JPH0640752B2 - Distant monitoring equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to the operation and failure of a power load such as a general-purpose motor via a transmission / reception device connected to a load and an operation monitoring unit connected in series to the transmission / reception device. The present invention relates to a distant monitoring device for displaying a working state and monitoring a power load such as operation control thereof, and in particular, the monitoring can be stably performed with a simple structure by using a low AC voltage operating power supply and a single-line signal communication wiring. The present invention relates to a remote monitoring device that can give a priority to a control device for the load when there are a plurality of operation monitoring units.

[Prior Art] As such a conventional remote monitoring device, there is, for example, the one shown in FIG. This device includes a hand operation monitoring unit 2 for controlling a switching circuit 1 for a load such as a motor M and for displaying the operating state of load operation or failure, a remote operation monitoring unit 10 for sending a control command from a distance, and this control. It comprises a reception relay 9 for sending a command to the hand operation monitoring unit 2.

The motor M includes a circuit breaker MCB for short circuit protection, an electromagnetic contactor 52 for opening and closing a load, and a thermal relay 51 for overload protection.
Is connected to the three-phase power sources R, S, T via. The hand operation monitoring unit 2 includes a remote / hand changeover switch 6 and a hand O
FF push button switch normally closed contact 7, hand ON push button switch normally open contact 8, coil and auxiliary contact of electromagnetic contactor 52, contact of thermal relay 51, auxiliary relay of electromagnetic contactor and thermal relay, failure indicator lamp 3, operation display A lamp 4, a stop display lamp 5 and the like are provided. The reception relay 9 has a circuit including a distant OFF relay TX, a distant ON relay CX, a diode that detects a command voltage, and the like on a substrate.

[Problems to be Solved by the Invention] In the conventional device, by switching the selector switch 6 to the remote / hand side in the hand operation monitoring unit 2, the control of the motor M and the operation state of operation or failure are displayed from any of them. However, although the hand operation monitoring unit 2 is on the door side and the monitoring sequence circuit is relatively simple, a large number of wire connections must be made due to its structure. There was a problem that it did not happen.

In addition, many communication lines were required to connect the remote operation monitoring unit and the reception relay. Furthermore, the monitoring operation voltage is A
Generally, a high voltage of C200V is used, and since this high voltage is also supplied to the operation panel of the operation monitoring unit, there are many wire connections for the arrangement, control, and display of the operation panel. Together, they also had problems in terms of safety.

The present invention solves the problems of the conventional device, computerizes the sequence circuit for monitoring, simplifies the overall structure such as the wiring structure, and enables the use of a low-voltage AC power supply as the operation power supply. Excellent stability, reliability, and economic efficiency,
Further, it is an object of the present invention to provide a remote monitoring device in which a plurality of operation monitoring units can prioritize the load control operation.

[Means for Solving the Problems] The present invention employs the following means in order to achieve the above-mentioned object.

The configuration of the present invention is roughly divided into a transmission / reception device connected to a load and an operation monitoring unit connected in series to the operation power supply.

The transceiver device includes a control circuit and a pair of transceiver circuits. The control circuit detects a signal of the operating state of the operation of the load such as a motor or a failure through the voltage input circuit and sends the signal to the transmission / reception circuit, and based on the signal of the load operation control command input from the transmission / reception circuit. Operate the load. The pair of transmission / reception circuits send the operation state signal of the load sent from the control circuit to the operation monitoring unit, and also detect the signal of the operation control command of the load sent from the operation monitoring unit and send it to the control circuit. To do.

The pair of transmission / reception circuits respectively include a current input and output terminal, a signal input and output terminal, a current control transistor, a threshold current detection transistor, a threshold current setting resistor, a reception current limiting resistor, and a transmission and reception terminal. It has circuit elements of photocoupler.These circuit elements connect the collector of the current control transistor to the current input terminal and the collector of the light receiving transistor of the transmission photocoupler through the receiving current limiting resistor. The emitter of the light receiving transistor is connected to the base of the current control transistor and the collector of the threshold current detection transistor, and the emitter of the current control transistor is connected to the base of the threshold current detection transistor and the threshold current setting resistor. Threshold current detection by connecting to the current output terminal via The emitter of the transistor is connected to the end on the current output terminal side of the threshold current setting resistor via the light emitting diode of the receiving photocoupler, and the light emitting diode of the transmitting photocoupler is connected to the control circuit via the signal input terminal in the operating state. On the other hand, the light receiving transistor of the receiving photocoupler is connected to the control circuit via the output terminal of the control command signal.

A pair of transmission / reception circuits composed of a combination of such circuit elements has one common line and control line for the operating power supply.
In the meantime, they are connected in anti-parallel so that the current directions are opposite to each other via a pair of diodes connected in parallel with opposite polarities. That is, in one transceiver circuit, the current input terminal is connected to the cathode of one diode and connected to one end on the secondary side of the operation power supply via the common line, and the current output terminal is connected to the control line and the operation monitoring unit and the common line. Is connected to the other end of the secondary side of the operating power supply, and the other transmitting / receiving circuit has the current input terminal connected to the other end of the secondary side of the operating power supply via the control line, the operation monitoring unit and the common line. The current output terminal is connected to the anode of the other diode and connected to one end on the secondary side of the operating power supply via the common line.

On the other hand, the operation monitoring unit includes a common terminal and a master terminal located at both ends, a light emitting diode for displaying an operating state of a pair of loads connected in parallel with opposite polarities, a monitoring current limiting resistor and a control operation connected in parallel. It has a circuit element with a push button switch for use, and one end of the common terminal is connected to one end on the secondary side of the operating power supply via a common line and the other end is connected to a reverse parallel circuit of a pair of light emitting diodes. The other end of the anti-parallel circuit of the light emitting diode is connected to the parallel circuit of the monitoring current limiting resistor and the pushbutton switch for control operation, and the other end of the parallel circuit is connected to the master terminal. The other end of the terminal is connected to each of a current input terminal and an output terminal of the pair of transmission / reception circuits via a control line.

