JPS59169338A - Preliminary power source testing circuit - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention]

The present invention relates to a backup power supply test circuit for testing a backup power supply of a fire alarm system or the like under an actual load. Conventionally, testing of a standby power supply with an actual load has been carried out by simply switching to the standby power supply with a changeover switch and measuring the load supply voltage with a voltmeter. However, in recent years, many fire alarm systems have built-in microcomputers, so the conventional method described above may cause the program to run out of control in the event of a failure of the σ standby power supply, etc. There is a risk that your memory may disappear or change. SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned conventional drawbacks and to provide a standby power supply test circuit that can switch the standby power supply without momentary interruption and can immediately supply load power from the main power supply in the event of a failure of the standby power supply. . In the test circuit of the present invention, the load voltage is equal to or higher than a predetermined value in the test circuit of the present invention, which is connected in parallel to the load through a diode, and which tests the power source with an actual load. a voltage detection circuit that detects whether the voltage is high, a manual operation switch that closes during the test, a gate that is opened by the output of the voltage detection circuit, and a gate that is inserted into the output circuit of the main power supply and normally connects the main power supply to the load. The present invention is characterized by comprising a switching circuit that is opened when the output signal of the operation switch is input through the gate. Next, the present invention will be explained in detail with reference to the drawings. FIG. 1 is a circuit diagram showing an embodiment of the present invention. That is, a DC voltage of about 24V is supplied to the load by the constant voltage power supply E, and the 24V voltage is converted to a DC voltage of about 5V by the 1Dc-DC converter 1 to supply the operating voltage for a microcomputer, etc. ing. Backup power supply E
, [connected to the load Ki column via diode 2. The voltage of the backup power source 4 is set to be much lower than the 24 V mentioned above, and since a reverse voltage is always applied to the diode 2, it is in an off state. When the main power supply E+ fails, the load voltage decreases, and as the diode 2 turns on, load power is supplied from the standby power supply E without momentary interruption. Further, a switching circuit 3 is inserted between the main power source and the load, and when the switching circuit is turned off, the main power source is interrupted and the load current is supplied by the standby power source 4 in the same manner as described above. The output voltage Fi is monitored by the voltage detection circuit 4, and the voltage detection circuit 4 outputs a high level when the voltage is, for example, 85 times higher than the rated voltage [7], and outputs a low level when the voltage is lower than the 85 times the rated voltage. However, even if a voltage of 85 or higher is input again after a low level is outputted, the low level output is maintained. 'Gate 5' according to the output 1/r of the tf pressure detection circuit 4? i-opening/closing wholesale 1i? l1I
The input of the gate 5 is connected via a manually operated switch 6 which is closed during the test. Therefore, the switching circuit 3 is opened by the output of the gate 5.゛Next, I will explain the operation of this embodiment. Reserve lightning, Geng
, f When testing is to be performed, when the operation switch 6 is pressed to close the contact, the output of the gate 5 is at a high level and the switching circuit 3 is opened, and the output from the power source E to the load is passed through the diode 2. Voltage is supplied. If the backup power source E is normal, the load voltage is slightly lower than 24V, but is at least 85V. Therefore, the voltage detection circuit 4 continues to output a high level, and the gate 5 remains open. Backup power supply E. 1. is defective, for example, the output voltage gradually decreases due to temporary power supply. (When the output of the voltage detection circuit 4 becomes low level and the gate 5 closes. Therefore, the switching circuit 3 is closed and the load' current is supplied from the main power supply E. During this time, the DC- DC converter 1
However, the output is directly controlled at a constant level of about 5V, and the microcomputer etc. can operate normally. Runaway programs and loss of newt contents will not occur. The low level output of the voltage/voltage detection circuit 4 is maintained at a constant CC by the flip-flop shown in the figure, and a failure of the backup power supply is indicated by the strong indicator light shown in the figure. Also,
Switching circuit 3 on

[(Even if the voltage of the bus 7 returns to normal again, the output of the voltage detection circuit 4 remains at a low level, and phenomena such as vibrations are unlikely to occur.The backup power supply E is completely defective, and for example When the output circuit is disconnected, it is desirable to connect a capacitor 8 to the bus bar 7 in order to prevent a momentary disconnection from occurring when the switching circuit 3 is opened. Since the switching circuit 3 is closed when the voltage charged in the battery 8 drops by 85%, instantaneous power outages are likely to occur. Fig. 2 is a block diagram showing another embodiment of the present invention. , 100V commercial power source is stepped down with a transformer 10, rectified and smoothed with a rectification and smoothing circuit 11, and a main type of approximately 24V is obtained.
