected to the low potential side DC output terminal (circuit ground) of the rectifier DB1.

  The transistor 31 is an NPN type transistor. The collector of the transistor 31 is connected to the DC output terminal on the high potential side of the rectifier DB1 through the Zener diode ZD2. Here, the cathode of the Zener diode ZD2 is connected to the DC output terminal on the high potential side of the rectifier DB1, and the anode of the Zener diode ZD2 is connected to the collector of the transistor 31. The base of the transistor 31 is connected to a connection point between the resistor R6 and the Zener diode ZD1.

  A smoothing capacitor C4 made of, for example, an electrolytic capacitor is connected between the emitter of the transistor 31 and the circuit ground. The emitter of the transistor 31 is electrically connected to the anode of an LED (Light Emitting Diode) 511 included in the photocoupler 51 via a resistor R7. The cathode of the LED 511 is connected to the circuit ground via a switch element 52 (for example, a transistor). The control terminal of the switch element 52 is connected to the output port P3 of the signal processing unit 40, and the switch element 52 is switched on and off according to the voltage level of the output port P3.

  One end of a relay coil 102 provided in the relay 10 is electrically connected to the emitter of the transistor 31. The other end of the relay coil 102 is connected to the circuit ground via a series circuit of a resistor R10 and a switch element 21 (for example, a transistor). A diode D1 is connected to the relay coil 102 in parallel. The cathode of the diode D1 is connected to the emitter of the transistor 31, and the anode of the diode D1 is connected to the resistor R10. The diode D <b> 1 is provided to form a path through which current flows due to the counter electromotive force generated in the relay coil 102 when the current flowing through the relay coil 102 is interrupted. The control terminal of the switch element 21 is connected to the output port P1 of the signal processing unit 40, and the switch element 21 is switched on and off according to the voltage level of the output port P1.

  In addition, one end of a relay coil 112 provided in the relay 11 is electrically connected to the emitter of the transistor 31. The other end of the relay coil 112 is connected to the circuit ground through a series circuit of a resistor R11 and a switch element 22 (for example, a transistor). A diode D2 is connected to the relay coil 112 in parallel. The cathode of the diode D2 is connected to the emitter of the transistor 31, and the anode of the diode D2 is connected to the resistor R11. The diode D <b> 2 is provided to form a path through which current flows due to the counter electromotive force generated in the relay coil 112 when the current flowing through the relay coil 112 is interrupted. The control terminal of the switch element 22 is connected to the output port P2 of the signal processing unit 40, and the switch element 22 is switched on and off according to the voltage level of the output port P2.

  Here, the contact state of the relays 10 and 11 which are switch elements from the current-limiting resistors R10 and R11 and the switch elements 21 and 22 is the first state (ON state) and the second state (OFF state). A first drive circuit 20 that selectively switches to any one is configured.

  The signal processing unit 40 is, for example, a microcomputer, and realizes a desired function when the microcomputer executes a program stored in a memory (not shown).

  The surge absorber circuit 60 includes a series circuit (RC series circuit) of a resistor R4 and a capacitor C2. The surge absorber circuit 60 is connected in parallel with the bidirectional thyristor 12 between the AC power supply 200 and the illumination load 300.

  The human sensor 70 includes a pyroelectric infrared detection element that detects, for example, heat rays (infrared rays) emitted from the human body. The human sensor 70 detects the presence or absence of a person in the detection area based on the detection result of the infrared detection element, and outputs a detection signal to the signal processing unit 40 when it is detected that a person is present.

  The power supply circuit 80 steps down the AC voltage input from the AC power supply 200, converts it to a DC voltage having a desired voltage value, and supplies an operating voltage to an internal circuit such as the signal processing unit 40.

  The switch device 1 of the present embodiment has the above-described configuration, and the operation of the switch device 1 will be described below.

  First, the operation of the switch device 1 when no person is present in the detection area of the human sensor 70 will be described.

