JPH0738978A - Fault display device - Google Patents

Abstract

PURPOSE:To provide the small sized, highly reliable and inexpensive fault display device by employing a photo relay element for the state display device displaying a state of a power generating plant. CONSTITUTION:The display device is made up of a b-contact of a pushbutton for a lamp reset signal use, an a-contact 1b of a pushbutton for an alarm stop signal, a fault detection input contact 2, a b-contact 3a for photo relay, a- contacts 3b-3e for the photo relay, an illumination display device 4, a fault display circuit 5 and an alarm circuit 6, and captions AL, AR, LR, F, P and N indicate respectively an alarm generating signal, a fault stop signal, a lamp set signal, a blink signal, a P-pole of a power supply and an N-pole of the power supply.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a failure display device for monitoring an abnormal state of a plant such as a power plant or a factory, and has a failure display circuit in the case of an illumination display device using a lamp or a light emitting diode as a light source. The present invention relates to an integrated failure display device having a built-in device.

[0002]

2. Description of the Related Art At an electric station such as a power plant or a factory, the state of the plant is constantly monitored, and if an abnormality should occur, it is promptly dealt with to prevent an accident from occurring. A failure display device is provided to monitor abnormalities in each part of the plant.

There are two types of construction methods for the structural form of the failure display device. First, as a first method, multiple (several dozen) failure display circuits are put together in one unit and mounted inside or on the back of the control panel, and a lamp or a light emitting diode for displaying the output of the failure display circuit is used as a light source. The illumination indicator is attached to the front of the control panel (operator's side of operation), and the illumination indicator and the failure display circuit are separated. The second method is one for each illumination indicator. There is an integrated system in which each failure display circuit is configured and the failure display circuit is built in the case of the illumination display, that is, the illumination display and the failure display circuit are integrated. The latter is referred to as an integrated failure display device, and as compared with the former separate type, wiring between the illumination indicator and the failure display circuit is not required as wiring in the control panel, and the number of wiring steps can be reduced. Therefore, the control panel installed in the field has a simple failure display method, so the failure display circuit is configured with an electromagnetic relay type with a simple circuit, and an integrated type with an electromagnetic relay built in the case of the illuminated display. Failure display devices are increasingly used.

[0004]

However, since the conventional electromagnetic relay type has a mechanical part, there is a limit to quality improvement as compared with semiconductor circuits such as contact failure and coil disconnection, and further quality improvement is desired. There is.

Since the front size of the integrated failure display device is determined by the illumination display and the depth size cannot be lengthened due to restrictions in the control panel, it is important that the size is small. At present, in many cases, the electromagnetic relay type (two or less) is used because of its size reduction.

On the other hand, as a method of miniaturization, there is also a method of displaying a failure display device having an electronic circuit structure such as an IC. However, when a large number of circuit elements are mounted on the same printed circuit board, a great effect can be obtained. In the case of the structure, the failure display circuit and the illumination display may be one-to-one, so the circuit is also one circuit. However, in this case, if the power supply circuit and the input / output section are also included, the advantage of downsizing cannot be exerted so much in a circuit such as an IC, and the circuit space is taken up far more than using an electromagnetic relay.
There is a weakness that makes it impossible to pursue further miniaturization.

Therefore, an electronic circuit such as an IC has a large outer shape as a built-in circuit and is not suitable as an integrated failure display device. As described above, a compact and highly reliable integrated failure display device having a semiconductor structure has not yet been realized.

An object of the present invention is to use a photoelectric solid state relay (abbreviated as a photo relay) as an element of a failure display circuit, and to construct a compact, highly reliable and inexpensive integrated type composed of a semiconductor circuit. To realize the failure display device.

