JP2000287384A - Power device for disaster-preventive monitor control panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To rapidly conduct changeover to power supply from a battery in the case of service interruption or the like by a simple circuit by monitoring AC output voltage from a transformer, changing over power supply to one by a power supply circuit when AC output voltage is higher than fixed set voltage, and changing over power supply to one from the battery when AC output voltage is lower than fixed set voltage. SOLUTION: An AC voltage detector 12 turns the second voltage-detecting switch circuit 13 on when DC voltage corresponding to AC output voltage from a transformer 8 exceeds a threshold value V th2, and supplies each system of the inside, the outside 1 and the outside 2 with DC voltage from power supply circuits 1a-1c. When service interruption is generated in a commercial AC power 2, on the other hand, input voltage slowly lowers by the back-up functions of capacitors C1-C3. The AC voltage detector 12 turns the second voltage- detecting switch circuit 13 off, and power supply is changed over to one from a battery 3. Accordingly, power supply can be changed over to one from the battery 3 at approximately the same time as service interruption.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply device for a disaster prevention monitoring control panel which switches to power supply from a battery at the time of a power failure and continuously monitors for abnormalities such as a fire.

[0002]

2. Description of the Related Art Conventionally, in this kind of disaster prevention monitoring control panel, a power supply system is divided into a plurality of systems, and a power supply circuit using a switching regulator or the like is provided for each system to supply power. .

FIG. 5 shows an example of a conventional power supply device, in which power is supplied to an internal system and an external system separately.
Power supply circuit (power supply: PS) 100 for each system
a and 100b are provided to convert the AC input of the commercial AC power supply 102 into a DC voltage of, for example, 24 volts and supply the DC voltage to each system.

[0004] A battery 103 is provided for backup in the event of a power failure, so that power can be supplied by switching to the battery 103 upon detection of a power failure. For this purpose, the switching relay contacts nv1 and nv2 of the relays NV1 and NV2 are connected to the a side of the battery 103 and the b side is connected to the power supply circuit 100.
a, 100b.

The battery 103 reduces the AC voltage from the commercial AC power supply 102 with a transformer 108 and
By rectifying at 9, the battery is always charged.

The relays NV1 and NV2 are connected to a voltage detection circuit 1
04a, 104b and voltage detection switch circuit 105a, 1
05b. When a power failure occurs in the commercial AC power supply 102, the power supply voltage from the power supply circuits 100a and 100b decreases, and the voltage detection circuits 104a and 104b operate when the voltage drops below a predetermined set voltage.
a, 105b are turned off, and the relays NV1, NV2 are restored. For this reason, the switching relay contacts nv1 and nv2
Side, and the power is supplied from the battery 103.

For battery testing, battery test switching circuits 106a and 106b and test switch circuits 107a and 107b are provided for each system. When the CPU issues a test instruction to the battery test circuits 106a and 106b, the test switch circuits 107a and 107b are turned off, the relays NV1 and NV2 are restored, and the switching relay contacts n
By switching v1 and nv2 to the a side and switching to power supply from the battery 103, a battery test is performed to determine whether power supply from the battery can be performed normally for a specified time.

[0008]

However, in such a conventional power supply device, the power supply circuit 100
a, 100b, large capacity capacitors C1 and C2 are connected to the output part of the power supply line to the load or in the power supply device, and when the load for supplying power is light, the power supply to the battery when the commercial AC power supply fails There is a problem that switching is slow.

That is, since the large-capacity capacitors C1 and C2 are connected to the power supply line, when the load for supplying power is light, the power supply voltage is slowed down by the capacitors C1 and C2 at the time of a power failure. Relay NV
1, NV2 switching is delayed. For this reason, the detection accuracy of the voltage detection circuit must be increased, and there is a problem that the circuit becomes complicated.

In particular, since the number of loads connected to the outside, for example, the number of district sound devices and smoke evacuating devices, is determined by the size of the building, such a problem is likely to occur when the number of connections is reduced. Become.

The present invention has been made in view of such a conventional problem, and even when a large-capacity capacitor is connected to a power supply line, switching to power supply from a battery at the time of a power failure or the like is possible. An object of the present invention is to provide a power supply device for a disaster prevention monitoring control panel that can be quickly operated with a simple circuit.

