JP2003150244A - Device for output equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a slave capable of continuously operating an alarm means for specifying output equipment whose short circuit is occurred even at turning off a power source for the output equipment. SOLUTION: This device is provided with an output circuit 16 for turning ON/OFF an OUT terminal 16" and an internal circuit including an MPU 13 for controlling the operation of an output circuit (transistor 16') according to a control instruction from a PLC. The internal circuit and an output circuit are constituted to receive power supply from power feedlines in different systems, and the transistor outputs a short-circuit detection signal to the MPU at detecting the short-circuit. At receiving the short-circuit detection signal, the MPU turns ON a short-circuit buffer, and turns ON a relevant status LED 20. The MPU obtains the operating state of an I/O power source 19 through a photo-coupler 15c, and holes the short-circuit buffer in the ON state even when the power source is turned off. Therefore, the status LED can be lighted even when the power source is turned off.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for output equipment.

[0002]

2. Description of the Related Art An example of a network system including a PLC is shown in FIG. That is, PL
The C unit 1 and the master unit 2 having a communication function are integrated, and the master unit 2 is connected to the field network 3. The OUT slave 4 and the like are connected to the field network 3. In this example, the OUT terminal of the OUT slave 4 is connected to the output device 5 such as a valve or a motor.

The internal structure of the OUT slave 4 is as shown in FIGS. 2 and 3, for example. That is, a communication interface (communication connector) 4a for connecting to the field network 3 is provided, and a frame, message, etc. addressed to itself, which is received via this communication interface 4a, is analyzed by the communication unit 4b and necessary information is obtained. MPU4c
Given to. Upon receiving OUT data from the master unit 2, the MPU 4c turns on the corresponding OUT terminal.
Send a control signal to turn off / off. Specifically, ON
The / OFF information (1/0) is written in the flip-flop 4d.

The output of the flip-flop 4d (equivalent to the value of the given control signal) is given to the short circuit detection built-in output circuit 4f via the photocoupler 4e. As shown in FIG. 3, the short-circuit detection built-in output circuit 4f includes a transistor 4f 'having a short-circuit prevention function.
By turning on / off f ', the OUT terminal 4f "to which the output device is connected is turned on / off.

Further, the line for transmitting the control signal has an OU
I / indicating the state of the T terminal 4f ″ (contact ON / OFF)
It is equipped with O_LED 4g. This I / O_LED 4g
Lights up when the control signal is ON, or changes the color that lights up depending on ON / OFF.

Further, the illustrated OUT slave 4 is
It is divided into an internal circuit that performs signal processing and the like and an output circuit that drives and operates the output device 5, and each circuit is driven by a different power source. That is, the output circuit is adapted to receive power from the external I / O power supply 4i, and the transistor 4f 'described above is provided in this power supply line. As a result, when the transistor 4f 'is turned on based on the control signal, the circuit is closed and I
/ O power supply 4i to OUT terminal 4f ″ and then output device 5
Is energized. Further, the I / O power supply 4i is provided with a switch 4i ', and by opening / closing this switch 4i', ON / OFF of the power supply of the entire output circuit can be managed.

On the other hand, the electric power is supplied to the internal circuit from the internal circuit power source 4h. The internal circuit power source 4h may be, for example, an independent power source, or may be the one supplied through the field network 3 as appropriate. It may be converted and supplied to each element or the like forming the internal circuit in the OUT slave 4.

Further, although the illustrated OUT slave 4 has the short-circuit preventing function as described above, specifically, the transistor 4f 'determines whether or not the output device 5 connected thereto is short-circuited. When a short circuit is detected, the contact is turned off and a short circuit detection signal is output. That is, when the output device 5 is short-circuited, a large short-circuit current flows and heat is generated along with the energization. Therefore, by detecting such an overcurrent or heat generation, it is determined that a short circuit has occurred and a predetermined operation is performed.

The short circuit detection signal is sent to the photocoupler 4
It is given to the bus buffer 4j via e and transmitted to the MPU 4c at a predetermined timing. Further, the MPU 4c which receives the short circuit detection signal is, for example, via the field network 3 the master unit 2 and then the PLC.
Send to unit 1. As a result, the PLC unit 1 performs processing for turning on a predetermined alarm lamp or sounding an alarm buzzer, and notifies that there is an abnormality.
Also, in some cases, abnormal processing such as stopping the system is performed.

