JP3155623B2 - Gas fire extinguishing equipment with ground fault detection circuit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas fire extinguishing system for extinguishing a fire by using a gas fire extinguishing agent, and more particularly to a ground fault detecting device capable of detecting a ground fault in an electric circuit used in the circuit. The present invention relates to a gas fire extinguishing system equipped with a circuit.

[0002]

2. Description of the Related Art Gas fire extinguishing systems for extinguishing fires using carbon dioxide, halon, etc. as a fire extinguishing agent today include parking lots, electrical equipment rooms, computer rooms, communication equipment installation rooms,
It is installed in many places such as dangerous goods facilities. The gas fire extinguishing system generally includes an operation box which is arranged for each of a plurality of fire prevention sections and includes an operation circuit, and a control panel including a control circuit to which each operation circuit is connected.

The operating circuit includes a starting circuit. When a fire occurs, the starting circuit is operated by a switch operation of a person in the fire prevention section, and a signal is transmitted from the operating circuit to the control circuit. Based on this signal, the control circuit issues commands such as generation of a fire alarm for evacuation of personnel, operation of a timer, and release of gas to the fire prevention section after a predetermined time has elapsed, thereby extinguishing the fire. A signaling signal indicating these states is transmitted to the central monitoring panel.

When the fire extinguishing system is started automatically, a fire detection signal from a fire detector is input to a control circuit, and a gas release command is sent out.

[0005]

While such a gas fire extinguishing system is required to operate quickly in the event of a fire, it is desirable to prevent fire extinguishing agent from being released due to malfunction. It is. In particular, when carbon dioxide is used as a fire extinguishing agent, there is a danger of damaging the human body, such as suffocation of people present at the site. Is coming.

As one of the demands, it is desired to display an electric circuit between the operation box and the control panel, a power supply line, and a start circuit in the operation box when a ground fault occurs. As another requirement, it is desired to prevent a malfunction caused by a short circuit of a start circuit. The present invention has been made in view of such a demand, and has as its object to provide a gas fire extinguishing system including a ground fault detection circuit.

It is another object of the present invention to provide a gas fire extinguishing system which can detect a ground fault in each fire extinguishing section in a fire extinguishing apparatus provided with an operation box for each of a plurality of fire preventing sections. Still another object of the present invention is to provide a gas fire extinguishing system capable of distinguishing between a short circuit and a ground fault in a starting circuit.

[0008]

In order to achieve the above object, a gas fire extinguishing system equipped with a ground fault detecting circuit according to the present invention comprises: an operating circuit including a starting circuit provided in a fire protection compartment;
A fraction control circuit connected to the operation circuit;
Power supply circuit for supplying different voltages to two power supply lines
When a start signal from the start circuit is supplied to the fraction control circuit via the start electric circuit, a command for releasing the gas-based fire extinguishing agent from the fraction control circuit to the fire protection compartment is transmitted. In a gas-based fire extinguishing system, a ground fault monitor is installed between the fractionation control circuit and the operation circuit to monitor the ground fault.
An electrical path to the operating circuit or fractionated control fractions connecting lines through the element Ru is connected to the power supply line of the high voltage in the circuit view provided to the control circuit, further between the ground point and the two power lines So
Each has a neutral circuit connected via a resistor,
Further, a power supply line having a low voltage at one end is provided to the fraction control circuit.
Connected to detect the other end and a resistor connecting voltage detection and the fraction connecting line, a voltage change occurring in the other end of the voltage detecting resistor, the ground絡監view path by a change of the voltage And a circuit for detecting occurrence of a ground fault.

Further, with respect to the plurality of fire sections, the operation circuit is provided for each of a plurality of <br/> firestop, to the control circuit,
Each of the operation circuits is provided with a corresponding fraction control circuit, and the occurrence of a ground fault in the ground fault monitoring electric circuit can be detected for each fire protection section. Further, the two power supply lines are connected via two resistors, and the control circuit further includes a connection between the two resistors.
A power line ground fault detection circuit that detects a voltage difference between a connection point and the ground point of the neutral circuit, and detects a ground fault occurrence of a high voltage power line based on a change in the voltage difference. It is good to have.

[0010] In order to perform both of the ground fault and short-circuit detection, the
A starting circuit is provided between the fractionation control circuit and the starting circuit,
At the time of start-up, the high voltage power supply line and the
The connection signal is conducted to the image connection line, and the start signal is transmitted to the fraction control circuit.
So that, when not activated, the activation circuit is
When short-circuited with a high-voltage power supply line , the ground fault detection circuit detects the occurrence of a short-circuit from the amount of change in the voltage generated at the other end of the voltage detection resistor, and differs from the occurrence of a ground fault. You can also judge.