[0009]

In order to achieve the above object, the failure display device according to the invention of claim 1 is a failure display device for displaying the status when an abnormality occurs in the power plant. Holding means for holding a signal input to the failure display device for a certain period of time when it occurs, and outputting the input signal while the signal is output from the holding means in parallel with the holding means. 1 photo relay and the first photo relay are connected in series to the output side of the first photo relay, and actuated by a signal output from the holding means,
A second photo relay for inputting a power supply signal and outputting it to the input side of the first photo relay, and the second photo relay.
A third photo relay that is connected in series to the output side of the device and that operates by the signal output from the holding unit; and an alarm output unit that outputs an alarm signal while the signal is output from the first photo relay. An alarm stop means for outputting a signal for stopping the alarm being output by the alarm output means, and the alarm stop means are connected in series, and are activated when a signal from the alarm stop means is input, and further an abnormality occurs. A fourth photo relay for inputting the signal output at the time of occurrence and outputting the signal to the alarm stop means side;
The fifth photo relay which is connected in series to the output side of the photo relay and operates when a signal from the alarm stop means is input and outputs a continuous lighting signal, and the blinking signal and the continuous lighting signal are input. , And display means for displaying according to each signal.

According to a second aspect of the present invention, there is provided the failure display device according to the first aspect, wherein the display means is provided with individual display means corresponding to the blinking signal and the continuous lighting signal. .

According to another aspect of the present invention, there is provided a failure display device for displaying a state of an abnormality in a power plant, wherein a signal input to the failure display device when the abnormality occurs. Holding means for holding a fixed time, a first photo relay connected in parallel with the holding means and outputting an input signal while a signal is output from the holding means, and a first photo relay of the first photo relay The first photo relay is connected in series to the output side and operates by a signal output from the holding means and receives a power supply signal as an input.
A second photo relay that outputs to the input side of the second photo relay and a third photo relay that is connected in series to the output side of the second photo relay and that operates by the signal output from the holding means and outputs a continuous lighting signal. And an alarm output means for outputting an alarm signal while the abnormal signal is input and an alarm stop signal is input, and a display means for inputting and displaying the continuous lighting signal. To do.

[0012]

According to the present invention, a plurality of photo relay elements are combined to form a failure display device, which is smaller than the electromagnetic relay type.
Its function is to generate an alarm pulse from the first photo relay when a failure is input when an abnormality occurs, and the alarm pulse is input to the alarm output means. In addition, the self-holding circuit of the second photo relay operates by the fault input, and the fault occurrence is held. At the same time, the operator is informed by blinking or continuously lighting the display means. Next, the alarm circuit is stopped by the alarm stop signal, and the display means is switched from blinking to continuous lighting. When the fault input has already been recovered, the display means is turned off, and when the fault input is not recovered, the continuous lighting is maintained. or,
As a display method on the display means, the display means is individually provided according to the blinking signal and the continuous lighting signal.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 is a circuit diagram of an embodiment of the failure display device of the present invention. Here, only one element of the failure display device is shown (in reality, a plurality of elements are used). In FIG. 1, 1a is a push-button b contact for a lamp reset signal, 1b is a push-button a contact for an alarm stop signal, 2 is a fault contact for fault detection input, and 3a is a photoelectric solid state relay (abbreviation) : Photo relay- (hereinafter referred to as this) b contact type, 3b to 3e
Is a contact type of photo relay, 4 is an illumination indicator using a lamp or a light emitting diode as a light source, 5 is a failure display circuit, 6 is an alarm circuit, and an alarm pulse from the failure display circuit 5 is input from an alarm generation signal AL. As a result, an alarm output is generated, the output is held, an alarm device (not shown) is sounded, and the alarm is stopped by an alarm stop signal. D _{1 to} D ₇ are diodes, R _{1 to} R ₅ are resistors, C is a capacitor, P and N are P and N poles of the DC power supply, LR is a lamp reset signal busbar, AR is an alarm stop signal busbar, F is a blinking signal bus for blinking the illumination display, which is obtained from a blinking signal generator (flicker relay) not shown, and is always on and off to generate a signal.

AL is an alarm generation signal bus, which is a common signal line from which an alarm pulse is output from each failure display circuit 5. In FIG. 1, only one fault display circuit 5 is shown, but a plurality of circuits (see FIG. 2 usually having several tens of points) are connected between the bus lines and used. One alarm circuit 6 and push buttons 1a and 1b are used in common. The resistors R ₃ and R ₅ are used for shunting the input currents of the photo relays 3a and 3c, and a minute level current bypasses the resistors R ₃ and R ₅ to form a dead zone current. Resistance (R ₁ + R ₂ ) is photo relay-3a-3
The input current limiting resistance of c and the resistance R ₄ are the photo relay 3d,
3e is an input current limiting resistor. The capacitor C is a time-definite capacitor that determines a delay time t ₁ from turning on of the fault contact 2 to operation of the output element of the photo relay 3a.

