1. The UPS output is normal when there is mains, and the buzzer sounds when there is no mains, no output.
Fault analysis: Judging from the phenomenon that the battery and the inverter are partially faulty, the following procedures can be checked:
——Check the battery voltage to see if the battery is not fully charged. If the battery is not fully charged, check whether the battery itself is faulty or the charging circuit is faulty.
——If the battery working voltage is normal, check whether the inverter drive circuit works normally. If the output of the drive circuit is normal, the inverter is damaged.
——If the inverter drive circuit is not working properly, check the waveform generation circuit for the presence of the PWM control signal output. If there is a control signal output, the fault is in the inverter drive circuit.
——If the waveform generation circuit has no PWM control signal output, check whether the output is blocked due to the protection circuit operation, and if so, find the protection reason;
——If the protection circuit is not working and the working voltage is normal, and the waveform generation circuit has no PWM waveform output, the waveform generation circuit is damaged.
The above troubleshooting sequence can also be reversed, sometimes finding faults faster.
2. The battery voltage is low, but the battery voltage is still not charged when the battery is turned on for more than ten hours.
Fault analysis: If the battery or charging circuit is faulty from the phenomenon, you can check the following steps:
——Check if the input and output voltage of the charging circuit is normal;
——If the charging circuit input is normal, the output is abnormal, disconnect the battery
Retest, if it is still not normal, the charging circuit is faulty;
——If the input and output of the charging circuit are normal after disconnecting the battery, it means that the battery has been damaged due to long-term uncharged, over-discharged or has reached the end of life.
3. The inverter power stage is damaged by a pair of power amplifier transistors. After replacing the same type of transistor, the reason why the running is burned for a while is that the current is too large, and the cause of excessive current is:
- Overcurrent protection is ineffective. When an overcurrent occurs in the inverter output, the overcurrent protection circuit does not function;
—— Pulse width modulation (PWM) component failure, the output of the two complementary waveforms is asymmetrical, one conduction time is long, and the other conduction time is short, so that the two arms work unbalanced, even the two arms are simultaneously turned on, resulting in two Tube damage;
——The power tube parameters differ greatly. At this time, even if the input symmetrical waveform is input, the output will be asymmetrical. The waveform will be biased by the output transformer, that is, the magnetic flux is unbalanced. The accumulation will cause the transformer to saturate and the current will suddenly increase and burn out. The power tube, while one burned out and the other burned out.
4. After the UPS is turned on, there is no display on the panel, and the UPS does not work.
Fault analysis: Judging from the fault phenomenon, its fault is in the mains input, battery and mains detection part and battery voltage detection loop:
- check if the mains input fuse is burnt;
——If the mains input fuse is intact, check whether the battery insurance is burnt, because some UPS will turn off all output and display of the UPS when the self-test does not have the battery voltage;
——If the battery insurance is in good condition, check whether the mains detection circuit works normally. If the mains detection circuit is not working properly and the UPS does not have the mains start function, the UPS will also turn off all output and display.
——If the city detection circuit works normally, check if the battery voltage detection circuit is normal.
5. In the case of access to the mains, each time the UPS is turned on, the relay repeatedly hears the action. The UPS panel battery voltage is too low and the buzzer sounds long.
According to the above fault phenomenon, it can be judged that the fault is caused by the battery voltage being too low, which causes the UPS to start unsuccessfully. Remove the battery and perform equalization charging (all batteries are charged in parallel). If it is still unsuccessful, only replace the battery.
6. When a backup UPS has utility power, it works normally. When there is no mains, the inverter has output, but the output voltage is low, and the transformer emits loud noise.
Fault analysis: The output of the inverter indicates that the final drive circuit is basically normal. The noise of the transformer indicates that the two arms of the push-pull circuit are asymmetrical. The detection steps are as follows:
- check if the power is normal;
——If the power is normal, check whether the output signal of the pulse width output circuit is normal;
——If the output of the pulse width output circuit is normal, check if the output of the drive circuit is normal.
7. When the mains supply is normal, the UPS is turned on, the working indicator of the inverter flashes, and the buzzer sounds intermittent. The UPS can only work in the inverter state and cannot be switched to the mains working state.
Fault analysis: The inverter power supply cannot be converted to the mains power supply, indicating that the inverter power supply has failed to the mains power supply conversion part.
——Whether the mains input fuse is damaged;
——If the mains input fuse is intact, check whether the output of the mains rectifier filter circuit is normal;
——If the output of the commercial rectification and filtering circuit is normal, check whether the mains detection circuit is normal;
——If the mains detection circuit is normal, check whether the output of the inverter power supply to the mains supply conversion control is normal.
8. Backup UPS When the load is close to full load, the mains supply is normal, and the battery fuse is blown when the battery is powered.