[0011]

When the ground fault monitoring circuit is grounded, a ground current flows between the ground point of the neutral circuit and the ground fault point, and this current flows through the voltage detecting resistor through the dividing connection line. Therefore, the voltage generated by the voltage detecting resistor changes more than normal. By detecting this change, the occurrence of a ground fault can be detected.

Further, the potential of the ground point of the neutral circuit, the relationship between the potential of the connection point that is not grounded generated by the resistor connected to the power supply line in parallel with the neutral circuit, the power supply line in a normal state and a high voltage It changes with the time of the ground fault. By detecting this change, it is possible to detect that a ground fault has occurred in the high-voltage power supply line. Furthermore, if the start-up circuit and the high-voltage power supply line are short-circuited and the operation circuit is not started up, but the start-up signal flows, the current passes through the fractional connection line to form a voltage detection resistor. Flows. Therefore, the voltage generated by the voltage detecting resistor shows a change different from that in the case of the ground fault, and the occurrence of the short circuit can be detected by determining the change.

[0013]

An embodiment according to the present invention will be described with reference to the drawings. FIG. 1 is a schematic overall view of the present embodiment, and FIG. 2 is a detailed circuit diagram of a main part thereof. In the figure, reference numeral 1 denotes a control circuit installed in a control panel, and reference numerals 5, 5,... Denote operation circuits installed in operation boxes arranged for each fire prevention section.

A control circuit 1 rectifies an AC voltage and outputs voltages + B, -B and + E, a power supply circuit 2, and fraction control circuits 3, 3,. A neutral circuit 6 and a + B ground fault detection circuit 7 are provided. Each fraction control circuit 3 responds to a signal from the operation circuit 5 or a fire detection signal from the fire detector,
This is a circuit for outputting various operation signals such as a door closing signal and a fire extinguishing agent discharge signal, and supplying a transfer signal indicating these states to a central monitoring panel to display the signal to a monitoring person. Further, each of the fraction control circuits 3 includes a ground fault detection circuit 4 connected to the operation circuit 5 via the fraction connection line L3, and detects a ground fault for each fire protection section together with the neutral circuit 6. . The + B ground fault detection circuit 7 is a circuit for detecting a ground fault of the + B power supply line.

FIG. 2 is a detailed circuit diagram of the main part of the fraction control circuit 3 including the neutral circuit 6, the + B ground fault detecting circuit 7, and the ground fault detecting circuit 4 and the main part of the operation circuit 5. 2, the electric circuit L1 is a + B power line from the power circuit 2, and the electric circuit L2 is a -B power line from the power circuit 2. The resistors R1 and R2 for connecting the + B power line L1 and the -B power line L2 to the ground point are resistors for forming a ground point, and have the same resistance value. Has become. A neutral circuit 6 is formed by the resistors R1 and R2.

Similarly, resistors R3 and R4 connected in series between + B power supply line L1 and -B power supply line L2 are R1 and R2.
Cooperates with a resistor for detecting a ground fault of a power supply line, which will be described later, so that a potential at a connection point between the resistors R3 and R4 is higher than a potential at a connection point between the resistors R1 and R2 in a normal state. Is set to the magnitude of the resistance value. Resistance R1
The connection point of the comparator C1 and the connection point of the resistor R3 and the connection point of the resistors R3 and R4 are input to the + terminal and the − terminal of the comparator C1, respectively.
Is supplied to an OR circuit OR1. This resistance R
3, R4 and the comparator C1 form a + B ground fault detection circuit 7.

Next, R7 in the fractionation control circuit 3 is used for detecting a ground fault in the electric circuit between the fractionation control circuit 3 and the operation circuit 5 and a voltage detection for detecting a ground fault in the operation circuit 5. Resistance
One end is connected to the -B power supply line L2, and the other end is connected to the fractional connection line L3.
And comparators C2 and C3. The comparator C2 is a ground fault upper limit comparator, and outputs a voltage V1 as an upper limit setting voltage divided by a variable resistor R5 connected between the constant voltage E and the -B power supply line L2 and a voltage generated in the resistor R7. Compare. Similarly, the comparator C3 is a ground fault lower limit comparator, and the constant voltage E and -B
The voltage V2, which is the lower limit setting voltage divided by the variable resistor R6 connected to the power supply line L2, is compared with the voltage generated at the resistor R7. The comparators C2 and C3 are AND circuits A
A window comparator is formed together with ND1, and a resistor R7
AND voltage when the voltage V1>V> V2 satisfies the relationship V1>V> V2
A signal is output from the circuit AND1 and supplied to the OR circuit OR1.