[0012]

In order to achieve this object, the present invention is configured as follows. First, a power supply device for a disaster prevention monitoring and control panel according to the present invention includes a transformer for converting an AC input voltage from a commercial AC power supply to a predetermined voltage and inputting the converted voltage to a charging circuit, a battery charged by a rectified output voltage of the charging circuit, and a commercial power supply. A power supply circuit that converts an AC input voltage from an AC power supply into a predetermined DC power supply voltage and supplies the load to a load, and a power supply provided on an output side of the power supply circuit and switching between power supply by the power supply circuit and power supply by a battery A switching relay;
Monitors the DC power supply voltage from the power supply circuit, activates the power supply switching relay when the voltage is higher than the specified voltage, and switches to the power supply from the power supply circuit. And a DC power supply monitoring circuit for restoring the power supply and switching to power supply from a battery.

According to the present invention, a power supply device for such a disaster prevention monitoring control panel monitors an AC output voltage from a transformer and activates a power supply switching relay when the voltage is higher than a predetermined set voltage, thereby enabling a power supply circuit. And an AC power supply monitoring circuit for restoring the power supply switching relay and switching to power supply from a battery when the voltage is lower than a predetermined set voltage.

Here, the DC power supply monitoring circuit comprises: a DC voltage detection circuit for outputting a voltage detection signal according to a case where the DC power supply voltage from the power supply circuit is higher or lower than a predetermined set voltage; A first voltage detection switch circuit that is turned on by a voltage detection signal from the DC voltage detection circuit when the voltage is higher than a predetermined set voltage, and is turned off by a voltage detection signal when the voltage is lower than the predetermined set voltage.

The AC power supply monitoring circuit includes an AC voltage detection circuit that outputs an AC voltage detection signal according to a case where the AC output power supply voltage from the transformer is higher or lower than a predetermined set voltage; And a second voltage detection switch circuit that is turned on by a voltage detection signal from an AC voltage detection circuit when the voltage is higher than a predetermined voltage and turned off by a voltage detection signal when the voltage is lower than a predetermined voltage.

The first voltage detection switch circuit and the second
Connect the voltage detection switch circuit in series with the power supply switching relay,
When one of the switch circuits is turned off, the power supply switching relay is restored, and the power supply is switched to the power supply from the battery.

According to the power supply device of the present invention, the AC output voltage of the battery charging transformer is constantly monitored, and when the AC output voltage becomes lower than the set voltage, the power supply switching relay in the operating state is restored. Even if the DC power supply monitoring circuit has a delay in detecting a voltage drop at light load due to a large-capacitance capacitor on the output side, the power supply from the battery is immediately monitored by monitoring the AC output voltage. Can be switched to supply.

When the power supply device for a disaster prevention monitoring and control panel according to the present invention has a plurality of power supply systems, a power supply circuit and a power supply switching relay are provided for each of the plurality of power supply systems. A plurality of DC voltage detection circuits that are provided for each power supply circuit and output a voltage detection signal corresponding to a case where the power supply voltage is higher and lower than a predetermined set voltage, and a detection signal of the plurality of DC voltage detection circuits. When all of them are higher than the predetermined set voltage, the power supply relays are switched to the power supply from each power supply circuit by operating a plurality of power supply switching relays collectively, and when any of the detection signals is lower than the predetermined set voltage, A switching control circuit for switching to power supply from a battery by collectively restoring a plurality of power switching relays.

More specifically, the switching control circuit is turned on by a voltage detection signal from the DC voltage detection circuit when the DC power supply voltage is higher than a predetermined set voltage, and turned off by a voltage detection signal when the DC power supply voltage is lower than the predetermined set voltage. A series switch circuit in which a plurality of first voltage detection switch circuits are connected in series, a relay drive circuit in which a plurality of power supply switching relays are connected in parallel, and a power supply state signal which is connected in parallel to the relay drive circuit and indicates a power supply switching state;
And a test switch circuit that is turned on and off by a battery test instruction from the CPU. A series switch circuit, a relay drive circuit, and a test switch circuit are connected in series, and at least a plurality of switch circuits are connected. It is characterized in that a plurality of power supply switching relays are collectively restored when any one of them is turned off.

Further, the plurality of DC voltage detection circuits include a comparator, and the comparator has a DC power supply voltage of the first.
A switch-on voltage detection signal is output when the threshold voltage is exceeded, and then a second power supply voltage lower than the first threshold voltage is output.
It has a hysteresis detection characteristic of outputting a switch-off voltage detection signal when the voltage falls below a threshold voltage.