As described above, in the case of such a system, when the output device is short-circuited, the upper PLC or the like is notified, and an alarm is output from the upper PLC or the like to notify an observer or the like of the abnormality. Therefore, it is possible to perform maintenance such as replacement work of the output device in which the worker short-circuits by going to the site where the short circuit has occurred quickly.

[0011]

However, the system including the OUT slave to which the conventional short-circuit detecting function is added has the following problems. That is, when performing maintenance (repair, replacement work) of an output device (load) that is short-circuited, the switch 4i 'is normally opened to prevent danger due to malfunction.
Maintenance work is performed with i turned off.

As is clear from the circuit configuration shown in FIG. 3, when the I / O power supply 4i is turned off in this way, the transistor 4f 'is not energized. As a result, overcurrent disappears and heat generation disappears, so it is determined that there is no short circuit, and the short circuit detection signal is turned off. As a result, the MPU 4c that is operating by being supplied with power from the internal circuit power supply 4h determines that the short circuit has been resolved, and performs the predetermined operation associated with the resolution.

That is, for example, the PLC unit 1 is notified of the elimination of the short circuit, and accordingly, the PLC unit 1 is notified.
Will start normal cyclic control. However, since the short-circuited state is not actually solved, there is a risk of malfunction. Further, for example, when a lamp (status LED) for identifying a short-circuited terminal is turned on according to a control command from the PLC unit 1 or a command from the MPU 4c, the lamp is turned off together with the I / O power supply 4i being turned off. Also, since the worker turns off the light, it is not possible for the worker to determine in which output device the short circuit has occurred based on whether or not the lamp is turned on, and the process of identifying the maintenance target becomes complicated.

Therefore, according to the present invention, even if the power supply for the output device is turned off, the output device (OU
It is an object of the present invention to provide an apparatus for an output device capable of continuing to operate an alarm means for specifying (T terminal) and facilitating specification of a maintenance target.

[0015]

An apparatus for output device according to the present invention is used for a PLC system, for example, and is an apparatus for output device having an output terminal for connecting an output device. Then, turn on the output terminal
An output circuit for turning on / off and an internal circuit including a control means for controlling the operation of the output circuit, and the internal circuit and the output circuit are configured to be supplied with power from power supply lines of different systems, respectively. The output circuit has a function of outputting an abnormality detection signal to the control unit when an abnormality is detected, and the control unit outputs an output for operating an alarm unit when the abnormality detection signal is received. Outputs a signal and monitors the ON / OFF state of the power supply line for the output circuit, and continues to output the output signal immediately before the power supply line is turned off even if the power supply line is turned off. Configured to do so.

Further, preferably, the control means may have a function of canceling the output of the output signal when the power supply line is returned from OFF to ON. Of course, such a function may not be necessary.

As another means for solving the problems, an output circuit for turning ON / OFF the output terminal and an internal circuit including a control means for controlling the operation of the output circuit are provided, and the internal circuit and the output circuit are respectively provided. The output circuit is configured to receive power from a power supply line of another system, and the output circuit has a function of outputting an abnormality detection signal to the control unit when an abnormality is detected, and the control unit is configured to output the abnormality. When the detection signal is received, the output signal for operating the alarm means is continuously output, and the ON / OFF state of the power supply line for the output circuit is monitored to turn the power supply line from OFF to ON. The configuration is such that the output of the output signal is canceled when the signal returns.

In the embodiment, the control means is the MPU 13,
In the embodiment, the alarm means corresponds to the status L.
Corresponds to ED. This alarm means can identify which output terminal (output device) has an abnormality.

The output device is, for example, a slave (OUT slave, MIX slave, or the like), or an output unit for configuring a PLC formed by connecting a plurality of units.

According to the present invention, when an abnormality such as a short circuit occurs in the output device or the like, the output circuit detects it and outputs an abnormality detection signal. When the control means receives the abnormality detection signal, it outputs an output signal to operate the alarm means. As a result, the worker, the monitor, etc. can know that there is an abnormality.

Next, when performing the maintenance process to eliminate the abnormality, the power supply to the output circuit is turned off.
Then, the output circuit also stops and the abnormality detection signal turns off, but even in this case, since the power supply for the internal circuit is continued, the control means operates normally and continues to output the output signal. The means continues to operate (alarm output).

Each means constituting the apparatus for output device according to the present invention can be realized by a dedicated hardware circuit or can be realized by a programmed computer.

[0023]

FIG. 4 and FIG. 5 show a preferred embodiment of a slave according to the present invention. This slave is connected to the field network as shown in FIG. 1, performs master-field communication with the master, transmits / receives I / O data, and outputs a short circuit detection signal to the master unit. I'm supposed to do it.