The above is the case where the operation monitoring unit is mainly single (of course, there may be a plurality of operation monitoring units having such a configuration, in which case, each operation monitoring unit is connected in parallel).

On the other hand, when there are a plurality of operation monitoring units, and when prioritizing the operation of the control command for the load of each operation monitoring unit, it is divided into the following two means.

In this case, the operation monitoring unit includes a first operation monitoring unit located near the transmitting / receiving device, and one or more second operation monitoring units located behind the first operation monitoring unit and connected in parallel to the operation power supply. It is equipped with.

First, in the first means, the first operation monitoring unit further includes, in addition to the circuit element of the operation monitoring unit configured as described above, a slave terminal and a changeover switch for switching between the slave terminal and the push button switch for control operation. It has an operating current limiting resistor, and the master terminal is connected to the parallel circuit of the control operation pushbutton switch and the series connection of the changeover switch when switching to this switch side and the monitoring current limiting resistor, while the slave terminal side It is also connected to the slave terminal through the parallel circuit of the changeover switch and the operation current limiting resistor at the time of switching to. The second operation monitoring unit connected in parallel to the first operation monitoring unit has the same configuration as the operation monitoring unit, that is, the first operation monitoring unit is connected to the slave terminal.
The changeover switch and the operation current limiting resistor are excluded. When the number of the second operation monitoring unit is one, the master terminal is connected to the slave terminal of the first operation monitoring unit through the control line, and when there is a plurality of slaves, the slave of the first operation monitoring unit is used. The terminal and the master terminal of the second operation monitoring unit located at the top order are connected via a control line, and the master terminal and the master terminals of the second plurality of second operation monitoring units located behind it are mutually connected. It is connected to and via the control line. Each common terminal of the first and second operation monitoring units is connected to an operation power supply via a common line.

In this case, when the changeover switch is switched to the control operation push button switch side, the operation control of the load can be performed only in the first operation monitoring section, and the operation can be performed from the second operation monitoring section due to the existence of the operation current limiting resistor. I can't control it. First
When the changeover switch of the operation monitoring unit is switched to the slave terminal side, the load operation control can be performed in common from each second operation monitoring unit without any priority.

Next, in the second means, each second operation monitoring unit has the same configuration as the first operation monitoring unit, that is, each second operation monitoring unit.
In the operation monitoring unit, each of the master terminals is connected in parallel to the slave terminal via a circuit in parallel with the changeover switch and the operation current limiting resistor when the master terminal is switched to the slave terminal side. Then, the slave terminal of the first operation monitoring unit and the master terminal of the second operation monitoring unit located in the first rank are connected via a control line, and in each second operation monitoring unit,
The slave terminal for the front direction and the master terminal for the rear direction are connected in a daisy chain through the control line. The common terminal of each second operation monitoring unit is connected to the operation power supply via a common line.

In this case, the operation switches of the first operation monitoring unit and the second operation monitoring unit are sequentially switched from the first order to the slave terminal side, so that the operation order of the immediately subsequent order has priority over the operation control of the load. It can be carried out.

[Operation] In the present invention having the above-mentioned configuration, the operation monitoring unit displays the operation of the load and the operating state of the failure, and controls the operation of the load as follows.

For convenience, the case where the operation monitoring unit is composed of the first and second operation monitoring units will be described.

1) Load stop (OFF) display First, assuming that the changeover switch of the first operation monitoring unit is not on the slave terminal side but on the control operation push button switch side and the load is in the stop (OFF) state, one of the control circuit The signal in the OFF state of logic 1 is input to the transmission photocoupler of the transmission / reception circuit.

Then, the current control transistor becomes conductive with the driving of the transmission photocoupler, and the threshold current setting resistance of the transmission / reception circuit is changed by the monitoring current limiting resistance of each operation monitoring unit and the operating current limiting resistance of the first operation monitoring unit in the operating circuit. A small current limited to a threshold current value set based on the current flows, and the current control transistor detects this and transmits it to the first and second operation monitoring units, and the OFF display light emitting diode of each operation monitoring unit. Lights up and it is displayed that the load is off.

2) Operation of load (ON) When the pushbutton switch for control operation of the first operation monitoring unit is turned on in this state, the monitoring current limiting resistor connected in parallel with it is short-circuited, so that the threshold current in the operating circuit is increased. A large current exceeding the value flows, the threshold current detection transistor detects this and drives the receiving photo coupler, and the receiving photo coupler outputs a control command by the push button switch to the control circuit.

The control circuit determines that the control command input when the load is in the OFF state is the ON command, and operates (ON) the load.

3) Load operation (ON) display When the load is operated, the control circuit inputs a logic 0 OFF signal to one of the transceiver circuits that had been inputting a logic 1 OFF signal and changes the current of this transceiver circuit. The light is turned off to turn off the light emitting diode for OFF display, and the signal of the ON state of logic 1 is input to the transmission photocoupler of the other transmission / reception circuit.

Then, as the transmission photocoupler is driven, the current control transistor becomes conductive, a current flows in the operation circuit, and the operation signal in the ON state is transmitted to the first and second operation monitoring units, and each ON signal is turned on.
The display light emitting diode is turned on to indicate that the load is in the ON state.