For this reason, a circuit for sending a state signal indicating a power supply switching state to the CPU for a plurality of power supply systems, and a battery switching test circuit for switching a power supply switching relay for a battery test or the like according to an instruction from the CPU are a single circuit. In order to increase the number of power supply systems, the power supply circuit, voltage detection circuit, voltage detection switch circuit, and power supply switching relay need only be added. Can respond.

[0022]

FIG. 1 is a circuit block diagram of an embodiment of a power supply device for a disaster prevention monitoring control panel according to the present invention.

In FIG. 1, three AC power supply circuits 1a, 1
b and 1c are provided to individually supply DC power to the inside of the disaster prevention monitoring control panel, the outside 1 for district sound, and the outside 2 for smoke prevention.

As the power supply circuits 1a to 1c, for example, switching regulators are used, and a commercial AC voltage is input.
The output is converted to a predetermined DC power supply voltage. Here, the power supply circuit 1a for supplying power to the inside of the disaster prevention monitoring control panel is D
Supply C24V, and external 1, for area sound and smoke prevention
The power supply circuits 1b and 1c for supplying power to the external 2 supply, for example, 26.4 V DC.

The power supply shown in FIG. 1 has a battery 3 for backing up the power supply when the commercial AC power supply 2 fails.
Is provided. The battery 3 inputs an AC power supply voltage from the commercial AC power supply 2 to the transformer 8 and outputs a predetermined AC output voltage V
It is converted to AC, for example, AC56V, rectified by the charging circuit 9, and the battery 3 is constantly charged.

In order to switch to the power supply of the battery 3 in the event of a power failure, three power supply switching relays NV1, NV2, NV corresponding to the respective power supply systems from the power supply circuits 1a to 1c.
3 are provided. The power switching relays NV1 and NV
2, NV3 have switching relay contacts nv1, nv2, nv3, the a side is connected to the battery 3, the b side is connected to the output from the power supply circuits 1a to 1c, and the switching contacts are internal, external 1, external 2 Side is connected to the power line on the load side.

As will be described later, the power supply relays NV1 to NV3 allow the power supply circuits 1a to 1c to normally supply the DC power supply voltage based on the AC power supply from the commercial AC power supply 2. When they are in operation, all of them are activated, and the switching relay contacts nv1 to nv3 are switched to the b side to supply the DC power supply voltage from the power supply circuits 1a to 1c to the internal, external 1 and external 2 respectively.

On the other hand, the power supply circuit 1
When the power supply voltage from a to 1c is cut off, power supply switching relay N
V1 to NV3 are restored, and the switching relay contacts nv1 to nv3
Is switched to the a side to switch to the power supply from the battery 3.

Such power switching relays NV1 to NV3
The switching control of the operation and the recovery is performed by the DC voltage detection circuits 4a and 4
b, 4c, first detection voltage switch circuits 5a, 5b, 5c
This is performed by a DC power supply monitoring circuit including

The DC voltage detection circuits 4a to 4c input the DC output voltages of the power supply circuits 1a to 1c to built-in comparators and compare the DC output voltages. To turn on the first voltage detection changeover switches 5a to 5c. When the DC power supply voltage is lower than a predetermined set voltage, the DC voltage detection signal is set to L level,
The first voltage detection switch circuits 5a to 5c are turned off.

In this embodiment, the comparators provided in the DC voltage detection circuits 4a to 4c have a hysteresis characteristic. Assuming that the power supply voltage for the inside of the power supply circuit 1a is DC 24V, and the power supply voltage for the outside 1 and the outside 2 for the district sound and smoke prevention by the power supply circuits 1b and 1c is 26.4V DC, a DC voltage detection is performed. Two threshold voltages Vth1 and Vth2 are set in comparators provided in the circuits 4a to 4c.

In the case of the DC voltage detection circuit 4a for monitoring 24V DC, this threshold voltage is Vth1 = 16V, Vth2
= 23V and DC voltage detection circuits 4b and 4c monitoring DC 26.4V, Vth1 = 19V, Vth2 =
25V.

FIG. 2 shows the DC voltage detection circuits 4a to 4c of FIG.
Shows the hysteresis characteristics of the comparator provided in FIG.
Two threshold voltages V for the input power supply voltage shown on the horizontal axis
th1 and Vth2 are set, and the comparator generates an L level output or an H level output according to the input power supply voltage.