On the other hand, the charging circuit 12 trickle-charges the backup power source E with a minute current. The output voltage of the backup power source E is approximately 24V. Backup power supply 4
The output voltage of the constant voltage circuit 13 is input to the constant voltage circuit 13, and the output voltage of the constant voltage circuit 13 is, for example, about 23V, which is slightly lower than the output voltage of the main power supply. The output of the constant voltage circuit 13 is connected to the diode 2
It is connected to the bus bar 7 via. On the other hand, the rectifier circuit 11
The output of is normally connected to mother #7 through the switching circuit 3 and the second diode 14 for preventing jamming. Therefore, the bus line 7KH main lightning, about 24V from the source
The voltage is supplied and outputted to the load, and is converted into a DC voltage of approximately 5 cm by the DC-DC converter IK, which is used as the operating voltage for a microcomputer, etc. Since the output voltage of the constant/adjustable voltage circuit 13 is lower than the voltage of the mother @7, a reverse voltage is applied to the diode 2, and it is in an off state. The relay 15 is operated by the output of the switching circuit 3,
The normally closed contact 16 of the relay 5 is connected between the standby power supply E and the bus bar 7. Further, on the output side of the second diode 14, a pseudo load resistor 17 and a second switching circuit 18 are connected.
A series connection circuit is connected. The voltage on the bus 7 is detected by the voltage detection circuit 4. A high level is output to the voltage detection circuit 4 with a voltage of 85% or more of the rated voltage (24V) to open the gate 5, and a voltage of 85% or less closes the gate 5. The output of the gate 5 is input to an integrating circuit consisting of a resistor 19 and a capacitor 20, and the output of the integrating circuit is connected to the entire switching circuit 3 and the second switching circuit 18.
Supplied to the control input terminal of The switching circuit 3 and the second switching circuit 18 are switches that open and close via active regions when the output voltage of the integrating circuit changes from low level to high level. In other words, during the opening/closing operation, the resistance value changes depending on the control input voltage, causing noise due to sudden changes in the stain flow, and the operating time of the lightning, pressure detection circuit 4° switching circuits 3, 18, etc. This prevents the output voltage from dropping more than expected due to delays. This is desirable from the standpoint of preventing the microcomputer from running out of control. Note that the pseudo load resistance 17 is set to have a force resistance value of 1 so that the maximum load current flows together with the actual load. The test operation switch 6 is connected between the bus 7 and the input of the gate 50, and is also connected to the reset terminal R of the flip-flop 21. The set terminal SKl"tt of the flip-flop 21 is inputted with the output of the voltage detection circuit. The output of the flip-flop 21 operates the standby power supply abnormality display circuit 22, and the inverted output is connected to one input terminal of the gate 5. Next, the operation of the embodiment will be explained. When the operating switch 6 for testing is closed, the output of the gate 5 becomes high level, and the capacitor 20 is charged through the resistor 19. As the voltage of the capacitor 20 increases, As a result, the resistance of the switching circuit 3 increases, and the switching circuit 3 eventually enters the off state.
- The switching circuit 18 of the power of 2 moves from an off state to an on state via an active region. The off relay 15 of the switching circuit 3 is restored and the normally closed contact 16 is closed. During the recovery time of the relay 15, the output of the constant voltage circuit 13 is outputted to the bus bar 7 through the diode 2, so a momentary interruption occurs. Then, the output of the backup power supply E is normally closed contact 1.