The output terminal of the OR circuit OR1 is connected to the input terminal of the open collector OC1.
Is connected to the cathode end of the light emitting diode D1. Therefore, when the signal from the OR circuit OR1 is input to the open collector OC1, the light emitting diode D1 is turned on. The light emitting diode D1 serves as a ground fault detecting display as described later.

The operation circuit 5 is also supplied with the + B power supply line L1 from the control circuit 1 and also introduces a fractional connection line L3 connected to the resistor R7. The switch S0, one end of which is connected to the + B power supply line L1, is a switch that closes when the front door of the operation box is opened, and the other end passes through the electric circuit L4 and connects the diodes and the relays K5, K6 in the fraction control circuit 3. Through the connection line L3. The relays K5 and K6 are used to execute a fire extinguishing preparation work, and specifically function as switches for activating an alarm generation circuit (not shown).

The switch S1, which can be operated only after the door of the operation box is opened, is a start switch for fire extinguishing work. One end of the switch S1 is connected to the + B power supply line L1, and the other end is connected to the dividing connection line via the relay K0. Connected to L3. When the relay K0 is operated, the contacts 0-1 of the operation circuit are switched.
The relay K0 and the contacts 0-1 form an activation circuit.

The contact 0-1 connects the + B power supply line L1 to the photocoupler P1 of the division control circuit 3 through the electric circuit L6 when the relay K0 is in the non-operation state.
Is turned on. Therefore, the relay K1 having one end connected to the + B power supply line L1 in the fraction control circuit 3 and the other end connected to the transistor of the photocoupler P1 is connected to a relay.
When K0 is in the non-operation state, it is energized and in the operation state.
On the other hand, when the relay K0 is operated, the contact 0-1 connects the + B power supply line L1 to the contact 1-1 of the fraction control circuit 3 through the electric circuit L5. The contact 1-1 opens when the relay K1 is activated, and closes when the relay K1 is not activated. Relays K2, K3, and K4 are connected in parallel from the other end of the contact 1-1. Each of the relays K2, K3, and K4 is for executing the next operation for extinguishing the fire. Specifically, a timer (not shown) is activated to create a delay time and give grace for evacuation of personnel. It functions as a switch for sequentially operating relays for each operation such as closing the next door and discharging the fire extinguishing agent. The other ends of the relays K2, K3, K4 are connected to the fractional connection line L3 via the contacts 6-2. Contact 6-2 is relay K6
Of the relay K2, K
3, K4 can be activated when the contacts 0-1, 1-1 and 6-2 are all closed.

The electric circuit L5 from the contacts 0-1 is also connected to the dividing connection line L3 via the contact 2-1 and the relay K7 in the dividing control circuit 3. The contact 2-1 is connected to the relay K
Opened by activation of 2. The electric path passing through the contact 2-1 and the relay K7 is for detecting a short circuit of the starting circuit. The contact 6-1 which is closed by the operation of the relay K6 is also connected in parallel with the resistor R7.

The operation circuit 5 further has a plurality of indicator lights D3, D4, D5 and D6 each composed of a light emitting diode. The diode D3 is a power-on indicator lamp for connecting the + B power supply line L1 and the division connection line L3. The diodes D4, D5, and D6 are a start indicator, a fire extinguisher discharge indicator, and a valve closing indicator, respectively.
8, L8, contacts 8-1, 9-1,
The other end is connected to the power supply line L1, and the other end is connected to the fractional connection line L3. Each diode is turned on by closing each of the contacts 8-1, 9-1 and 10-1 when the respective work is performed.

Further, the fraction control circuit 3 is provided with a short-circuit display diode D2, the cathode terminal of which is connected to the output terminal of the open collector OC2.
The input terminal of C2 is connected to contact 7-1. The contact 7-1 is closed by the operation of the relay K7 and the light emitting diode D2
Is configured to light up. In the fractionation control circuit 3 configured as described above, the ground fault detection circuit 4 mainly includes resistors R1, R2, R3, R4, a voltage detection resistor R7, and comparators C1, C2, C3.

The operation of this embodiment will be described below. When the fire extinguishing system according to the present embodiment is not operated and is in a normal state where neither a ground fault nor a short circuit occurs, the light emitting diode D3
, And an electric circuit formed by the contacts 0-1 from the + B power supply line L1 through the electric circuit L6 to the fractional connection line L3. Therefore, the resistance R
7, the voltage flowing through these circuits (I
1, I2).