4) Stopping the load (OFF) When the push button switch of the first operation monitoring unit is turned off in this state, the monitoring current limiting resistance of each operation monitoring unit and the first operation monitoring unit are connected to the operation circuit via the other transmission / reception circuit. Since a small current equal to or less than the threshold current value flows due to the operation current limiting resistance of, each ON display light emitting diode remains lit.

When the push-button switch of the first operation monitoring unit is turned on again, the monitoring current limiting resistor connected in parallel with it is short-circuited, so that a large current exceeding the threshold current value flows in the other transmission / reception circuit. The threshold current detection transistor of the transmission / reception circuit detects and drives the reception photocoupler, and the reception photocoupler issues a control command by the push button switch to the control circuit.

The control circuit determines that the control command input when the load is in the ON state is the OFF command, and stops the load (OF
F)

5) Load stop (OFF) display When the load is stopped, the control circuit inputs the logic 0 ON signal to the other transmission / reception circuit that had input the logic 1 ON signal, and cuts off the current of this transmission / reception circuit. Then, the light emitting diode for ON display is turned off, and the OFF signal of logic 1 is input to one of the transmitting and receiving circuits, and accordingly, the light emitting diode for OFF display of the first and second operation monitoring units is turned on as described above. Then, it is displayed that the load is turned off.

6) Fault display of load Next, when the load fails (OFF) during operation (ON state), a flicker signal of a fault state of logic 1 is input from the control circuit to the other transmitting / receiving circuit. In this transmission / reception circuit, the current is intermittently turned on, and the ON display light-emitting diode of each operation monitoring unit is turned on / off in a blinking state.
A signal in the F state is input, and the O of each operation monitoring unit is accordingly
The FF display light emitting diode lights up, which indicates that the load is stopped (OFF) due to a failure.

Then, when the load failure is reset and reset, the control circuit stops the input of the flicker signal of the failure state to the other transmission / reception circuit, shuts off the current of this transmission / reception circuit, and accordingly displays ON. Since the flashing of the light emitting diode stops, this indicates that the fault condition of the load has been released.

The above is the case where the changeover switch of the first operation monitoring unit is on the control operation push button switch side. In this case, the operation circuit of the second operation monitoring unit is operated via the operation current limiting resistor of the first operation monitoring unit. Since it is connected to the transmission / reception circuit, even if the push button switch for control operation of the second operation monitoring unit is turned on, a current exceeding the threshold current value cannot flow in the transmission / reception circuit and the threshold current detection transistor is turned on. Therefore, the second operation monitoring unit cannot issue a load control command. That is, in this case, only the first operation monitoring unit closest to the transmitting / receiving device has the priority order of the load control operation.

7) Next, when the changeover switch of the first operation monitoring unit is changed over to the slave terminal side, the operation current limiting resistor connected in parallel with this switch is short-circuited. Therefore, in this case, by turning on the control operation push button switch of the second operation monitoring unit and short-circuiting the monitoring current limiting resistor connected in parallel with it, a large current exceeding the threshold current value can be supplied to the transmitting and receiving circuit. Therefore, it becomes possible to issue a load control command from the second operation monitoring unit.

In this case, if there are a plurality of second operation monitoring units and their respective master terminals are commonly connected to the slave terminals of the first operation monitoring unit via control lines, There is no priority between them, and each can issue a load control command in common.

Further, each second operation monitoring unit has the same structure as the first operation monitoring unit, and in each of the second operation monitoring units, the slave terminal of the front one closer to the first operation monitoring unit and the master terminal of the next one behind it are sequentially provided. If you connect them into a daisy chain,
By arranging the change-over switch of the first switch on the push-button switch side, it is possible to prioritize the load control commands. Then, by switching the order changeover switch to the slave side, the priority order can be moved backward.

[Embodiment] An embodiment of the present invention will be described with reference to FIGS.

FIG. 1 is a sequence circuit diagram of an opening / closing circuit of a three-phase general-purpose motor M and a remote monitoring device for monitoring the same. The opening / closing circuit of the motor M is the same as that of FIG. The monitoring device is a transmission / reception device 11 for controlling the motor M, and a first operation / operation monitoring unit which is connected to the transmission / reception device 11 in series via an operation power transformer 21 to display the operating state of the motor M or the operation state of failure and control operation. It comprises P ₁ and a plurality of second operation monitoring units P _{2 to} P _n connected in parallel with P ₁ .

The transmission / reception device 11 includes a voltage input circuit 17 connected to the switching circuit of the motor M, a control circuit 16, and a pair of transmission / reception connected to the control circuit 16 via signal input lines 20 and 18 and a control command output line 19. It is composed of circuits 12 and 13.

The R and S phases of the three-phase power supplies R, S, T of the motor M are also supplied to the operation power supply and control power supply of the monitoring device. That is,
The R phase and the S phase are connected to the primary side of the operation power transformer 21, the R phase is connected to the voltage input circuit 17 via the terminal T ₃ , and the S phase is the c contact of the thermal relay 51.
It is connected to the proposal pressure input circuit 17 via the b contact, the auxiliary normally open contact of the electromagnetic contactor 52, and the terminal T ₅ . The a contact of the thermal relay 51 is connected to the voltage input circuit 17 via the terminal T _6.
Connected to. The b contact of the thermal relay 51 is connected to the R phase via the coil of the electromagnetic contactor 52, the terminal T ₄ , the normally open contact of the output relay 52X of the electromagnetic contactor 52, and the terminal T ₃ .

As shown in FIG. 2, the transmitter / receiver circuit 12 includes a current control transistor Q ₁ , a threshold current detection transistor Q ₂ , a threshold current setting resistor R ₁ , a reception current limiting resistor R ₂ , a transmission photocoupler F _1, and a reception photocoupler F _1. Photocoupler F ₂ , current input terminal a ₂ and output terminal b ₂ , transmission signal input terminal c ₂
And a control command output terminal d ₂ .