When the input power supply voltage increases from 0 V,
Even when the voltage reaches the first threshold voltage Vth1, it does not rise to the H level, and when it reaches the higher threshold voltage Vth2, the comparator output rises to the H level. After the output of the comparator rises to the H level, it does not fall to the L level even if the power supply voltage falls below the higher threshold voltage Vth2, and rises to the L level when the power supply voltage falls below the lower threshold voltage Vth1. Go down. Thus, the output of the comparator has a hysteresis characteristic with respect to the input of the power supply voltage.

Referring again to FIG. 1, three first voltage detection switch circuits 5a to 5c that are turned on and off by voltage detection signals from the DC voltage detection circuits 4a to 4c are connected in series. On the other hand, a parallel circuit of three power supply switching relays NV1 to NV3 is connected in series.

Further, the power supply switching relays NV1 to NV3 include:
A light emitting element 10 of a photocoupler for transmitting a power supply switching state to a control CPU is connected in parallel. Further, a test switch circuit 7 is connected in series to a parallel circuit of the power supply switching relays NV1 to NV3. Test switch circuit 7
Is turned on and off by the output of the battery switching test circuit 6 which operates in response to a battery test instruction from the CPU.
Normally, the test switch circuit 7 is in the ON state and the CPU
When a battery test instruction is given to the battery switching test circuit 6 from the above, the test switch circuit 7 is turned off.

According to the present invention, the DC power supply monitoring circuit is provided with an AC power supply monitoring circuit on the side of the transformer 8 and the charging circuit 9 provided for the battery 3. This AC power supply monitoring circuit includes an AC voltage detection circuit 12 and a second voltage detection switch circuit 13.

The AC voltage detection circuit 12 receives, for example, AC56V output from the transformer 8, detects whether the voltage is higher or lower than a predetermined voltage, and outputs a voltage detection signal to the second voltage detection switch circuit 13. Turn on and off. Specifically, the AC voltage detection circuit 12 rectifies and smoothes the AC output voltage AC56V from the transformer 8 to convert it to a DC voltage, and then detects the voltage by a comparator similar to the DC voltage detection circuits 4a to 4c.

For example, an AC output voltage AC from the transformer 8
Since 56 V becomes DC 26.4 V by rectifying and smoothing to DC similarly to the rectified output by the charging circuit 9, two comparators, Vth1 = 25V and Vth2 = 42V, are set in the comparator. 8 to detect a change in the AC output voltage AC37V.

The second voltage detection switch circuit 13 is connected in series with the first voltage detection switch circuits 5a to 5c on the DC power supply monitoring circuit side, and is also connected to the power supply switching relays NV1 to NV3 by the voltage detection signal of the AC voltage detection circuit 12. Switching to power supply from the battery 3 upon recovery is enabled.

Further, an integrating circuit 11 is provided on the DC power supply monitoring circuit side.
And a DC voltage detection circuit 4 provided in a power supply system for the area 1 and the area 2 serving as the outside 1 and the outside 2 for smoke and smoke control.
b, 4c to suppress the fluctuation of the power supply voltage due to an instantaneous interruption or the like.
No malfunction is caused in b and 5c.

FIG. 3 is a time chart of the operation of the power supply circuit 1b, the DC voltage detection circuit 4b, and the integration circuit 11, which are the power supply system of the outside 1 in FIG.

Assuming that the DC power supply voltage VDC from the power supply circuit 1b is momentarily interrupted as shown in FIG. 3A, the comparator of the DC voltage detection circuit 4b responds to the threshold values Vth1 and Vth2 in FIG. A voltage detection signal that instantaneously falls to the L level and rises to the H level is output.

This voltage detection signal is input to the integration circuit 11, and since the integration circuit has a sufficient time constant for the instantaneous interruption time, the fluctuation of the voltage detection signal is suppressed, and the integration as shown in FIG. Output is made. Therefore, the first voltage detection switch circuit 5b does not turn off due to an instantaneous interruption of the power supply voltage, and can stably maintain the on state. The same applies to the instantaneous interruption in the DC power supply voltage of the external device 2 for supplying power for smoke emission control.