Fault analysis: The battery fuse is blown, indicating that the battery supply current is too large. The detection steps are as follows:
- whether the inverter is broken down;
- whether the battery voltage is too low;
——If the battery voltage is too low, check if the battery charging circuit is normal;
——If the battery charging circuit is normal, check whether the battery voltage detection circuit works normally.
9, UPS can only be powered by the mains and can not be converted to inverter power.
Fault analysis: The power supply to the inverter cannot be converted, indicating that the mains fails to the inverter power supply conversion.
——Whether the battery voltage is too low, and the battery fuse is intact;
——If the battery is partially normal, check if the battery voltage detection circuit is normal;
If the battery voltage detection circuit is normal, check whether the utility power supply to the inverter power supply conversion control output is normal.
Two cases of UPS uninterruptible power supply repair
The protection brand MUS1000L UPS is a kind of power supply equipment used by many users, and its output sine wave and mains
Synchronization, small distortion coefficient, stable and reliable performance, is an ideal long-term backup power supply for microcomputers. The following describes two cases of failure
Exclusion methods are for reference.
Fault phenomenon: 1. No load is energized, no power can be transferred to the mains, no inverter, no operation of the machine, no buzzer sounds.
Inspection analysis and processing results: First check the exchange insurance, battery insurance, are normal. Check the battery voltage again, the measured voltage is 48V, and the battery is normal. Therefore, it is concluded that the fault is in the control section. According to the working principle of the backup UPS, in the case of no mains input, the UPS outputs 220V voltage from the control circuit and the battery inverter, and the buzzer keeps alarming. This symptom indicates that the control circuit is not working, and the operating voltage of the control circuit is provided by the battery (as shown in the block schematic below). After inspection, it was found that the three-terminal regulator block "7812" was damaged. After replacing the new three-terminal regulator block "7812", the mains supply was turned on normally, and the inverter was normal after the power was cut off.
Fault phenomenon 2: The utility power is working normally, and the backup working time with normal load is seriously insufficient.
Detection and analysis: From the analysis of fault phenomena, the fault may have: 1. The battery voltage is too low, not fully charged. 2. The inverter control circuit is faulty. 3. Some batteries are damaged. 4. The charger circuit is faulty. 5. The output plugs in the moisture and intrusion caused by moisture intrusion. First check: 1. Clear the output connector to eliminate leakage. 2. Charge the UPS for a long time, and the power-on fault still exists after charging. 3. Use a multimeter to check the battery pack voltage, which is normal for 48V. 4. Check the charging circuit, normal. 5. Check the inverter control loop, normal. 6. Check the electrical performance of the battery with a multimeter and an ammeter according to the following figure. It is found that the electrical performance of the battery pack is degraded, which is caused by the increase of the internal resistance of the battery. The battery voltage was measured at 48V without a 50Ω resistor. After the resistor is connected, the current is 800mA, and the voltage across the resistor is 40V. The test data shows that the internal resistance of the battery increases, that is, the power consumption of the 8V voltage drop on the internal resistance is 6.4W. If the internal resistance of the battery increases and the power supply time is 30 minutes, the battery performance is degraded.
Processing result: Replace the battery, normal after booting, can reach the long backup time of the UPS. The cost of the battery is very high, accounting for more than 30% of the total cost of the UPS. Therefore, in order to save money, the battery charger with some performance degradation can be forcibly charged, and the charging is successful and can still be used. This fault is sometimes caused by damage to the inverter control circuit cooling fan. Please pay attention when maintaining the user.
MT series simple troubleshooting
Question 1: Why is the mains power not interrupted, but the UPS will flash green and the buzzer will beep every 4 seconds?
A: First check if the circuit breaker is bounced off? If it has been bounced, you can press it to reset it. Second, when the mains fluctuates and exceeds the input specifications of the UPS, the UPS will automatically switch to battery power (the green light flashes and the buzzer sounds every 4 seconds). When the mains returns to normal, the UPS will automatically jump back to the mains supply. After the UPS is transferred to the backup power supply, please save the personal computer and other equipment in time or other power failure emergency treatment. After the utility power returns to normal, please turn on the UPS in time to charge the battery.
Question 2: Why is the UPS interrupting the output when the mains supply is interrupted, causing the computer to crash? A: When the battery ages, it will cause insufficient power storage or the battery has been discharged due to power failure, resulting in insufficient recharging time (charging time should be more than 10 hours, to recharge to 90% capacity), the above conditions will make UPS Unable to back up power or insufficient power supply time. If the battery ages, please replace it.
Question 3: Why is there no power outage, the UPS frequently switches between the mains/battery status (green light/flash, buzzer not called/call)? Answer: 1. When the mains voltage fluctuation is abnormal and the UPS mains switching voltage is reached, it will act. This is the normal protection action of the UPS. 2. The UPS output is connected to a load such as a printer that has a large starting current, and the instantaneous high current when the printer is turned on causes the UPS to malfunction. Please change the unimportant equipment such as the printer from the UPS to the mains socket.