The basic structure of the internal structure is the same as the conventional one. That is, a communication interface (communication connector) 1 for connecting to the field network
1, the frame, message, etc. addressed to itself received via the communication interface 11 are analyzed by the communication unit 12, and necessary information is given to the MPU 13.

The MPU 13 is connected to an 8-bit bus and transmits / receives data via the bus. In other words, this bus has two flip-flops 14a and 14c.
, One bus buffer 14b is connected to
The U13 transmits / receives data to / from one of the flip-flops 14a and 14c and the bus buffer 14b (flip-flops 14a and 14c).
To write data to and read data from the bus buffer 14b).

Then, the MPU 13 writes the OUT data received from the master unit in a predetermined address of the flip-flop 14a. Each output of the flip-flop 14a is given to the base of each transistor 16 'constituting the short circuit detection built-in output circuit 16 via the photocoupler 15a, and turns on / off the transistor 16'. Since an I / O power source 19 is connected to each transistor 16 ', the ON / OFF of the transistor 16' causes the OUT terminal 16 ", which is an I / O terminal connected to the transistor 16 ', and thus its terminal. The output device 25 connected to is turned on / off.
A switch 19 'is installed on the / O power supply 19 so that the I / O power supply can be shut off entirely.

Further, the line for transmitting the control signal has an OU
I / indicating the state of the T terminal 16 "(contact ON / OFF)
The O_LED 17 is connected. This I / O_LED
17 is lit when the control signal is ON, ON / OF
The color that lights up is changed by F.

Furthermore, the slave 10 is divided into an internal circuit for performing signal processing and the like, and an output circuit for driving and operating the output device 25, and each circuit is driven by a different power source. . That is, the output circuit (transistor 16 ') is configured to receive power from the external I / O power source 19, as described above. Then, power is supplied to the internal circuit from the internal circuit power supply 18. The internal circuit power supply 18 is, for example,
An independent power source may be used, or the power supplied via the field network may be appropriately converted and supplied to each element or the like forming the internal circuit in the slave 10.

Further, the transistor 16 'has a short-circuit prevention function, detects a short circuit of the output device 25 connected to itself, and when it detects, turns off the contact and outputs a short-circuit detection signal. . That is, the output device 25
When is short-circuited, a large short-circuit current flows and heat is generated as the current flows. Therefore, by detecting such an overcurrent or heat generation, it is determined that a short circuit has occurred, and the contact OFF processing and short circuit detection signal output processing described above are performed.

This short circuit detection signal is supplied to the photocoupler 15b.
Is given to the bus buffer 14b via the and is transmitted to the MPU 13 at a predetermined timing. The MPU 13, which has received the short-circuit detection signal, has the corresponding flip-flop 14
The input terminal of c is turned on, and the flip-flop 14c
The status LED 20 connected to is turned on. Thus, by checking which status LED 20 is lit, it is possible to easily recognize which output device 25 is short-circuited. Further, the MPU 13 notifies the master unit and eventually the PLC unit that a short circuit has occurred via the field network.

Here, in the present invention, the power supply line from the I / O power supply 19 is branched and supplied to the MPU 13 via the photocoupler 15c. That is, when the I / O power supply 19 is turned on and power is being supplied,
The output of the photocoupler 15c is turned on.

When the switch 19 'is opened to turn off the I / O power source 19 for maintenance or the like, the output of the photocoupler 15c is also turned off. Therefore, MPU
In 13, the operating state of the I / O power supply 19 can be recognized by monitoring the output (I / O power supply detection signal) of the photocoupler 15c.

Therefore, in the present embodiment, the MPU 13
When the power is turned off, the status LED 20 is kept lit when the short circuit detection signal is being output (just before) when the power is turned off. That is, the transistor 1 is turned off when the I / O power supply 19 is turned off.
Since the short-circuit detection signal from 6'is also turned off, the MPU 13 normally judges that the short-circuit state has disappeared and turns off the status LED 20, but the I / O power supply 19 turns off.
In the case of FF, the detection signal is also turned off due to the loss of the power supply, and it is determined that the short-circuited state is actually continuing, and the status LED 20 is operated to continue lighting. As a result, even if the I / O power supply 19 is turned off for maintenance, the predetermined status LED 20 is lit, so that the OUT terminal (output device) that has a short circuit can be easily specified.