The contents of the photo relay, which is the main element of the circuit, will now be described with reference to FIG. (A) is a photo relay
Shows the internal circuit of the LED, where LED is a light emitting element,
E is a light receiving element, FET is a MOS field effect transistor, and D is a protection diode. When a direct current flows through the LED, it emits light, and the light receiving element E receives this light, the gate of the next-stage FET is driven, the FET turns on, and the current I
Flows.

Here, the LED and E are optically coupled and insulated. Comparing this photo relay (a) with an electromagnetic relay, the LED corresponds to the coil, the FET corresponds to the output contact, and the FE on the output side is turned on and off by turning the input current of the LED on and off.
T can be turned on and off. That is, it corresponds to the 1a contact type of the electromagnetic relay. (B) is a diagram equivalently expressing the circuit of (A) by a contact, and is a contact diagram because opening and closing of the FET is similar to opening and closing of the contact. After that, photo relay
The element diagram of is expressed by this (b) diagram. Note that FIG. 3 shows a
Although the description has been given with respect to the contact, the same applies to the b-contact output type, and equivalently, a b-contact diagram is used, and these two types are selectively used depending on the circuit.

Next, the failure display operation of this embodiment will be described with reference to the circuit diagram of the failure display device of FIG. 1 and the operation time chart of FIG. In the standby state, the fault contact 2 is off (open), no current flows through the inputs of the photo relays 3a to 3c, and all the outputs of the photo relays 3a to 3c are in a non-operating state.
3a is on, and photo relays 3b and 3c are off. The illumination indicator 4 does not display because the photo relay 3c is off, and the alarm circuit 6 also has a fault contact 2 that is off, so that the diode D ₄ is activated even when the photo relay 3a is on (contact b).
No current flows from the alarm generation signal AL to the alarm circuit 6 and the alarm circuit 6 is also in the off state, and the alarm is generated (display and alarm sound).
There is no. The photo relays 3d and 3e also have no input current and are inoperative. Next, when a failure occurs and the failure contact 2 is turned on, an alarm pulse is first output to the alarm generation signal AL as follows. When the fault contact 2 is turned on, a current flows into the alarm generation signal AL through the diode D ₁ , the contact b of the photo relay 3a, and the diode D ₄ and is input to the alarm circuit 6.
At the same time, a current starts to flow to the inputs of the photo relays 3a to 3c through the diode D ₁ and the resistors (R ₁ and R ₂ ), but it is determined by the time circuit of the capacitor C and the resistors (R ₁ and R ₂ ) connected to the input. The current rise is delayed by the delay time.

Therefore, since the operations of the photo relays 3a to 3c are also slightly delayed, the output of the photo relay 3a is switched from the on-state to the off-state after this delay operation time (t ₁ ) and is flowing to the above-mentioned alarm generation signal AL. The current is cut off. Therefore, the alarm pulse output becomes a pulse current only at the moment of the delay operation time (t ₁ ) of the photo relay 3a.

In response to this alarm pulse, the alarm circuit 6 operates and sounds an alarm (for example, a bell), and holds the output until the alarm stop signal AR is input. Next, since the output of the illuminated indicator 4 is turned on by the operation of the photo relay 3c described above, a blinking signal is supplied from the blinking signal bus F and the illuminated indicator 4 blinks (flicker).

Next, the self-holding operation of the photo relay 3b will be described. In order to keep the failure occurrence even if the failure contact 2 is turned off in a short time, at the same time as the operation of the photo relays 3a to 3c, from the lamp reset signal bus LR to the diode D ₂ and from the a contact of the photo relay 3b, Resistance (R ₁ and R
_A current is caused to flow to the inputs of the photo relays 3a to 3c through ₂ ) to maintain the operation of the photo relays 3a to 3c. In this fault occurrence state, the photo relay (3
Since the push button 1b (for alarm stop) is not operated on the (d, 3e) side, no input current flows and no operation occurs. The operation up to the occurrence of this failure is shown in the time charts a to d of FIG. Next, when the operator confirms that a failure has occurred, the alarm stop push button 1b is pressed to cancel the failure occurrence state.