The collector of the current control transistor Q ₁ is connected to the current input terminal a ₂ and the collector of the light receiving transistor of the transmission photocoupler F ₁ is connected via the reception current control resistor R ₂ . The emitter of the light receiving transistor is connected to the base of the current control transistor Q ₁ and the collector of the threshold current detection transistor Q ₂ . The emitter of the current control transistor Q ₁ is connected to the base of the threshold current detection transistor Q ₂ and is also connected to the current output terminal b ₂ via the threshold current setting resistor R ₁ . The emitter of the threshold current detection transistor Q ₂ is connected to the end of the threshold current setting resistor R ₁ on the side of the current output terminal b ₂ via the light emitting diode of the receiving photocoupler F ₂ . The light emitting diode of the transmission photocoupler F ₁ is connected to the control circuit 16 via the signal input terminal c ₂ in the operating state, while the light receiving transistor of the reception photocoupler F ₂ is output terminal d _{2 of the} control command signal.
Is connected to the control circuit 16 via. Signal input terminal c
_A signal indicating that the motor M (load) is stopped (OFF) is input to the control circuit 16 from the control circuit 16 via the signal input line 20. From the signal output terminal d ₂ , the operation control command of the motor M (load) from the first or second operation monitoring unit is output from the signal output line 1
It is sent to the control circuit 16 via 9.

The other transmission / reception circuit 13 also has the same circuit element as the one transmission / reception circuit 12 as shown in FIG. That is, the current control transistor Q ₃ and the threshold current detection transistor Q ₄ , the threshold current setting resistor R ₃ and the reception current limiting resistor ₄ , the transmission photocoupler F ₃ and the transmission photocoupler F ₄ ,
Further, it has a current input terminal a ₃ and an output terminal b ₃ , and a signal input terminal c ₃ and an output terminal d _3, and their mutual connection relationship is similar to that of the transmission / reception circuit 12. Signal input terminal c ₃ to be connected to the light emitting diode of the transmission photo coupler F ₃
A signal indicating that the motor M (load) is operating (ON) or a flicker signal indicating a failure is input from the control circuit 16 through the signal input line 18 to the signal output connected to the light receiving transistor of the receiving photocoupler F _4. From the terminal d ₃ ,
A load control command from the first or second operation monitoring unit is sent to the control circuit 16 via the signal output line 19.

However, in the pair of transmission / reception circuits 12 and 13, the current flowing through the circuit is in the opposite direction to the operating power source through one common line and the control line, and a pair of diodes connected in parallel in reverse polarity between them. So that they are connected in anti-parallel. That is,
One of the transceiver circuits 12 connects the current input terminal a ₂ to the cathode of the one diode 14 and connects it to one end on the secondary side of the operation power transformer 21 via a terminal T ₁ via a common line.
The current output terminal b ₂ is connected to the other end on the secondary side of the operation power supply transformer 21 via the terminal T ₂ , the control line, the first and second operation monitoring units, and the common line. On the other hand, the other transceiver circuit 1
3 connects the current input terminal a ₃ to the other end on the secondary side of the operation power supply transformer 21 via the terminal T ₂ , the control line, the first and second operation monitoring units, and the common line, and outputs the current output terminal b ₃ Is connected to the anode of the other diode 15 and is connected to one end on the secondary side of the operation power transformer 21 via a terminal T ₁ via a common line.

The first operation monitoring unit P ₁ and the second operation monitoring units P _{2 to} P _2
n is connected to the operation power supply transformer 21 in series with the pair of transmission / reception circuits 12 and 13 via one common line and one control line. The first operation monitoring unit P ₁ and the second operation monitoring units P _{2 to} P _n are connected in parallel.

The first operation monitoring unit P ₁ and the second operation monitoring units P _{2 to} P _n are, as shown in the first illustration, common terminals TC located at both ends, respectively.
₁ , TC _{2 to} TC _n and master terminals TA ₁ and TA _{2 to} T
A _n , light emitting diodes GL ₁ and GL _{2 to} GL for displaying operating states of a pair of loads connected in parallel with opposite polarities.
_n (OFF display) and _{RL 1, RL} 2 _~RL n (for ON display), changeover switches _{LS 1, LS} 2 _{~LS n} pushbutton and connected in series switch _{PB 1, PB} 2 _{~PB n} and monitoring current limit A parallel circuit with the resistors RA ₁ and RA _{2 to} RA _n ,
Slave terminals TB ₁ , TB _{2 to} TB _n , and a changeover switch L at the time of switching operation to the slave terminal side
S ₁ , LS _{2 to} LS _n and operating current limiting resistors PB ₁ , PB
_It has a parallel circuit with _{2 to} PB _n .

Light emitting diodes GL ₁ and GL ₂ for operation display of a pair of loads
One end of the reverse parallel circuit of the ～GL _n and _{PL 1,} RL 2 _{~RL n} is connected to the secondary side of the operating power supply transformer 21 via a common line to the common terminal _{TC 1, TC} 2 _{~TC n,} other end is connected in parallel circuit with said selector switch _{LS 1, LS} 2 _~LS push button switch _PB 1 _{to n} were connected in _series, PB 2 _{~PB n} monitoring current limiting resistor _{RA 1, RA} 2 _{~RA n} , This parallel circuit has master terminals TA ₁ , TA ₂
It is connected to the ~TA _n. This master terminal TA ₁ , T
A _{2 to} TA _n are changeover switches LS ₁ and LS _{2 to} LS _n at the time of the switching operation to the slave terminal side.
Is connected to the slave terminal _{TB 1, TB} 2 _{~TB n} via a parallel circuit of a an operation current limiting resistor _{RB 1, RB} 2 _{~RB n.}