  When there is no person in the detection area of the human sensor 70, no detection signal is input from the human sensor 70 to the signal processing unit 40, and the signal processing unit 40 turns off the illumination load 300 and the ventilation fan load. In order to stop 400, the following operation is performed.

  In a state where no detection signal is input from the human sensor 70, the signal processing unit 40 sets all the voltage levels of the output ports P1, P2, and P3 to a low level and turns off all the switch elements 21, 22, and 52. . In this case, no current flows through the relay coils 102 and 112, and both the contacts 101 and 111 are turned off. In addition, since no current flows through the LED 511 and the bidirectional thyristor 512 is turned off, the bidirectional thyristor 12 is turned off. Therefore, when there is no person in the detection area of the human sensor 70, the illumination load 300 is turned off and the ventilation fan load 400 is stopped. When all the switch elements 21, 22, and 52 are turned off, the base current does not flow through the transistor 31, and the transistor 31 is turned off. Therefore, during the period when the output voltage of the rectifier DB1 exceeds the Zener voltage of the Zener diode ZD1, a current flows from the rectifier DB1 through the resistor R6 and the Zener diode ZD1. Here, the resistor R6 and the Zener diode ZD1 form a second current path RT2 through which a current flows from the AC power source 200 in the second state (a state in which no excitation current flows through the relay coils 102 and 112). A resistor R6 for limiting the current flowing through the second current path RT2 is connected to the second current path RT2.

  Next, the operation of the switch device 1 when a person is present in the detection area of the human sensor 70 will be described.

  When a person is present in the detection area of the human sensor 70 and a detection signal is input from the human sensor 70 to the signal processing unit 40, the signal processing unit 40 turns on the lighting load 300 and causes the ventilation fan load 400 to perform a ventilation operation. The following operations are performed to perform

  First, the signal processing unit 40 switches the voltage levels of the output ports P2 and P3 from the low level to the high level while keeping the voltage level of the output port P1 at the low level. At this time, the switch element 21 continues to be in the off state, and the switch elements 22 and 52 are switched from the off state to the on state.

  When the switch element 22 is turned on, a base current flows through the transistor 31, the transistor 31 is switched from the off state to the on state, and the capacitor C4 smoothes the pulsating voltage input from the rectifier DB1. At this time, when a current flows from the capacitor C4 through the path of the relay coil 112 → the resistor R11 → the switch element 22, an exciting current flows through the relay coil 112, and the contact 111 of the relay 11 is turned on. When the contact 111 is turned on, AC power is supplied from the AC power source 200 to the ventilation fan load 400 via the contact 111, and the ventilation fan load 400 rotates a motor (not shown) to perform a ventilation operation.

  When the switch element 52 is turned on, a current flows from the capacitor C4 through the resistor R7 → the LED 511 → the switch element 52, and the bidirectional thyristor 512 is turned off at the zero cross point of the AC voltage input from the AC power supply 200. Switches from on to on. When the bidirectional thyristor 512 is turned on, a voltage exceeding the breakover voltage is applied to the gate electrode of the bidirectional thyristor 12, and the bidirectional thyristor 12 is switched from the off state to the on state. When the bidirectional thyristor 12 is turned on, AC power is supplied from the AC power source 200 to the illumination load 300 via the bidirectional thyristor 12, and the illumination load 300 is turned on.

  Here, since the illumination load 300 is a resistance load, when the bidirectional thyristor 12 is turned on, an inrush current flows from the AC power supply 200 to the illumination load 300. When the lighting load 300 is lit, an inrush current flows through the bidirectional thyristor 12 that is a semiconductor switch, not the contact 101 of the relay 10, so that the contact 101 can be protected. Note that the ventilation fan load 400 is an inductive load, and no inrush current flows into the ventilation fan load 400 when the contact 111 is turned on. Therefore, a bidirectional thyristor is not connected in parallel to the contact 111, and the ventilation fan load 400 is only connected to the contact 111. The power to is turned on / off.