In order to realize the above processing function, MP
U13 is added with a function for implementing the flowchart shown in FIG. First, the MPU 13 uses the bus buffer 14
It has a function of taking in each value of b and judging whether or not the short-circuit detection signal is output from the transistor 16 ', and further, it becomes possible to set the state of whether or not to carry out such judgment (short-circuit detection). There is. That is, when the short-circuit detection is valid, the value of the bus buffer 14b is actually fetched and it is determined whether or not there is a short circuit. In other words, if the short circuit detection is disabled, regardless of whether the short circuit detection signal is ON or OFF,
Does not judge whether there is a short circuit. Of course, the validity / invalidity of this short circuit detection is switched and set for each bit.

The MPU 13 operates as follows by using the above-mentioned function of judging the short circuit detection and the function of switching the valid / invalid of the short circuit detection. First, it is determined whether or not the short circuit port detects a short circuit (ST1). This determination is Yes when the short circuit detection is valid and the corresponding bit of the bus buffer 14b is ON (the transistor 16 'outputs the short circuit detection signal). Then, in other cases, that is, when the corresponding bit of the bus buffer 14b is OFF (no short circuit has occurred) even if the short circuit detection is valid, and when the short circuit detection is set to invalid, the step 1 The branch determination is No. If the branch determination in step 1 is Yes, the corresponding short-circuit detection buffer in the MPU 13 is turned on (ST2). As a result, the ON state is latched.

Next, the output of the photocoupler 15c, that is, the ON / OFF signal of the I / O power supply detection signal is acquired, and I / O is detected.
Check the state of the O power source (ST3). If the previous state is OFF and this time is ON, it can be determined that the power is turned on. Therefore, the process proceeds to step 4, and the short circuit detection buffer is turned off all at once, and all output devices (OUT
The status for (terminal) is set to no short circuit. As a result, all the bits of the flip-flop 14c are turned off and the status LED 20 is turned off. After that, set the short circuit detection to be effective for all short circuit ports (S
T5), preparing for the next monitoring.

On the other hand, ON / OFF of the I / O power supply detection signal
When the signal is in a state other than the above-mentioned state, that is, when it is OFF, or when both the previous time and the current time are ON, the process proceeds to step 6, and ON / OFF of the short circuit detection buffer is reflected in the status. Actually, the status in which the short circuit detection buffer is ON is reflected in the status as a short circuit. This caused an output device (OUT terminal) that caused a short circuit.
The corresponding bit of the flip-flop 14c connected to the status LED 20 assigned to
The corresponding status LED 20 lights up.

By executing the above-mentioned flowchart, the short circuit detection is enabled in the initial state, and once the short circuit is detected, the short circuit detection buffer is turned on (ST
2) When a short circuit is reflected in the status and the corresponding status LED 20 is turned on (ST6), the short circuit detection is invalidated (ST7). Therefore, the status determination of the short circuit boat itself is not performed until the short circuit detection is validated in step 5, and the status LED 20 continues to be in the lighting state.

On the other hand, step 5 is executed when the I / O power supply 19 is turned off and then turned on. Therefore, the short circuit detection remains ineffective only when the I / O power supply 19 is turned off for maintenance or the like, and the status LED 20 continues to be lit.

When the I / O power supply 19 is turned on after the maintenance is completed, the short circuit detection buffers are turned off all at once.
Therefore, the status LED 20 is also turned off. After that, since the short-circuit detection is enabled (ST5), if the replaced output device or other output device is short-circuited, the corresponding status LED 20 is turned on again.

The operation of the above embodiment will be described with reference to the time chart shown in FIG. That is, since the I / O power supply is ON in the normal state, I / O
The power supply detection signal also turns ON. And the short circuit detection signal is also O
Since it is FF, the short circuit detection signal buffer is also turned off, and the status LED 20 is turned off.

In this state, if a short circuit occurs at the timing (1), the short circuit detection signal is turned on, so that the branch determination in step 1 is Yes (short circuit detection is effective in the initial state). Along with this, the short-circuit detection holding buffer is turned on, and the status LED 20 is tracked accordingly.
Also lights up.

Next, when the I / O power supply is turned off for maintenance at timing (2), the I / O power supply detection signal is also turned off. Further, since the transistor 16 'is not energized, the short circuit detection signal is also turned off. However, since the output of the short circuit detection signal holding buffer remains latched ON, the status LED 20 also keeps lighting. Thus, since the status LED 20 is still lit while the I / O power supply 19 is off, it is possible to easily identify the location where the short circuit has occurred by checking which one is lit.