The master terminal TA ₁ of the first operation monitoring unit P ₁ is connected to the current output terminal b ₂ and the current input terminal a _{3 of} the pair of transceiver circuits 12 and 13 via the control line and the terminal T ₂ , respectively.
Further, the slave terminal TB ₁ of the first operation monitoring unit P ₁ is connected to the master terminal TA ₂ of the second operation monitoring unit P ₂ immediately behind it via a control line, and the second operation monitoring unit P ₂ ~ P _n
The respective master terminals TA _{2 to} TA _n are connected to each other via a common line. That is, the second operation monitoring unit P ₂ to P _n, each master terminal is connected in parallel via a control line to a slave terminal TB ₁ of the first operation monitoring unit P _1, thus the first operation monitoring unit when the changeover switch LS ₁ of P ₁ is in the push button switch PB ₁ side, the second
The operation monitoring unit is the operation current limiting resistance P of the first operation monitoring unit P _1.
And thus it is connected to a pair of transmitting and receiving circuits 12 and 13 via the B _1.

Therefore, in the monitoring device according to the above embodiment, the motor M
The (load) is monitored as follows.

1) Stop (OFF) display First, the changeover switch LS _{1 of} each operation monitoring unit P _{1 to} P _n
To LS _n are on the push button switches PB _{1 to} PB _n side, and the motor M is stopped (OFF), the electromagnetic contactor 52.
Since the auxiliary normally open contact of is not opened, the potential from the S phase is not input to the voltage input circuit 17, so the control circuit 16 transmits the signal to the transmission photocoupler F ₁ via the signal input terminal c ₂ of the transmission / reception circuit 12.
Input the signal in the OFF state of logic 1 to. Then, the transmission photocoupler F ₁ is driven, and the current control transistor Q ₁
Is conducted and a current flows through the operating circuit.

That is, the operation circuit, the operation power transformer 21 diode 14 receiving circuit 12 monitors the current limiting resistor _RA 1 -O
FF display light emitting diode GL ₁ -Operation power supply transformer 2
A current flows in the direction of 1, and the light emitting diode G for OFF display
L ₁ lights up and the motor M in the first operation monitoring unit P ₁
The OFF state of is displayed.

The second operation monitoring unit _P 2 to P _n is a first operation monitoring unit _{P 1} connected in parallel, the master terminal _TA 2 to Ta _n, the slave terminal TB ₁ of the first operation monitoring unit _{P 1,} operating current limiting resistor RB
_1, because it is connected to the transceiver circuit 12 via the master terminal TA _1, OFF state of the second monitoring operation unit _P 2 to P even _n for OFF display light emitting diode GL2～GL _n lights motor M is displayed To be done.

The current flowing through the operation circuit at this time is the light emitting diode G.
Monitoring current limiting resistors RA _{1 to} R ₁ so that the total sum of the currents flowing in L _{1 to} GL _n is sufficiently smaller than the threshold current value set by the threshold current setting resistor R ₁ of the transmission / reception circuit 12.
Since the values of A _n and the operation current limiting resistor RB ₁ are set, the receiving photocoupler F ₂ of the transmitting / receiving circuit 12 is not driven by this circuit current, and the control command is not issued to the control circuit 16. Further, since the ON / OFF signal is not input to the transmission / reception circuit 13, the transmission / reception circuit 13 is in a non-conduction state.

2) Operation (ON) command In this state, when the push button switch PB ₁ of the first operation monitoring unit P ₁ is turned on, the monitoring current limiting resistor RA ₁ connected in parallel with the push button switch PB ₁ is short-circuited. A large current that exceeds the current value flows. That is, in the direction of the operation power transformer 21-diode 14-transmission / reception circuit 12-switching switch LS ₁ -push button switch PB _1- OFF display light-emitting diode GL ₁ -operation power transformer 21, a large current exceeding the threshold current value is detected. Flowing. Therefore, this is detected by the threshold current detection transistor Q ₂ , and the reception photocoupler F ₂ is driven by the current limited by the reception current limiting resistor R _{2 accordingly} , and the pushbutton switch PB _{1 is} input from the signal output terminal d _2. Control command based on the control circuit 16
Sent to.

The control circuit 16 determines that the control command input when the motor M is in the OFF state that does not depend on the failure, that is, when the thermal relay 51 is not operating on the side of the terminal T ₆ is the ON command, and sets the output relay 52X. Activate. Then, the normally open contact of the output relay 52X is closed, the coil of the electromagnetic contactor 52 is excited, the main contact of the electromagnetic contactor 52 is closed, power is supplied, and the motor M is operated.

3) ON display At this time, since the auxiliary normally open contact of the electromagnetic contactor 52 is closed and the S-phase potential is input to the voltage input circuit 17 via the terminal T ₅ , the control circuit 16 causes the signal of the transmission / reception circuit 12 to be transmitted. A signal in the OFF state of logic 0 is input to the input terminal c _2, and a signal in the ON state of logic 1 is input to the signal input terminal c ₃ of the transmission / reception circuit 13.

Then, the current of the transmission / reception circuit 12 is cut off, and the light emitting diode GL ₁ for OFF display is turned off. Then, the transmission / reception circuit 13 becomes conductive with the conduction of the current control transistor Q ₃ , so that the operation power supply transformer 21 is included in the operation circuit.
-ON display light emitting diode RL ₁ -Push button switch PB
₁ -switching switch LS ₁ -transmission / reception circuit 13-diode 15-operation current flows in the direction of the transformer 21,
The light emitting diode RL ₁ is turned on to indicate that the motor M is turned on.

