JPH0562397B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a test circuit for inspecting a fire alarm.

[Background technology]

Fire alarms are usually equipped with a test circuit as shown in Figure 3a. In the same figure, A ₁ , A ₂ , and A ₃ are detection circuits that operate by detecting the line short circuit signal from the fire detector, and in this example, when each detection circuit is activated, the built-in relay activates the sub-receiver B. The relay contacts a ₁ , a ₂ , and a ₃ are activated to light up the indicator lamp. When checking the operation of the fire alarm, turn on the test switch Sw and switch the rotary switch RS in sequence.
The operation of all detection circuits was checked, but in models with a large number of lines, operating this rotary switch was extremely troublesome. In addition, some small fire alarm systems with only a few lines use a test switch Sw to check the operation of all lines at the same time, as shown in Figure b. The disadvantage is that it is not obvious even if the order is changed.

[Purpose of the invention]

The present invention has been made in view of the above problems, and its purpose is to provide a fire alarm test circuit that can sequentially check the operation of all detection circuits with a single switch operation. There is a particular thing.

[Disclosure of the invention]

The fire alarm test circuit of the present invention uses a plurality of detection circuits to supply power to a fire detector installed outside through each signal line, and when the fire detector detects a fire, A short circuit signal of the signal line caused by the operation of the detection circuit turns on the district light installed in the fire alarm body, and also sends a transfer signal to the sub-receiver to display the location of the fire and activate the disaster prevention device. A fire alarm that performs control operations, in which the signal from the sensor is connected to the signal input terminal of the first-stage detection circuit, and the signal from the sensor is connected to one end of a test switch via a diode. The signal output end of the first-stage detection circuit is connected to one end of the test switch via the relay contact of the first-stage delay relay, and the signal output end of the first-stage detection circuit is connected to the first-stage delay relay. Connected to the other end of the test switch through a series circuit between the delay relay and the first-stage district light, and connected to the transfer terminal of the sub-receiver through another relay contact of the first-stage delay relay. When the sensor is activated, the first-stage delay relay is activated to turn on the first-stage district light, and the relay contact of the first-stage delay relay is closed to activate the next-stage detection circuit. The district light is turned on, and at the same time, the sub-receiver is activated by closing the other relay contacts of the delay relay, and in the same way, all the detection circuits are activated in sequence.

FIG. 1 shows an embodiment of the circuit of the present invention. In the figure, detection circuits A ₁ , A ₂ , and A ₃ each supply power supply current to the fire detector through signal lines, and when each fire detector detects a fire, it short-circuits the signal line to detect the fire. Alert the alarm. The detection circuits A ₁ , A ₂ , and A ₃ operate by detecting this line short circuit signal, and turn on the district lights L ₁ , L ₂ , and L ₃ installed in the fire alarm body, or turn on the sub-reception lights. It sends a transfer signal to machine B to display the location of the fire and control disaster prevention equipment. The signal input terminals of these detection circuits A ₁ , A ₂ , A ₃ ... are connected to one test switch Sw via diodes D ₁ , D ₂ , D ₃ ... and relay contacts r ₁ , r ₂ ..., respectively. The relay contacts _{r 1} , r _{2 ,} etc., which are sequentially _inserted into _the adjacent line, _are It's starting to work. R is a current limiting resistor. Note 1
Only the diode _D1 is connected to the input terminal of the th line, that is, the detection circuit _A1 , and no relay contact is connected.

FIG. 2 is a time chart showing the operation of the circuit of the present invention. Test switch now at t ₀
When Sw is turned on, the input terminal of the detection circuit A ₁ is short-circuited by the diode D ₁ and the current limiting resistor R, and the detection circuit A ₁ operates and a detection signal is output to its output terminal. Ru. As a result, delay relay R ₁ operates at time t ₁ with a delay of a certain time T,
The district light _L1 is turned on and a transfer signal is sent to the sub-receiver B to activate the relay contact _a1 , and at the same time, the relay contact _r1 of the adjacent line is turned on. When this relay contact _r1 is turned on, the second detection circuit
A test signal is input to _A2 , and the output of the detection circuit _A2 turns on the district light _L2 at time t2, which is a further T _time later, and activates the relay contact _A2 .

In this way, all the detection circuits A ₁ , A ₂ , A ₃ operate sequentially and in a chain, thereby controlling the district lights L ₁ , L ₂ , L ₃ or the delay relays R ₁ , R ₂ , R ₃ . By the operation of indicator lights or buzzers (not shown) connected to the transfer terminals s ₁ , s ₂ , s ₃ of the sub-receiver B via relay contacts a ₁ , a ₂ , a ₃ , respectively, The operation of each detection circuit is confirmed.

〔Effect of the invention〕

As described above, the present invention not only allows the operating state of a plurality of detection circuits to be sequentially confirmed by turning on the test switch, but also allows the test switch to be connected to the output end of the detection circuit via a delay relay. The lighting state of each district light and the operating state of each indicator light or buzzer connected to the transfer terminal of the sub-receiver through the other relay contact of the delay relay can be checked in correspondence with each other; Tests can be performed efficiently during trial operation and maintenance of fire alarms, and each delay relay has the function of closing the detection circuit of the next stage and the function of conducting the transfer terminal of the sub-receiver. By using the same function, the circuit configuration can be simplified and maintenance and inspection of the circuit can be easily performed.

[Brief explanation of drawings]

FIG. 1 is a block circuit diagram showing one embodiment of the present invention, and FIG. 2 is a time chart showing the operation of the same.
In FIG. 3, a and b are block circuit diagrams showing a conventional example. A ₁ , A ₂ , A ₃ are detection circuits, D ₁ , D ₂ , D ₃ are diodes, L ₁ , L ₂ , L ₃ are district lights, R ₁ , R ₂ , R ₃ are delay relays, A ₁ , a ₂ , a ₃ and r ₁ , r ₂ , r ₃ are the contacts of the delay relay, Sw is the test switch, R is the current limiting resistor, and B is the sub-receiver.

Claims (1)

[Claims] 1 A plurality of detection circuits supply power to a fire detector installed outside through their respective signal lines, and when the fire detector detects a fire, the signal line is activated by the operation of the detection circuits. A fire alarm that uses a short circuit signal to turn on a district light installed in the fire alarm body, and also sends a transfer signal to a sub-receiver to display the location of the fire and control the disaster prevention device. , the signal from the sensor is connected to the signal input terminal of the first-stage detection circuit, and the signal from the sensor is connected to one end of a test switch via a diode, and the first-stage detection circuit The signal output end of the first stage delay relay is connected to one end of the test switch via the relay contact of the first stage delay relay, and the signal output end of the first stage detection circuit is connected in series with the first stage delay relay and the first stage district light. connected to the other end of the test switch through a circuit, and connected to the transfer terminal of the sub-receiver through another relay contact of the first-stage delay relay;
The activation of the sensor activates the first-stage delay relay to turn on the first-stage district light, and by closing the relay contact of the first-stage delay relay, the next-stage detection circuit is activated to turn on the next-stage district light. A test circuit for a fire alarm system, characterized in that a light is turned on and at the same time a sub-receiver is operated by closing another relay contact of the delay relay, and all detection circuits are similarly operated in a chained manner.