The DC voltage detection circuit 4a for detecting the power supply voltage for supplying power to the inside of the disaster prevention monitoring control panel is relatively stable because power is not supplied to the outside, and instantaneous interruption is possible. Since there is no possibility, the voltage is supplied directly to the first voltage detection switch circuit 5a without passing through the integration circuit 11, but it may be passed through the integration circuit 11 if there is a possibility of momentary interruption. .

As the first voltage detection switch circuits 5a to 5c, the second voltage detection switch circuit 13, and the test switch 7, appropriate switch circuits such as relays, transistors, and thyristors can be used.

Further, in this embodiment, relatively large-capacity capacitors C1, C2, and C3 are connected to the output-side lines of the internal, external 1, and external 2 power supply systems. Even if the supply of the DC power from the circuits 1a to 1c is cut off, the DC power supply voltage gradually decreases due to the backup of the capacitors C1 to C3. The degree of the decrease in the DC power supply voltage becomes even slower when the load supplied to each load is small and the load is light.

Next, the operation of the embodiment shown in FIG. 1 will be described. When the power switch provided on the disaster prevention monitoring control panel is turned on,
An AC power supply voltage is input from the commercial AC power supply 2, and the power supply circuits 1a to 1c operate to supply a predetermined DC power supply voltage to each of the inside, the outside 1, and the outside 2.

In response to the output of the DC power supply voltage, the DC voltage detection circuits 4a to 4c output the higher threshold Vth of the comparator.
When it exceeds 2, the voltage detection signal is set to the H level, and the first voltage detection switch circuits 5a to 5c are turned on. At the same time, a predetermined AC output voltage is obtained from the transformer 8 by power supply from the commercial AC power supply 2, and charging of the battery 3 is started by rectification by the charging circuit 9.

At this time, the AC voltage detection circuit 12 sets the voltage detection signal to the H level when the DC voltage corresponding to the AC output voltage of the transformer 8 exceeds the threshold value Vth2, and turns on the second voltage detection switch circuit 13.

Here, since the test switch circuit 7 is in the ON state, the power supply switching relays NV1 to NV
V3 operates collectively, and the switching relay contacts nv1 to nv3
To the b side, and supplies the DC power supply voltage from the power supply circuits 1a to 1c to the internal, external 1 and external 2 systems.

In such a normal power supply state, for example, if a power failure occurs in the commercial AC power supply 2, the power supply circuits 1a to 1a
Although the output voltage of 1c is cut off, the input voltage to the DC voltage circuits 4a to 4c gradually decreases due to the backup function of the capacitors C1 to C3 provided on the output side of the power supply line.

On the other hand, the AC output voltage from the transformer 8 is cut off at the same time as the power failure, so that the AC voltage detection circuit 1
The voltage detection signal from 2 falls from the H level to the L level immediately after the power failure, and turns off the second voltage detection switch circuit 13. Therefore, the power supply switching relay N connected in parallel
V1 to NV3 are restored simultaneously, and the switching relay contacts nv1 to nv1
When nv3 is switched to the side a, the power supply is switched from the battery 3.

As described above, even if the power supply from the power supply circuits 1a to 1c to the battery 3 is instantaneously interrupted due to the switching of the power supply to the battery 3, the large-capacity capacitors C1, C2, There is no effect on each load due to the backup of C3.

FIG. 4 is a time chart of the output of the transformer output voltage VAC, the DC power supply voltage VDC, the DC voltage detection circuit 4b, and the output of the AC voltage detection circuit 12 when the commercial AC power supply fails.

As shown in FIG. 4A, when the commercial AC power supply 2 experiences a power failure, the transformer output voltage VAC immediately drops to 0V. On the other hand, as shown in FIG. 4B, for example, the DC power supply voltage VDC of the power supply line from the power supply circuit 1b to the outside 1 is gradually decreased by the capacitor C2.

At this time, according to the present invention, since the AC voltage detecting circuit 12 for detecting the output voltage of the transformer 8 is provided, the AC voltage detecting circuit 12 is provided almost simultaneously with the power failure as shown in FIG. Falling from H level to L level,
By turning off the second voltage detection switch circuit 13, the power supply switching relays NV1 to NV3 are restored, and the power supply is switched to the power supply from the battery.