At timing (3), the maintenance work is completed (replacement with a normal output device, etc.) and the I / O power supply 19 is turned on. Then, steps 4 and 5 are executed and the short-circuit detection signal holding buffer is Turns off. In addition, the status LED 20 is also turned off accordingly, and the normal state is restored.

Although the above embodiment has been described with respect to the OUT slave to which the output device is connected, it is of course applicable to a mixed type MIX slave to which the input device is also connected.

8 and 9 show another embodiment of the present invention. The present embodiment is different from the above-described embodiments and shows an example applied to an output unit forming a PLC. That is, as is well known, there is one in which a unit for each function is prepared and units having necessary functions are connected to form one PLC. In FIG.
An output unit 3 for connecting an output device to the base 30
1, an input unit 32 for connecting an input device, a CPU unit 33 for executing a user program, and a power supply unit 34 for supplying power for driving each unit. Each unit is connected by a bus, and data is transmitted and received between the units and power is supplied. Of course, it is not necessary to mount all the illustrated units, and other types of units may be connected.

An example of the internal structure of the output unit 31 is shown in FIG. An interface 41 is provided for connecting each unit that constitutes the PLC to a PLC bus that electrically connects the units. This interface 4
1, an MPU 43 is connected, and this MPU 43
Transmits and receives data to and from other units via the interface 41.

Further, the MPU 43 is connected to an 8-bit bus, and two flip-flops 4 are connected via the bus.
Data is transmitted and received between 4a and 44c and one bus buffer 44b.

The MPU 43 has the CPU unit 3
OUT data sent from 3 is flip-flop 4
It has a function of writing to a predetermined address of 4a. The outputs of the flip-flops 44a are supplied to the respective transistors 4 forming the short-circuit detection built-in output circuit 46 via the photo coupler 45a.
6 ', and its transistor 46' is turned on.
N / OFF.

Further, each transistor 46 'has an I / O.
Since the power supply 49 is connected, turning on / off the transistor 46 'turns on / off the OUT terminal 46 "connected to the transistor 46' and thus the output device 51 connected to the OUT terminal 46". Also in this embodiment, the switch 49 ′ is installed in the I / O power source 49,
The I / O power supply can be shut off entirely.

Further, the line for transmitting the control signal has an OU
I / indicating the state of the T terminal 46 "(contact ON / OFF)
The O_LED 47 is connected. This I / O_LED
47 is turned on when the control signal is ON, or ON / OF
The color that lights up is changed by F.

Furthermore, the output unit 31 is divided into an internal circuit for performing signal processing and the like and an output circuit for driving and operating the output device 51, and each circuit is driven by a different power source. There is. That is, the output circuit (transistor 46 ') is configured to receive power from the external I / O power supply 49, and power is supplied to the internal circuit via the PLC bus. Therefore, I / O
When the power supply 49 is turned off, the power supply to the output device 51 is cut off, but the internal circuit operates.

Further, the transistor 46 'has a short-circuit prevention function, detects a short circuit of the output device 51 connected to itself, and when detecting it, turns off the contact and outputs a short-circuit detection signal. .

This short circuit detection signal is supplied to the photo coupler 45b.
To the MPU 43 at a predetermined timing. The MPU 43 receiving this short-circuit detection signal, the corresponding flip-flop 44
Turn on the input terminal of c, and flip-flop 44c
The status LED 50 connected to is turned on. Thus, by checking which status LED 50 is lit, it is possible to easily recognize which output device 51 is short-circuited.

In the present invention, the power supply line from the I / O power source 49 is branched and supplied to the MPU 43 via the photocoupler 45c so that the state of the I / O power source 49 can be detected. When the I / O power is turned off, the MPU 43 outputs the status LED 50 when the short-circuit detection signal is being output (just before) when the I / O power is turned off.
Is configured to continue to light. Specifically, it is realized by incorporating a function for implementing the flowchart shown in FIG.

The output circuits 16 and 46 with built-in short circuit detection (transistors 16 'and 4) according to the above-described embodiments.
As shown in the timing chart of FIG. 7, 6 ') outputs a short-circuit detection signal while detecting the short-circuit (O
N) is continued, but such a configuration may not necessarily be adopted, and a single pulse may be output when a short circuit occurs. That is, in the above-described embodiment, as shown in the flowchart of FIG. 6, once the short circuit is detected, the state is latched and the short circuit detection is disabled thereafter, so that the MPU is notified of the short circuit. In this case, the status LED is not required to continue to output the short circuit detection signal after that.
This is because it is possible to keep lighting 20 and 50.