On the other hand, consider a case where any one of the electric circuits L4 to L9 between the fraction control circuit 3 and the operation circuit 5 and any one of the electric circuits in the operation circuit 5 are grounded. All the electrical paths are each element , namely relays K5, K6, K7, resistors,
Since it is always connected to the fractional connection line L3 via the photocoupler P1, diodes D4, D5, D6, etc. , the ground point of the neutral circuit 6 is connected to the ground fault point, and an electric circuit passing through the resistor R7 is newly formed. Therefore, more current than the normal state passes through the resistor R7. As a result, the potential of the resistor R7 on the comparator C3 side (point A in FIG. 2) becomes higher than the normal state (V> V2), the change is detected by the comparator C3, and the output is output to the AND circuit AND1. .
Incidentally, the lower limit setting voltage V2 of the comparator C3 by the variable resistor R6.
Is set in advance so as to be slightly higher than the voltage at the point A of the resistor R7 in a normal state and lower than the voltage at the point A of the resistor R7 when a ground fault occurs. Further, an upper limit setting voltage V1 described later is a resistor R7 generated due to these ground faults.
Is set to be higher than the potential at point A. Therefore, a signal is output from the AND circuit AND1 to the OR circuit OR1.

Next, when the + B voltage power supply line is grounded, the relationship between the potential at the connection point between the resistors R1 and R2 and the potential at the connection point between the resistors R3 and R4 changes. For example, the + B voltage is changed to +24
V, -B voltage is 0 V, R1 = 20 kΩ, R2 = 20
When kΩ and R3 = 9 kΩ and R4 = 15 kΩ,
The potential of each connection point is +12 V when viewed from the -B voltage power supply line.
In the normal state, the potential at the connection point between R1 and R2 is smaller than the potential at the connection point between R3 and R4, and no signal is output from the comparator C1. On the other hand, when the + B voltage power supply line is grounded, the magnitude relationship between the potentials at the respective connection points is reversed, and a signal is output from the comparator C1 and supplied to the OR circuit OR1.

As described above, when a ground fault occurs at any point, a signal is input to the OR circuit OR1, the level of the open collector OC1 becomes low, and a current flows through the light emitting diode D1 to emit light, thereby generating a ground fault. Show what you did. Next, a case is considered where the electric circuit L5 serving as a start line is short-circuited to the + B power supply line L1 without switching the contacts 0-1. In this case, since the electric circuit connected to the dividing connection line L3 through the electric circuit L6 is formed as it is, the photocoupler P1 remains ON, and the relay K1 is in the operating state. Therefore, the contact 1-1 remains open and the electric circuit L5
Are short-circuited, the relays K2, K3, K4 do not operate, and no malfunction occurs. Instead, contact 2-
Since 1 is closed, the current I flowing through the relay K7
3 will pass through resistor R7. As a result, the potential at the point A of the resistor R7 is further increased, and the change is detected by the comparator C2. That is, the comparator C using the variable resistor R5
The upper limit setting voltage V1 of 2 is set in advance so as to be slightly smaller than the voltage at the point A of the resistor R7 when the short-circuit current I3 flows, and higher than the voltage at the point A of the resistor R7 in a normal state. Therefore, when a short circuit occurs, V> V1, and the AND circuit AND1 does not output a signal, and as a result, the ground fault indicating diode D1 does not light. Instead, relay K
7, the contact 7-1 is closed, the open collector OC2 goes low, and the light emitting diode D
2 emits light, indicating that a short circuit has occurred.

When a fire occurs and the operation box is operated when the gas fire extinguishing system is in a normal state, that is, when the door of the operation box is opened, the switch S0 is closed to activate the relay K6. Then, the contact 6-1 closes and the voltage of the resistor R7 drops to approximately -B. Therefore, the comparators C2 and C3 do not change their outputs and do not erroneously display a ground fault signal.

As described above, the voltage generated at the point A of the voltage detecting resistor R7 in the normal state and the voltage generated at the point A of the voltage detecting resistor R7 in the abnormal state are distinguished from each other to provide accurate information. Can be displayed. The reason that the current I1 flowing through the light-emitting diode of the photocoupler P1 is used instead of directly using the current flowing through the relay K1 in the operating state as the current flowing through the resistor R7 in the normal state is the normal state. This is because a stable current is supplied to the resistor R7 and the voltage at the point A of the resistor R7 is stabilized without being affected by the current instability due to the impedance change of the coil of the relay K1 to be excited.