6f is supplied to the bus 7, and the load and pseudo load 17
Power is supplied to the That is, the test is performed using the standby power source F and the maximum load including the actual load. Also, DC-DC
The output of the converter 1 supplies an operating ME for a microcomputer or the like. The voltage of the bus bar 7 is monitored by a voltage detection circuit 4. When the power source E is defective (defect, photoelectric defect, insufficient capacity, etc.), the voltage of the capacitor 8 connected to the bus bar 7 rapidly decreases and gradually decreases to less than 85% of the rating. When the voltage is on, the output of the voltage detection circuit 4 becomes low level, the flip-flop 21 is set, and the standby power supply abnormality display circuit 22 indicates that the standby power supply is defective. At the same time, the gate 5 closes, its output goes low, the switching circuit 3 opens, and the second switching circuit 18 opens. As a result, voltage is supplied to the bus 7 from the main power supply, and the current flowing through the pseudo load resistor 17 is turned off. Therefore, instantaneous interruptions will not occur. Even if the output of the voltage detection circuit 4 is at a high level, the 5-gate flip-flop 2
Since it is turned off by the inverted output q of gate 1, the output of gate 5 remains at a low level, and phenomena such as vibration do not occur. On the other hand, when the switching circuit 3 is turned on, the relay 15
operates and the normally closed contact 16 opens. Therefore, the output of the standby power supply E2 is cut off by the diode 2 and is supplied to the mother #i17.
2 will be eliminated. The same applies even if the constant voltage circuit 13 is not used and the output voltage of the backup power source E is lowered by a step-down circuit such as a voltage divider circuit and connected to the anode of the diode 2. As such, in the present invention, when performing an actual load test on a standby power supply, the standby power supply output is connected to the load via a diode, and the switching circuit of the main power supply is turned off to switch to the standby power supply without momentary interruption. When the load voltage drops below a certain value, the switching circuit is turned on immediately and the main power supply supplies all of the load power again. However, it has the effect of causing the microcomputer to run out of control and memory to disappear.
It is possible to introduce microcomputers with peace of mind. Furthermore, if the test is performed by connecting a pseudo load resistor when the actual load is light, it becomes possible to test the standby power supply under the maximum load. Furthermore, by controlling the switching circuit on and off through its active range, it prevents the load voltage from dropping more than expected due to delays in the operation of the voltage detection circuit and switching circuit, and prevents the generation of excessive noise. It is believed that it is possible to carry out a more crush-free shearing test.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing one embodiment of the present invention, and FIG. 2 is a block diagram showing another embodiment of the present invention. In the figure, 1...DC-DC converter, 2...
Diode, 3... Switching circuit, 4... Voltage detection circuit, 5... Gate, 6... Operation switch for testing, 7... Bus bar, End... Capacitor, 1o... Transformer, ] 1... Rectifier smoothing circuit, 12... Charging circuit, 13... Constant voltage circuit, 14... Second diode, 15... Relay, 16... Normally closed contact of relay, 1
7... Pseudo load resistance, 18... Second switching circuit, 19... Resistor, 20... Capacitor, 21...
... Flip-flop, 22... Backup power supply abnormality display circuit, E, ... Main power supply, E, ... Backup power supply. Applicant Nittan Co., Ltd. Representative Patent Attorney Mr. Sumi 1) Toshimune (and 1 other person 2) Figure 1

Claims (1)

[Claims] (1) A standby power supply test circuit VC which is connected in parallel to the load via a diode and which tests a standby power supply that supplies load VC power in the event of a failure of the main power supply with an actual load; a voltage detection circuit that detects that the voltage is higher than the voltage;
A manual operation switch that closes during the test, a gate that is opened by the output of the voltage detection circuit, and an output signal of the operation switch that is inserted into the output circuit of the main power source and that normally connects the main power source to the load, through which the output signal of the operation switch is input. A standby power supply test circuit comprising: a switching circuit that is opened when the circuit is open; (2. In the standby power supply test circuit according to claim 1), a constant voltage circuit straddle step-down circuit inserted between the output of the standby power supply and the @recorder f-ode; The relay includes a relay circuit connected to the output side of the switching circuit, and a second diode for preventing loopage inserted between a connection point between the relay circuit and the switching element and a load. A normally closed contact is connected between the output of the standby power source and the load. (3) In the standby power supply test circuit described in claim 1 or /ri 2nd ode, a series connection circuit of a pseudo load and a second switching circuit is connected in parallel to nine loads, and The switching circuit is turned on by the output of the gate. (4) In the preliminary @bottom test circuit according to claim 1, 2, or 3, the output K of the gate circuit
fp branch circuit is connected, and the output of the prayer branch circuit is used as a control input of the switching circuit and/or a second switching circuit, and the switching circuit and/or the second switching circuit is controlled to be turned on and off via an active range. characterized by.