Then, from alarm stop bus bar AR to diode D
₅ , a current flows through the inputs of the photo relays 3d and 3e through the resistor R ₄ , and the photo relays 3d and 3e operate. At the same time that the photo relay 3d operates, the photo relay 3d,
For input of 3e, power supply P → push button 1a → diode D ₂
→ Photo relay 3b a-contact → Photo relay 3d a-contact → via diode D ₆ to photo relays 3d, 3
Since an input current flows through e, the photo relays 3d and 3e hold themselves even if the alarm stop push button 1b is released. At the same time, the illumination indicator 4 is operated from the lamp reset signal bus LR to the diode D by the operation of the photo relay 3e.
_A continuous lighting current is supplied through ₇ , and the lighting state is set.
As for the alarm, the alarm stop signal AR enters the alarm circuit 6 by the operation of the push button 1b and the alarm is stopped. Next, when the fault contact 2 is turned off, since the photo relay 3b and the photo relay 3d are in the self-holding state, there is no change in the circuit operation and the display remains lit. After that, when the lamp reset push button 1a is pressed, the current for self-holding of the photo relay 3b and the photo relay 3d is cut off, so the self holding is released and all the photo relays 3a to 3e are turned off, and the standby before the failure occurs. Return to the state. The above operation is shown in the time chart of FIG.
In addition, at the time of lamp reset, if the fault contact 2 is not recovered and is still ON, the lamp reset signal LR causes P
Even when the current I _L from the power supply is cut off, Fotorire -3a~
Since the input currents of 3c and the photo relays 3d and 3e are supplied from the fault contact 2, the operation does not change, and the illumination indicator 4 maintains the previous continuous lighting state, indicating that the fault is not recovered. To do.

As described above, the failure display function can be realized with a simple circuit. In addition, the photo relay has an external shape that is as small as an IC, so no circuit space is required and the operating voltage is up to DC 400 ^v.
It has the advantage of being a circuit that can be used in the same way and can be directly driven even when it is used for the control power supply DC110 ^v of a power plant or the like.

FIG. 5 shows a circuit diagram of a failure display device according to another embodiment. Here, the symbols of the respective parts are the same as those in FIG. In the circuit diagram of the failure display device of FIG. 5, the circuits of the photo relays 3d and 3e are excluded from the circuit diagram of FIG. 1, the node of the diode D ₃ on the output side of the photo relay 3c is turned off, and the signal F is stopped. The circuit is further simplified by connecting to the P pole of a DC power source and changing the illumination display 4 so that it continuously lights up when a failure occurs. Therefore, since the failure display operation is almost similar to that of FIG. 1, the operation of this embodiment will be briefly described.

First, in a standby state in which no failure occurs, the failure contact 2 is off, so that no current flows into the inputs of the photo relays 3a to 3c, the photo relays 3a to 3c do not operate, and neither a display nor an alarm is issued.

Next, when a failure occurs and the failure contact 2 is turned on, the alarm pulse is output to the alarm generation signal AL for the time t ₁ with the same content as described in FIG. 1, and the alarm circuit 6 operates. The alarm is sounded and the output is held until the alarm stop push button 1b is operated. At the same time, the illumination display 4 is continuously turned on by the operation of the photo relay 3c through the contact a of power P → diode D ₃ → photo relay 3c output. The self-holding operation of the photo relay 3b is exactly the same as that described with reference to FIG.
At the same time as the operation of the photo relays 3a to 3c, a current flows to the inputs of the photo relays 3a to 3c via the power source P → push button 1a → diode D ₂ → the output of the photo relay 3b. Even so, the photo relays 3a to 3c hold themselves. Next, when the alarm stop push button 1b is pressed, the alarm circuit 6 is reset and the alarm stops. In this case, the illumination indicator 4 does not change its operation and remains lit continuously.
Next, when the fault contact 2 is turned off, the photo relays 3a to 3c are self-holding, the operation is not changed, and the illumination display 4 is also continuously lit.