At this time, no control command is output from the transmission / reception circuit 12, but since a current exceeding the threshold current value is flowing in the transmission / reception circuit 13, a control command of logic 1 is output from the signal output terminal d ₃ of the transmission / reception circuit 13. Has been issued.

4) Stop (OFF) command When the push button switch PB ₁ is turned off in this state, the operation power supply transformer 21-light emitting diode RL ₁ -monitoring current limiting resistance RA ₁ -transmission / reception circuit 13-diode 15-operation power supply transformer 21 direction A current flows and the light emitting diode RL
₁ is still lit and the ON state of the motor M is displayed. The ON state of the motor M indicates that the second operation monitoring unit P ₂
It is displayed by turning on the P _n even Likewise emitting diode _RL 2 _{~RL n.}

At this time, the currents flowing through the transmitting / receiving circuit 13 are the monitoring current limiting resistors RA ₁ to RA _{2 to} R _An and the operating current limiting resistor R.
Because of the small current below the threshold current value due to the limitation of B ₁ , the control command from the signal output terminal d ₃ of the phase receiving circuit 13 outputs logical 0, and the pushbutton switch PB ₁ is turned off in the control circuit 16. It is determined that the

Next, when the push button switch PB ₁ is turned on again while the motor M is in the ON state, the monitoring current limiting resistor RA ₁ connected in parallel with the push button switch PB ₁ is short-circuited, so that the threshold current is transmitted in the same direction to the transmission / reception circuit 13. A large current exceeding the value flows, and a control command of logic 1 is issued from the signal output terminal d ₃ to the control circuit 16.

When the control command is input while the motor M is in the ON state, the control circuit 16 determines that this is the OFF command, and turns off the output relay 52X. Then, the normally open contact is opened and the excitation of the coil of the electromagnetic contactor 52 is released, and the electromagnetic contactor 52 is released.
The main contact of is opened and the motor M is stopped (OFF).

5) OFF display At the same time that the motor M is turned off, the fact that the auxiliary normally open contact of the electromagnetic contactor 52 is opened and the motor M is turned off is input to the control circuit 16 via the voltage input circuit 17.

Then, the control circuit 16 turns ON the logic 0 to the transmission / reception circuit 13.
A state signal is input to make the transmitting / receiving circuit 13 non-conductive, and an OFF state signal of logic 1 is input to the transmitting / receiving circuit 12 to make the transmitting / receiving circuit 12 conductive. Along with it
The N display light emitting diodes RL _{1 to} RL _n are extinguished, and OF
The F display light emitting diodes GL _{1 to} GL _n are lit to indicate that the motor M is off.

At this time, since the current of the transmitter / receiver circuit 13 is cut off, the control command from the transmitter / receiver circuit 13 is not output, but a large current exceeding the threshold current value flows in the transmitter / receiver circuit 12, so that the transmitter / receiver circuit 12 outputs a logic signal. The control command of 1 is still issued.

Here, when the push button switch PB ₁ is turned off, the monitoring current limiting resistance operates and the current of the transmission / reception circuit 12 becomes a small current equal to or less than the threshold current value. Therefore, the output of the control command from the transmission / reception circuit 12 becomes logic 0. As a result, the control circuit 16 determines that the push button switch PB ₁ is turned off.

6) fault indication Incidentally, when the motor M is actuated thermal relay 51 becomes overloaded during operation (ON), the fault condition of the motor M via the terminal T ₆ closes its contact a simultaneous actuation thereof and Is input to the voltage input circuit 17. Along with this, the control circuit 16 turns off the output relay 52X to stop the operation of the motor M, and sends a flicker signal indicating a failure state to the signal input terminal c ₃ of the transmission / reception circuit 13.

On the other hand, as the excitation of the coil of the electromagnetic contactor 52 is released, its auxiliary contact opens and the OFF state of the motor M is input to the control circuit 16 via the voltage input circuit 17, so the control circuit 16 causes the transmission / reception circuit 13 to operate. The output of the ON-state signal for the signal is stopped and the OFF-state signal is output to the transmission / reception circuit 12. Along with this, the transmission / reception circuit 13 is intermittently turned on by the input of the flicker signal indicating the failure state, and the ON display light emitting diodes RL _{1 to} PL _{n of} each operation monitoring unit.
While blinking, the transmission / reception circuit 12 is turned on by the input of the OFF state signal and the OFF display light emitting diodes GL _{1 to} GL _{n of} each operation monitoring unit are turned on, so that the motor M is turned off due to a failure. Is displayed.

At this time, even if the push button switch of each operation monitoring unit is turned on, the control circuit 16 does not accept this command as long as the failure state is input.

Next, when the failure of the motor M is released and the thermal relay 51 is reset, its a contact opens and the voltage input circuit 17
A failure state reset signal is input to the control circuit 16 via the. Then, the control circuit 16 stops the output of the flicker signal of the failure state to the transmission / reception circuit 13 to make the transmission / reception circuit 13 non-conductive. Therefore, each of the ON display light emitting diodes RL _{1 to} RL _n stops blinking, turns off, and turns off.
Since the display light emitting diodes GL _{1 to} GL _n are still lit, the failure of the motor M is canceled by this, and O
It is displayed that it is in the FF state.

The above is the changeover switch L of the first operation monitoring unit P _1.
When S ₁ is on the push button switch PB ₁ side, in this case, the motor M is turned on only from the first operation monitoring unit P ₁ .
An OFF command can be issued, and the second operation monitoring units P _{2 to} P _2
You can't get out of _n .