On the other hand, in the DC voltage circuit 4b of the power supply line to which the capacitor C1 is connected, FIG.
At time t2 when the DC power supply voltage delayed from the power failure at time t1 falls below the lower threshold voltage Vth1 of the comparator as in (D), the voltage detection signal is set to L level and the first voltage detection switch circuit 5b is turned off. .

For this reason, in contrast to the conventional switching to the standby power supply by monitoring the DC power supply voltage, the switching to the standby power supply by monitoring the AC power supply of the present invention does not cause a delay such as from time t1 to time t2. It is possible to switch to the power supply from the battery 3 almost simultaneously with the power failure.

On the other hand, when the DC output voltage is lowered or cut off due to, for example, a failure of the power supply circuit 1b instead of the power failure of the commercial AC power supply 2, the DC power supply voltage is reduced by the capacitor C2 as shown in FIG. The DC voltage circuit 1 drops slowly and delays to some extent after the power failure due to a failure.
The voltage detection signal from b falls to the L level, and the power supply from the battery 3 is switched.

Further, when the CPU issues a battery test instruction in accordance with the operation of the battery test switch, the battery switching test circuit 6 turns off the test switch circuit 7 which is in the ON state, and thereby the power supply switching relays NV1 to NV3 are collectively operated. Then, the internal system, the external system 1 and the external system 2 are switched to the power supply from the battery 3, and a battery test is performed to determine whether the power supply from the battery 3 can be performed normally for a specified time.

Further, in the embodiment of FIG. 1, a plurality of DC power supply voltage supply systems are provided.
The light emitting element 10 of the photocoupler for notifying the U of the power switching state, the battery switching test circuit 6 for the battery test, and the test switch circuit 7 are provided as a single common circuit without being provided for each system. Therefore, as compared with the case where all the circuits are independently provided for each system as in the conventional device of FIG. 5, the circuit configuration when the number of power supply systems is increased can be simplified and the cost can be reduced.

In the above-described embodiment, the case where the supply system of the DC power supply voltage is three is taken as an example.
It may be a single system or an appropriate number of multiple systems. Thus, even if the supply system of the DC power supply voltage increases, the circuit configuration of each system is the same, and the number of series connection of the first voltage detection switch circuit and the number of parallel connection of the power supply switching relay increase according to the number of systems. .

The present invention is not limited to the above embodiments, includes appropriate modifications that do not impair the objects and advantages thereof, and is not limited by the numerical values shown in the above embodiments.

[0065]

As described above, according to the present invention, the AC output voltage from the battery charging transformer is constantly monitored, and when the AC output voltage falls below the set voltage, the battery is in the operating state. To restore the power supply switching relay and switch to the power supply from the battery, a large-capacity capacitor is connected to the output side of the DC power supply monitoring circuit. The monitoring can immediately switch to the power supply from the battery in response to a voltage drop such as a power failure, and a highly reliable battery backup can be realized.

When a plurality of power supply systems of the DC power supply are provided, a circuit for transmitting a state signal indicating a power supply switching state to the control CPU in accordance with the number of power supply systems is provided. The battery switching test circuit that switches the power switching relay to the battery side can be shared by a single circuit, and when the number of power supply systems is increased, the circuit configuration is significantly larger than that of a conventional device in which all circuits are provided for each power supply system There is no need to change to, and it can be easily handled.

[Brief description of the drawings]

FIG. 1 is a circuit block diagram showing an embodiment of a power supply device for a disaster prevention monitoring control panel according to the present invention.

FIG. 2 is an explanatory diagram of a hysteresis characteristic of the voltage detection circuit of FIG.

FIG. 3 is an explanatory diagram of voltage fluctuation characteristics at the time of an instantaneous interruption by the integration circuit of FIG. 1;

FIG. 4 is a time chart of a power switching operation at the time of a power failure.

FIG. 5 is a circuit block diagram of a conventional device.