[0031]

As described above, according to the present invention,
Monitors ground faults provided between the fractionation control circuit and the operation circuit
In the operation circuit or the fraction control circuit on the ground fault monitoring circuit to be
Fractions connection line provided connected through the elements Ru, the control circuit
In, between more and the ground point and the power supply line of the two different voltages
A neutral circuit that is connected to each other via a resistor, and further includes a voltage control unit that has one end connected to the low-voltage power supply line and the other end connected to the fractionation connection line. a detection resistor, a variation of the voltage detected generated in the other end of the voltage detecting resistor, and a circuit for detecting the land絡発production of the land絡監view path by a change of the voltage, a ground fault detection circuit consisting of With the provision, it is possible to reliably detect the ground fault of the ground fault monitoring electric circuit.

Further, the two power supply lines are connected via two resistors.
And the control circuit further comprises the two resistors
A connecting point between, and detects the difference in voltage between the ground point of the neutral circuit, high voltage by change in the difference of the voltage
By the provided power line ground fault detection circuit for detecting the land絡発raw power line can Karamo reliably detect earth in the power supply line.

Further, the fraction control circuit and the starting circuit
And a starting electric circuit is provided between the starting electric circuit and the starting electric circuit.
The high-voltage power supply line and the fractional connection line conduct and the start-up occurs.
The motion signal is supplied to the fraction control circuit, and the
Sometimes, the starting circuit is short-circuited with the high voltage power line.
And detecting the occurrence of a short circuit from the amount of change in the voltage generated at the other end of the voltage detection resistor when the ground fault detection circuit
The can detect short-circuiting between the power supply line of the start electric path and the high voltage and can prevent malfunction by this.

[Brief description of the drawings]

FIG. 1 is a schematic block diagram of an embodiment of a gas fire extinguishing system according to the present invention.

FIG. 2 is a detailed circuit diagram of a main part of the embodiment of FIG.

[Explanation of symbols]

 Reference Signs List 1 control circuit 2 power supply circuit 3 fractionation control circuit 4 ground fault detection circuit 5 operation circuit 6 neutral circuit 7 power supply line ground fault detection circuit (+ B ground fault detection circuit) L1 positive voltage power line L2 negative voltage power line L3 fraction connection Line R7 Voltage detection resistor

Claims (4)

(57) [Claims] An operation circuit (5) including a starting circuit provided in a fire protection section, and a fraction control circuit (3) connected to the operation circuit (5), and two power lines (L1, L).
And a control circuit (1) including a power supply circuit (2) for supplying different voltages to the power supply circuit (2), and a start signal from the start circuit is supplied to the fractionation control circuit (3) via a start electric circuit (L5).
When supplied to the fire extinguishing system, the fraction control circuit (3) sends a command to release the gas fire extinguishing agent to the fire protection section. A ground fault monitoring circuit (L4, L5, L6,
L7, L8, L9) via a high-voltage power supply line (L1) via elements in the operation circuit (5) or the fractionation control circuit (3).
And the control circuit (1) further includes the two power supply lines (L1, L2).
2) and a neutral circuit (6) connecting the grounding point via resistors (R1, R2), respectively. Further, the fraction control circuit (3) further includes a power supply line (L2) having a low voltage at one end. ), And the other end is connected to the fraction connection line (L
3) and a voltage change occurring at the other end of the voltage detection resistor (R7) connected to the ground detection monitoring circuit (L4, L4).
L5, L6, L7, L8, L9) and a circuit for detecting the occurrence of a ground fault. 2. The gas fire extinguishing system according to claim 1, wherein the operation circuit is provided for each of a plurality of fire protection sections, and the control circuit is provided with a portion corresponding to each operation circuit. Image control circuits (3), and a ground fault monitoring circuit (L
(4, L5, L6, L7, L8, L9) detection of occurrence of ground fault for each fire protection section. 3. The gas fire extinguishing system according to claim 1, wherein the two power lines (L1, L2) are connected via two resistors (R3, R4), and the control circuit (1).
Further detects a voltage difference between a connection point between the two resistors (R3, R4) and the ground point of the neutral circuit (6), and detects a high-voltage power supply line ( A gas fire extinguishing system comprising a power line ground fault detecting circuit (7) for detecting occurrence of a ground fault of L1). 4. The gas fire extinguishing system according to claim 1, wherein a starting electric circuit (L5) is provided between the fraction control circuit (3) and the starting circuit, and the starting electric circuit is provided at the time of starting. The high-voltage power supply line (L1) and the fraction connection line (L3) are conducted through the activation circuit (L5) so that the activation signal is supplied to the fraction control circuit (3); When the starting electric circuit (L5) is short-circuited with the high-voltage power supply line (L1) during non-startup, the ground fault detection circuit (4)
Detects the occurrence of a short circuit from the amount of change in the voltage generated at the other end of the voltage detection resistor (R7), and determines that the occurrence of the short circuit is different from the occurrence of a ground fault.