That is, the second operation monitoring unit _P 2 to P _n are each push-button switch PB
_{2 to} PB _n and monitor current limiting resistor RA in parallel with it
_{Even if 2 to} RA _n are short-circuited, the transmission / reception circuit is connected to the transmission / reception circuit via the operation current limiting resistor RB ₁ of the first operation monitoring unit P ₁ , so that the transmission / reception circuit circuit 12 or 13 is provided with the threshold current value. This is because the above current cannot flow.

7) Priority of ON / OFF command However, the changeover switch L of the first operation monitoring unit P ₁
When S ₁ is switched to the slave terminal TB ₁ side, the operation current limiting resistor RB ₁ is short-circuited by this, and the second operation monitoring units P _{2 to} P _n are connected to the transmission / reception circuit without being restricted. Therefore, each push button switch P
B ₂ ~PB putting _n each monitoring current limiting resistor _RA 2 to RA
By shorting _n , the transmitter / receiver circuit 12 or 13
A current exceeding the threshold current value can be applied to
The second operation monitoring units P _{2 to} P _n also turn on and off the motor M.
It is possible to issue an F command.

However, when the master terminals TA _{2 to} TA _n of the second operation monitoring unit are commonly connected to the slave terminal TB ₁ of the first operation monitoring unit via the control line as shown in the first diagram, no priority control command of the motor M between the second operation monitoring unit P ₂ to P _n, can be respectively put to equally control command.

On the other hand, although not shown, the second operation monitoring unit P ₂
As with the first operation monitoring unit _{P 1} between to P _n of the second operation monitoring section _{P 2,} in front of the position the slave terminal TB ₂
~ TB _n and the master terminals TA _{3 to} TA _{n + 1 at the} next position are sequentially connected to form a string of beads,
Similarly to the above, the operation current limiting resistance RB _{2 of} parallel connection accompanying the switching operation of the preceding changeover switches LS _{2 to} LS _n
~ Depending on the presence / absence of a short circuit in RB _n , the possibility of control operation of the motor M is gradually lowered to the subsequent one, that is, the priority order of the control command of the motor M is transmitted / received between the second operation monitoring units. It can be given in order of proximity to the device.

[Advantages of the Invention] Since the present invention has the above-described configuration, it has the following advantages.

a. Since a pair of transceiver circuits consisting of two resistors, two transistors, and two photocouplers are used as a transceiver device that transmits a signal of the operating state of the load and receives a control command, the sequence of the monitoring device is used. The circuit can be made electronic, and accordingly, the configurations of the transmission / reception device and the operation monitoring unit can be simplified and the number of connection wirings can be reduced.

In addition, a low-voltage AC power supply can be used as the operation power supply, and the wiring structure is simple, which makes the system safer than before.

b. A pair of transmission / reception circuits and a pair of light emitting diodes are connected in parallel in opposite polarities respectively to distinguish the ON / OFF state signal transmission directions, and the ON state display light emitting diode blinks using a flicker signal as a failure state signal. The failure status can be displayed by means of the single wire control system in which the transmitter / receiver and the operation monitoring section are connected by a single wire without the need for a member for transmitting and displaying the failure status signal. Not only ON / OFF display but also failure display is possible.

c. Both signals are sent by detecting the presence or absence of a circuit current below the threshold current value when transmitting the signal indicating the operating state of the load, and by detecting the presence or absence of a circuit current above the threshold current value when outputting the control command. The control circuit determines whether the control command is ON or OFF according to the operating state of the load. Therefore, the operating state of the load can be checked by the single wire control method and the operation of a single push button switch. The display can be turned on and off.

d. The control circuit that controls the load and the operation circuit that sends the signals and issues the control command are insulated by a photocoupler, and the output of the load control command that requires a greater noise margin is larger than the signal transmission current. The operation is performed with a current equal to or higher than the threshold current value, and a large noise margin can be secured by setting the threshold current value, so that the stability and reliability of operation are good.

e. When each operation monitoring unit is further provided with a changeover switch, an operation current limiting resistor, and a slave terminal, and the slave terminal at the front position and the master terminal at the next rear position are sequentially connected through the control line and connected in a daisy chain. In addition, the control operation for the load can be prioritized in the order of being closer to the transmitter / receiver by the switching operation of the changeover switch, which is safe in use.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sequence circuit diagram of a remote monitoring apparatus according to an embodiment of the present invention, FIG. 2 is a circuit diagram of a pair of transmitting / receiving circuits in the transmitting / receiving apparatus in the same circuit diagram, and FIG. FIG. 7 is a sequence circuit diagram showing an example of a conventional device. M ... Motor, 11 ... Transceiver 12, 13 ... Transceiver circuit 14, 15 ... Diode 16 ... Control circuit, 17 ... Voltage input circuit 18 ... Signal input line 19 ... signal input line 21 ...... operation of the control command output lines 20 ...... OFF state power transformer _{a 2,} a ₃ ...... current input terminal b _{2, b 3} ...... current output terminal c _{2, c 3} ...... transmission signal input terminal d ₂ , d ₃ ... control command output terminals Q ₁ , Q ₃ ... current control transistors Q ₂ , Q ₄ ... threshold current detection transistors R ₁ , R ₃ ... threshold current setting resistance R ₂ , R ₄ ...... Reception current limiting resistance F ₁ , F ₃ ...... Transmission photocoupler F ₂ , F ₄ ...... Reception photocoupler P ₁ ...... First operation monitoring unit P _{2 to} P _n ...... Second operation monitoring unit TA _1- TA _n ... Master Terminals TB _{1 to} TB _n ...... Slave terminals TC _{1 to} TC _n ...... Common terminals GL _{1 to} GL _n ...... OFF light emitting diodes RL _{1 to} RL _n・ ・ ・ ON light emitting diodes PB _{1 to} PB _n ...... Push button switch LS _{1 to} LS _n ...... Changeover switch RA _{1 to} RA _n ...... Monitoring current limiting resistance RB _{1 to} RB _n ...... Operating current limiting resistance