  The signal processing unit 40 switches the voltage level of the output port P1 from the low level to the high level when a preset first delay time elapses from the time when the bidirectional thyristor 12 is switched from the off state to the on state. At this time, the switch element 21 is switched from the OFF state to the ON state, and the exciting current flows through the relay coil 102, so that the contact 101 is turned ON. The signal processing unit 40 switches the voltage level of the output port P3 from the high level to the low level when a preset second delay time elapses from the time when the contact 101 is switched from the off state to the on state. At this time, the switch element 52 is switched from the on state to the off state, and current does not flow to the LED 511, so that the bidirectional thyristor 512 is turned off. When the bi-directional thyristor 512 is turned off, the bi-directional thyristor 12 is turned off, and a current flows from the AC power source 200 to the lighting load 300 only through the contact 101. The first delay time only needs to be set to a time slightly longer than the time during which the inrush current flows when the lighting load 300 is turned on, and is about 1 second, for example. The second delay time only needs to be set to a time slightly longer than the operation time required from when the relay coil 102 is energized until the contact 101 is closed. It only has to be set to time.

  In this way, when the human sensor 70 detects a person, the switch device 1 turns on the illumination load 300 and causes the ventilation fan load 400 to perform a ventilation operation. In the switch device 1, the lighting load 300 is turned on by switching the bidirectional thyristor 12 from the off state to the on state, so that the contact 101 is less likely to be welded due to the inrush current that flows at the beginning of lighting. In addition, after the first delay time and the second delay time have elapsed since the lighting load 300 is turned on, the switch device 1 supplies a current to the lighting load 300 via the contact 101, and thus bidirectional by energization. Heat generation of the thyristor 12 and power loss in the bidirectional thyristor 12 can be reduced.

  Further, in the first state in which the exciting current flows through the relay coils 102 and 112, the exciting current flows from the rectifier DB1 to the relay coils 102 and 112 via the Zener diode ZD2 and the transistor 31. In this embodiment, since the capacitor C4 is connected between the emitter of the transistor 31 and the circuit ground, the voltage input from the rectifier DB1 via the Zener diode ZD2 and the transistor 31 is almost equal to the capacitor C4. Smoothed to a constant voltage. Since the voltage smoothed by the capacitor C4 is applied to the relay coils 102 and 112, a stable current can flow through the relay coils 102 and 112. Here, the Zener diode ZD2 and the transistor 31 constitute a first current path RT1 through which a current flows from the AC power supply 200 to the first drive circuit 20. Compared with the first current path RT1, the second current path RT2 includes the resistor R6, so that the impedance of the second current path RT2 is higher than the impedance of the first current path RT1. Therefore, compared to the first state in which the exciting current is supplied to the relay coils 102 and 112, in the second state in which the exciting current is not supplied to the relay coils 102 and 112, the current flowing from the AC power supply 200 to the switching circuit 30 is suppressed. Electric power can be reduced.

  Next, the operation of the switch device 1 when no one is present from the detection area of the human sensor 70 in a state where the illumination load 300 is lit and the ventilation fan load 400 is performing a ventilation operation will be described.

  When no person is present in the detection area of the human sensor 70, no detection signal is input from the human sensor 70 to the signal processing unit 40. The signal processing unit 40 performs the following operation to turn off the illumination load 300 and stop the ventilation fan load 400 when a preset operation holding time has elapsed after the detection signal is no longer input.

  The signal processing unit 40 switches the voltage level of the output ports P <b> 1 and P <b> 2 from the high level to the low level when the operation holding time has elapsed since the detection signal is no longer input from the human sensor 70. Further, the signal processing unit 40 keeps the voltage level of the output port P3 at a low level. In this case, current stops flowing through the relay coils 102 and 112, the contacts 101 and 111 are switched from the on state to the off state, the lighting load 300 is turned off, and the ventilation fan load 400 stops the ventilation operation.