Further, in the flow chart shown in FIG. 6, once a short circuit is detected, thereafter, it is not monitored whether or not the short circuit detection signal is output even when the I / O power supply is ON,
It is estimated that there is a short circuit, and the short circuit detection buffer is turned on to keep the status LEDs 20 and 50 lit. However, the present invention is not limited to this, and when the I / O power supply is on,
Whether or not the short circuit detection signal is output from the transistors 16 'and 46' is determined, and when the I / O power supply is turned off, the state immediately before that (presence or absence of the short circuit detection signal) is retained. May be.

That is, when the previous short circuit detection result is stored and the short circuit detection signal is received immediately before the I / O power supply is turned off and the status LEDs 20 and 50 are turned on, It is considered that the short circuit detection signal is received even after the I / O power supply is turned off, and the status LED2
The 0 and 50 are operated so as to keep lighting. In this case as well, the turning off of the status LEDs 20 and 50 can be executed, for example, when the I / O power supply is turned from OFF to ON.

When such a function is incorporated, for example, the O
When performing maintenance processing in the N state,
Although the short-circuit state is resolved without turning off the power, in such a case, the status LED can be turned off together with the short-circuit elimination.

[0060]

As described above, according to the present invention, even if the power supply for the output device is turned off, the alarm means for specifying the output device (OUT terminal) having an abnormality such as a short circuit can be continuously operated. , It is possible to easily identify the target of maintenance.

[Brief description of drawings]

FIG. 1 is a diagram showing a conventional example.

FIG. 2 is a diagram showing a schematic configuration of an internal structure of a conventional slave.

FIG. 3 is a diagram showing a specific configuration of the internal structure.

FIG. 4 is a diagram showing a schematic configuration of an internal structure of a slave which is a preferred embodiment of the present invention.

FIG. 5 is a diagram showing a specific configuration of the internal structure.

FIG. 6 is a flowchart showing the functions of the MPU.

FIG. 7 is a timing chart illustrating the operation of the MPU.

FIG. 8 is a diagram showing an example of a PLC.

FIG. 9 is a diagram showing a specific configuration of the internal structure of an output unit that is a preferred embodiment of the present invention.

[Explanation of symbols]

10 slaves 11 Communication interface 12 Communications Department 13 MPU 14a, 14c flip-flops 14b bus buffer 15a to 15c Photocoupler 16 Output circuit with built-in short circuit detection 16 'transistor 16 "OUT terminal 17 I / O_LED 18 Internal circuit power supply 19 I / O power supply 19 'switch 20 Status LED 25 Output device 30 base 31 Output unit 32 input units 33 CPU unit 34 power supply unit 41 Interface 43 MPU 44a, 44c flip-flops 44b bus buffer 45a-45c Photocoupler 46 Output circuit with built-in short circuit detection 46 'transistor 46 "OUT terminal 47 I / O_LED 49 I / O power supply 49 'switch 50 Status LED 51 Output device

Claims (4)

[Claims] 1. An apparatus for an output device having an output terminal for connecting an output device, comprising: an output circuit for turning on / off the output terminal; and a control means for controlling an operation of the output circuit. While having a circuit, the internal circuit and the output circuit are configured to be supplied with power from respective power supply lines of different systems, and the output circuit outputs an abnormality detection signal to the control unit when an abnormality is detected. When receiving the abnormality detection signal, the control unit outputs an output signal for operating the alarm unit, and also turns on / off the power supply line for the output circuit. Output device equipment characterized by monitoring and continuing the output when the output signal is being output immediately before, even if the power supply line is turned off. Place 2. The output device apparatus according to claim 1, wherein the control means cancels the output of the output signal when the power supply line returns from OFF to ON. . 3. An output device apparatus having an output terminal for connecting an output device, comprising: an output circuit for turning on / off the output terminal; and a control means for controlling the operation of the output circuit. While having a circuit, the internal circuit and the output circuit are configured to be supplied with power from respective power supply lines of different systems, and the output circuit outputs an abnormality detection signal to the control unit when an abnormality is detected. Has a function of outputting, when the control means receives the abnormality detection signal,
Continue to output an output signal for operating the alarm means, and turn on / off the power supply line for the output circuit
An apparatus for output device, which monitors a state and cancels the output of the output signal when the power supply line returns from OFF to ON. 4. The device for output equipment according to claim 1, wherein the device for output equipment is an output unit for constituting a slave or a PLC.