Claims (3)

[Claims] 1. A transmission / reception device connected to an opening / closing circuit for a load such as a motor and connected to a transmission / reception device connected in series to an operation power source for displaying the operating state of a load such as a motor or the like and displaying operation control. In the remote monitoring device that operates via the operation monitoring unit, the transmission / reception device detects the signal of the operating state of the operation of the load such as the motor or the failure via the voltage input circuit, transmits the signal, and inputs the signal. A control circuit that controls the operation of the load based on the signal of the operation control command of the load, and a signal of the operating state of the load sent from this control circuit to the operation monitoring unit, and the operation control of the load sent from the operation monitoring unit And a pair of transmission / reception circuits that detect a command signal and send it to the control circuit. The pair of transmission / reception circuits respectively include a current input and output terminal, a signal input and output terminal, and a current control transistor. Transistor, threshold current detecting transistor, threshold current setting resistor, receiving current limiting resistor, and transmitting and receiving photocoupler circuit elements. In these circuit elements, the collector of the current control transistor is the current input terminal. Connected to the collector of the phototransistor of the transmission photocoupler through the reception current limiting resistor, the emitter of the phototransistor is connected to the base of the current control transistor and to the collector of the threshold current detection transistor, The emitter of the current control transistor is connected to the base of the threshold current detection transistor and to the current output terminal through the threshold current setting resistor, and the emitter of the threshold current detection transistor is the light emitting diode of the receiving photocoupler. Current output of the threshold current setting resistor via The light-emitting diode of the transmitting photocoupler is connected to the control circuit via the signal input terminal in the operating state, while the light-receiving transistor of the receiving photocoupler is connected to the control circuit via the output terminal of the control command signal. And a pair of transmission / reception circuits each of which is composed of a combination of such circuit elements, has one common line and control line for the operating power supply,
In the meantime, it is connected in anti-parallel so that the current directions are opposite via a pair of diodes connected in parallel with opposite polarities, that is, in one transceiver circuit, the current input terminal is connected to the cathode of one diode. Connected to one end on the secondary side of the operating power supply via a common line, and the current output terminal is connected to the other end on the secondary side of the operating power supply via the control line, the operation monitoring section and the common line, and the other end. In the transceiver circuit, the current input terminal is connected to the other end of the secondary side of the operating power supply via the control line, the operation monitoring unit and the common line, and the current output terminal is connected to the anode of the other diode to connect the common line. It is connected to one end on the secondary side of the operation power supply, and the operation monitoring unit is for displaying the operating status of the common terminal and the master terminal located at both ends, and a pair of loads connected in parallel with opposite polarities. Light emitting diode, monitoring power connected in parallel It has a current limiting resistor and a circuit element of a push button switch for control operation.One end of the common terminal is connected to one end on the secondary side of the operating power supply via a common line and the other end is connected to the pair of light emitting diodes. Connected to an anti-parallel circuit, the other end of the anti-parallel circuit of the light emitting diode is connected to the parallel circuit of the monitoring current limiting resistor and the push button switch for control operation, and the other end of the parallel circuit is connected to the master terminal. In addition, the other end of the master terminal of the operation monitoring unit is connected to each of the current input terminal and the output terminal of the pair of transmission / reception circuits via a control line. 2. An operation monitoring unit for connecting an operation power source in series with a transmitter / receiver, comprising a first operation monitoring unit and one or more second operation monitoring units connected in parallel with the first operation monitoring unit. The first operation monitoring unit is provided with an anti-parallel circuit of a pair of light emitting diodes for displaying an operation state of a load connected to an operation power supply via a common terminal and a common line, a control operation push button switch and a push button switch side for the control operation. The parallel circuit of the changeover switch and the monitoring current limiting resistor connected in series during the changeover operation of is connected, and the other end of this parallel circuit is connected to the master terminal connected to the transmitter / receiver via the control line, and this master Further, the terminal is connected to the slave terminal through a parallel circuit of a changeover switch and an operation current limiting resistor at the time of switching operation to the slave terminal side, while the second operation monitoring unit is Between the common terminal connected to the operating power supply via a conductor and the master terminal, an anti-parallel circuit of a pair of light-emitting diodes for displaying the operating state of the load, a control push button switch and a monitoring current limiting resistor in parallel. If one or a plurality of connected circuits are arranged and the number of the second operation monitoring unit is one, connect the master terminal to the slave terminal of the first operation monitoring unit via the control line. When there are a plurality of second operation monitoring units, the slave terminal of the first operation monitoring unit and the master terminal of the second operation monitoring unit located in the first rank are connected via a control line, and the masters thereof are connected. 2. The remote monitoring device according to claim 1, wherein the terminal and the respective master terminals of the next plurality of second operation monitoring units located behind the terminal are connected via a control line. 3. A second monitor connected in parallel to the first operation monitor, the changeover switch and the operation current limit when the master terminal is further switched to the slave terminal side, as in the first operation monitor. A plurality of those connected to a slave terminal via a parallel circuit with a resistor are arranged and used, and each second operation monitoring section is connected to an operation power supply via each common terminal and a common line, The slave terminal and the master terminal of the second operation monitoring unit located at the top order are connected via the control line, and the front order and the plurality of second operation monitoring units located behind the first operation monitor 3. The remote monitoring device according to claim 2, wherein the slave terminal and the master terminal for the next rearward direction are sequentially connected via a control line to connect the respective second operation monitoring units in a daisy chain.