  Here, since the ventilation fan load 400 is an inductive load, when the ventilation fan load 400 stops the ventilation operation, a counter electromotive force about several times the rated voltage is generated.

  When the switch device 1 does not include the surge absorber circuit 60 and the electric wire connected to the load terminal 94 and the electric wire connected to the load terminal 95 are close to each other, and there is a stray capacity between the electric wires, the ventilation fan load 400 There is a possibility that the counter electromotive force generated in the circuit wraps around the photocoupler 51. When the counter electromotive force generated in the ventilation fan load 400 goes around the photocoupler 51 and a voltage exceeding the breakover voltage is applied to the bidirectional thyristor 512, the bidirectional thyristor 512 and the bidirectional thyristor 12 are turned on for a short time. Since the illumination load 300 uses an LED having better response than an incandescent lamp as a light source, the illumination load 300 can be turned on instantaneously when the bidirectional thyristor 512 and the bidirectional thyristor 12 are turned on for a short time. There is sex.

  In the switch device 1 of the present embodiment, a surge absorber circuit 60 composed of a series circuit of a resistor R4 and a capacitor C2 is connected in parallel with the bidirectional thyristor 12. That is, the surge absorber circuit 60 is connected in parallel with a series circuit of the resistor R2, the bidirectional thyristor 512, and the resistor R3. Therefore, even if a counter electromotive force is generated in the ventilation fan load 400 when the contact 111 is turned off, the capacitor C2 is charged through the resistor R4, so that the voltage rises slowly and is applied to the bidirectional thyristor 512. The surge voltage is reduced. Therefore, the counter electromotive force generated in the ventilation fan load 400 makes it difficult for the bi-directional thyristor 512 to break over, and the lighting load 300 is less likely to light up momentarily. The surge absorber circuit 60 is not limited to the RC series circuit of the resistor R4 and the capacitor C4, and may have other circuit configurations or a varistor (not shown).

  The signal processing unit 40 stops the load (the lighting load 300 and the ventilation fan load 400) after the operation holding time has elapsed since the human sensor 70 no longer detects a person. It may be set or may be adjustable. For example, the switch device 1 may include a setting switch (not shown) such as a dip switch or a rotary switch, and the operation holding time may be set to a desired time by the setting switch. Further, when the detection signal is not input from the human sensor 70 (that is, when the human sensor 70 no longer detects a person), the signal processing unit 40 immediately turns off the illumination load 300 and sets the ventilation fan load 400 to It may be stopped.

  As described above, the switch device 1 according to this embodiment includes the relays 10 and 11 (switch elements), the first drive circuit 20 (drive circuit), and the switching circuit 30. The contact 101 of the relay 10 is electrically connected in the middle of an electric circuit connecting the AC power source 200 and the illumination load 300 (load). The contact 111 of the relay 11 is electrically connected in the middle of an electric circuit connecting the AC power source 200 and the ventilation fan load 400 (load). The first drive circuit 20 obtains electric power necessary to drive the relays 10 and 11 from the AC power source 200 and selectively selects the contact state of the relays 10 and 11 as one of the first state and the second state. Switch to. The switching circuit 30 causes a current to flow from the AC power supply 200 to the first driving circuit 20 via the first current path RT1 in the first state. The switching circuit 30 cuts off the first current path RT1 in the second state, and allows the current flow path to flow from the AC power supply 200 to the second current path RT2 having a higher impedance than the first current path RT1. Switch.

  Thus, the second current path RT2 through which current flows from the AC power supply 200 in the second state has a higher impedance than the first current path RT1. Therefore, the input current from the AC power supply 200 is smaller in the second state in which no current is passed through the first drive circuit 20 than in the first state in which current is passed through the first drive circuit 20. It is possible to reduce power consumption in a standby state where the relays 10 and 11 are not driven.