[Explanation of symbols]

 1a to 1c: power supply circuit (PS1 to PS3) 2: commercial AC power supply 3: battery 4a to 4c: DC voltage detection circuit 5a to 5c: first voltage detection switch circuit 6: battery switching test circuit 7: test switch circuit 8 : Transformer 9: Charging circuit 10: Light emitting element (for sending CPU) 11: Integrating circuit 12: AC voltage detecting circuit 13: Second voltage detecting switch circuit

Continued on the front page F-term (reference)

Claims (5)

[Claims] A transformer for converting an AC input voltage from a commercial AC power supply into a predetermined AC output voltage and supplying the AC output voltage to a charging circuit; a battery charged by the rectified output voltage of the charging circuit; A power supply circuit for converting an AC input voltage into a predetermined DC power supply voltage and supplying the load to a load; a power supply switch provided on an output side of the power supply circuit and switching between power supply by the power supply circuit and power supply by the battery A relay, monitors a DC power supply voltage from the power supply circuit, and activates the power supply switching relay to switch to power supply from the power supply circuit when it is higher than a predetermined set voltage. A DC power monitoring circuit for restoring the power switching relay when low and switching to power supply from the battery; and In the above, the AC output voltage from the transformer is monitored, and when the voltage is higher than a predetermined set voltage, the power supply switching relay is made operable to enable switching to the power supply from the power supply circuit. A power supply unit for a disaster prevention monitoring control panel, further comprising: an AC power supply monitoring circuit that recovers the power supply switching relay and switches to power supply from the battery when the power supply relay is low. 2. The power supply for a disaster prevention monitoring and control panel according to claim 1, wherein said DC power supply monitoring circuit is provided when the DC power supply voltage from said power supply circuit is higher or lower than a predetermined set voltage. A DC voltage detection circuit that outputs a corresponding voltage detection signal; and, when the DC power supply voltage is higher than a predetermined set voltage, turned on by a voltage detection signal from the DC voltage detection circuit, and when the DC power supply voltage is lower than a predetermined set voltage. A first voltage detection switch circuit that is turned off by the voltage detection signal of the above. The AC power supply monitoring circuit further comprises: an AC voltage corresponding to a case where the AC output power supply voltage from the transformer is higher or lower than a predetermined set voltage. An AC voltage detection circuit that outputs a detection signal; and an AC voltage detection circuit that is turned on by a voltage detection signal from the AC voltage detection circuit when the AC power supply voltage is higher than a predetermined set voltage, and is turned on when the AC power supply voltage is lower than the predetermined set voltage. A second voltage detection switch circuit that is turned off by the voltage detection signal of the above. The first voltage detection switch circuit and the second voltage detection switch circuit are connected in series to the power supply switching relay, and when one of the switch circuits is turned off. A power supply device for a disaster prevention monitoring control panel, wherein the power supply switching relay is restored to switch to power supply from a battery. 3. A power supply device for a disaster prevention monitoring control panel according to claim 1, wherein when a plurality of power supply systems are provided, the power supply circuit and the power supply switching relay are provided for each of the plurality of power supply systems. A plurality of DC voltage detection circuits provided for each of the plurality of power supply circuits and outputting a voltage detection signal corresponding to a case where the power supply voltage is higher or lower than a predetermined set voltage, When all of the detection signals from the plurality of DC voltage detection circuits are higher than a predetermined set voltage, the plurality of power supply switching relays are collectively operated to switch to power supply from each of the power supply circuits, A switching control circuit for switching to power supply from the battery by collectively restoring the plurality of power switching relays when any of the detection signals is lower than a predetermined set voltage; And a power supply unit for a disaster prevention monitoring control panel. 4. The power supply device for a disaster prevention monitoring control panel according to claim 3, wherein the switching control circuit detects a voltage from the DC voltage detection circuit when the DC power supply voltage is higher than a predetermined set voltage. A series switch circuit in which a plurality of first voltage detection switch circuits that are turned on by a signal and turned off by a voltage detection signal when the signal is low are connected in series; a relay drive circuit in which the plurality of power supply switching relays are connected in parallel; and the relay drive circuit A light-emitting element of a photocoupler that is connected in parallel to the power supply and transmits a power state signal indicating a power switching state; and a test switch circuit that is turned on and off by a battery test instruction from the CPU. The test switch circuits are connected in series, and when at least one of the plurality of switch circuits is turned off, the plurality of power supply switching relays are collectively restored. A power supply circuit for a disaster prevention monitoring and control panel. 5. The power supply device for a disaster prevention monitoring control panel according to claim 4, wherein the plurality of DC voltage detection circuits include a comparator, and the comparator is turned on when the power supply voltage exceeds a first threshold voltage. And outputting a voltage detection signal for the second power supply voltage lower than the first threshold voltage.
A power supply device for a disaster prevention monitoring and control panel, which has a hysteresis characteristic of outputting a voltage detection signal for switching off when a voltage falls below a threshold voltage.