After that, the lamp reset push button 1b
When (LR) is pressed, the fault contact 2 is turned off, so the self-holding of the photo relay 3b is released and the photo relay 3 is released.
The a to 3c are in the inoperative state, and return to the state before the occurrence of the original failure. The illumination display 4 is also turned off by turning off the photo relay 3c. If the defective contact 2 is not recovered and is in the ON state at the time of lamp resetting, the self-holding of the photo relay 3b is not released and the illumination display 4 continues to be in the continuously lit state. As described above, the circuit of FIG. 1 can be changed to the circuit of FIG. 5 and used as a simple failure display operation.

[0027]

When the fault display circuit and the illumination indicator are integrally formed, it is necessary to reduce the size due to the restrictions on the mounting of the control panel. Therefore, an integrated fault display device using a small electromagnetic relay is required. It was the conventional method. However, there is a difficulty in improving the quality because of the existence of the mechanical part. By using the circuit of the present invention, it is possible to realize an all-in-one failure display device having a semiconductor circuit configuration in a smaller size than conventional ones, and to expect remarkably high reliability in terms of quality. In addition, the same as the conventional electromagnetic relay, D
The C110 ^v also works directly and the circuit is simple, so an inexpensive one can be obtained. In particular, the optimum one can be obtained as an integrated failure indicator for field control panels.

[Brief description of drawings]

FIG. 1 is a circuit configuration diagram of a failure display device according to an embodiment.

FIG. 2 is an overall configuration diagram of a failure display device according to the present embodiment.

FIG. 3 is a configuration diagram of a photo relay according to the present embodiment.

FIG. 4 is an operation chart of the present embodiment.

FIG. 5 is a circuit configuration diagram of a failure display device according to a second embodiment.

[Explanation of symbols]

1a, 1b ... push button, 2 ... fault contact, 3a ... a contact photo relay, 3b, 3c, 3d, 3e ... b contact photo relay, 4 ... illumination indicator, 5 ... circuit diagram, 6 ... alarm circuit, D ... diode, R ... resistor

Claims (3)

[Claims] 1. A failure display device for displaying the state of an abnormality occurring in a power plant, and a holding means for holding a signal input to the failure display device for a certain period of time when the abnormality occurs; A first photo relay that outputs an input signal while the signal is output from the holding device in parallel with the holding device, and the first photo relay is connected in series to the output side of the first photo relay, and the holding device is provided. A second one which operates by a signal output from the first photo relay and which receives a power supply signal and outputs it to the input side of the first photo relay;
And a third photo relay connected in series to the output side of the second photo relay and operated by a signal output from the holding means, and a signal is output from the first photo relay. while,
An alarm output unit that outputs an alarm signal, an alarm stop unit that outputs a signal that stops the alarm output by the alarm output unit, and a signal from the alarm stop unit that is connected in series with the alarm stop unit. It operates when input, and further inputs the signal output when an abnormality occurs and is connected in series to a fourth photo relay which outputs to the alarm stop means side and an output side of the fourth photo relay. , A fifth photo relay that is activated when a signal from the alarm stop means is input and outputs a continuous lighting signal, and the blinking signal and the continuous lighting signal are input, and display is performed according to each signal. A failure display device comprising means. 2. The failure display device according to claim 2, further comprising an individual display unit according to the blinking signal and the continuous lighting signal. 3. A failure display device for displaying the state of an abnormality occurring in a power plant, and holding means for holding a signal input to the failure display device for a certain period of time when the abnormality occurs, A first connection means connected in parallel with the holding means and outputting the input signal while the holding means outputs the signal;
And a second photo-relay connected in series to the output side of the first photo-relay and operated by a signal output from the holding means to input a power supply signal and output to the input side of the first photo-relay.
And a third photo relay that is connected in series to the output side of the second photo relay and that operates by a signal output from the holding means and outputs a continuous lighting signal, and the abnormal signal is input. A failure display device comprising: an alarm output means for outputting an alarm signal while an alarm stop signal is input; and a display means for inputting the continuous lighting signal and displaying.