  Moreover, in the switch apparatus 1 of this embodiment, you may provide the two relays 10 and 11. FIG. The number of relays that are switch elements is not limited to two, but may be three or more, and can be changed as appropriate. In the case where a plurality of switch elements are provided, the power consumed by the first drive circuit 20 that drives the switch elements is increased compared to the case where one switch element is provided, but the power consumption reduction effect in the standby state is also improved. growing.

  Further, the switch device 1 of the present embodiment may further include the following configuration. The switch elements are relays 10 and 11. The switching circuit 30 includes a transistor 31, a resistor R6, and a Zener diode ZD1. The transistor 31 has a collector-emitter connected in the middle of the first current path RT1. Resistor R6 is connected between the collector and base of transistor 31. The Zener diode ZD1 is connected between the base and the circuit ground with the anode as the base side. The relay coils 102 and 112 of the relays 10 and 11 are connected to the emitter of the transistor 31. The first current path RT1 includes a transistor 31, and the second current path RT2 includes a series circuit of a resistor R6 and a Zener diode ZD1.

  Here, in the first state, an exciting current flows through the relay coils 102 and 112 of the relays 10 and 11 through the transistor 31, and in the second state, the AC power supply 200 is connected to the circuit ground through the resistor R6 and the Zener diode ZD1. Current flows. Therefore, since the current flowing through the second current path RT2 is limited by the resistor R6, the input current from the AC power supply 200 is smaller in the second state than in the first state, and the first drive circuit 20 is connected to the relay 10. , 11 can be reduced in power consumption in the standby state.

  By the way, in the switch device 1 of the above-described embodiment, the relays 10 and 11 are non-latching relays, but may be latching relays. When the relays 10 and 11 are latch-type relays, each of the relays 10 and 11 includes a set coil and a reset coil. When a current flows through the set coil, the contact is turned on, and the contact remains on even when the energization to the set coil is stopped. When a current flows through the reset coil, the contact is turned off, and the contact remains off even when the energization to the reset coil is stopped.

  In the switch device 1 of the present embodiment, the illumination load 300 and the ventilation fan load 400 are connected as loads. However, the load of the switch device 1 is not limited to the illumination load 300 and the ventilation fan load 400, and other electrical devices. May be connected.

  In the switch device 1 of the present embodiment, the operation of the load is controlled by using the detection signal input from the human sensor 70 as a trigger. However, the trigger that changes the operating state of the load is used by the human sensor 70. It is not limited to detection. For example, the switch device 1 changes the operating state of the load triggered by the operation of an operation unit (not shown) by a person or the reception unit (not shown) receiving a radio signal transmitted from a remote control transmitter. You may let them.

1 Switch device 10, 11 Relay (switch element)
20 First drive circuit (drive circuit)
30 switching circuit 31 transistor 101, 111 contact 102, 112 relay coil 200 AC power supply 300 lighting load (load)
400 Ventilation fan load (load)
R6 Resistor ZD1 Zener diode RT1 First current path RT2 Second current path

Claims (3)

A switch element electrically connected in the middle of the electrical path connecting the AC power supply and the load;
A drive circuit that obtains electric power necessary to drive the switch element from the AC power source and selectively switches the contact state of the switch element to either the first state or the second state;
In the first state, a current flows from the AC power source to the drive circuit through a first current path, and in the second state, the first current path is interrupted, and the impedance is higher than that of the first current path. A switching circuit for switching a current flow path so that a current flows from the AC power source to the second current path of
A switch device comprising:   The switch device according to claim 1, comprising a plurality of the switch elements. The switch element is a relay;
The switching circuit includes a transistor connected between a collector and an emitter in the middle of the first current path, a resistor connected between the collector and base of the transistor, and an anode on the base side. A Zener diode connected between the base and the circuit ground, the relay coil of the relay is connected to the emitter,
The switch device according to claim 1, wherein the second current path includes a series circuit of the resistor and the Zener diode.

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