Question 4: The MTUPS green light is on, the red light is flashing, and the buzzer is called for 1 second and 2 seconds. What should I do? A: The UPS is overloaded. Please remove some of the load before using it.
Question 5: MTUPS
The red light flashes, and the buzzer is called for 2 seconds. What should I do? A: The battery is deeply discharged. Please turn off the load and UPS immediately, and then turn it on again when the utility power returns to normal, and continue to charge more than 10H.
Question 6: The MTUPS green light is on, the red light is flashing, and the buzzer is called for 2 seconds 3, what should I do? A: The UPS charging circuit is faulty, or the battery is damaged and needs to be replaced.
Question 7: The red light of MTUPS is on, the buzzer sounds long, what should I do?
Answer: 1. If the output is seriously overloaded or short-circuited, all loads should be removed and restarted. If the UPS returns to normal, the load is faulty. Please check the load status yourself. 2. Internal fault of UPS.
Fault phenomenon 1: When the mains supply of the regulated power supply is normal, there is output during the inverter, but the output voltage is as high as 275V.
Analysis and maintenance: According to the working principle of the regulated power supply, the above phenomenon occurs only when the high voltage protection circuit of the power supply and the mains voltage stabilization circuit are faulty. After the power supply output voltage is sampled, rectified, and filtered by T2, it is applied to pins 8 and 9 of voltage comparator U7, and then connected to the reference voltage terminal. Only when the voltage of pin 8 of comparator U7 is higher than the voltage of pin 9, pin 4 will jump to a low level output, thereby controlling the protection voltage action. The following tests are performed in two steps:
1, the detection of the city power regulator
It can be seen from the physical map that the magnitude of the mains voltage depends on the pull-in state of the relays S3 to S8. Firstly, the multimeter is used to detect one by one, and it is found that the coil of the relay S3 has been blown, so the S3 does not pick up, so that the 220V mains voltage is completely added between the third and fourth taps of the T3, resulting in a high output voltage. Replace T3, start up and troubleshoot. In actual work, considering that the regulated power supply is directly connected to the AC voltage regulator, and the relay of the same specification can be replaced, the first and third of the S3 can be shorted.
2. Detection of high voltage protection circuit
First, the voltage of the 8-pin voltage of the voltage comparator U7 is 2.35v and the voltage of the 9-pin is 2.25v. The high-voltage protection circuit does not start. Carefully review each component of the high voltage protection circuit one by one without any faults. Adjust the potentiometer RP8 appropriately. When the value is lowered to a certain value (decrease), the high voltage protection circuit suddenly starts normally. It can be seen that the voltage of the high voltage protection circuit of the power supply is too high and needs to be readjusted. Connect the input of the power supply to the AC voltage regulator and the output terminal to the voltmeter. Then slowly increase the voltage of the regulator from 175v to 250v and record that the maximum output voltage is 230v during this process. When the output voltage is 235v, slowly adjust the potentiometer RP8 in the counterclockwise direction until the high voltage protection circuit is started. Note that when the high voltage protection circuit fails and the output voltage is 220v ± 5%, it cannot be observed by the naked eye. Therefore, it is necessary to regularly check whether the high voltage protection circuit is normal during use.
Fault phenomenon 2: When the power is off, the inverter does not work.
Analysis and maintenance: According to the analysis of the fault phenomenon, the fault is caused by the battery voltage being too low. Open the cover, remove it and charge it, and troubleshoot. After a period of time, the fault remains, so the charging circuit is suspected to be faulty. Use the multimeter voltage file to detect the three-terminal adjustable voltage regulator block LM317 in the charging circuit. The input voltage is normal, but the output voltage is only 14.3v, and there is no response after re-adjustment. Therefore, it is judged that the LM317 is damaged. Replace it, restart, remove the battery, and adjust the charging voltage to 27v, the fault will be eliminated. Symptom 3: When the mains is interrupted, the inverter does not work, and the red indicator light is on.
Analysis and maintenance: According to the fault phenomenon, the fault is caused by the battery voltage being too low. Open the cover and measure that the voltage across the battery is only 16.8v. After the listing, the voltage at both ends of the battery does not change, indicating that the fault occurred on the charging circuit. The working principle of the charging circuit is: when the utility power works normally, the main transformer T3 outputs an AC voltage of 25V, and the output voltage of the first and second pin contacts of the S2 relay is rectified by the B1 bridge, and the C21 and C22 are filtered to output 34v. DC voltage. After it is sent to the adjustable regulator U8 (MG317T), the battery is charged.
The DC voltage across C21 is measured by a multimeter, indicating that the regulated power supply fault occurs after the filter circuit. When measuring the output pin of MG317T, it is found that the output voltage is only 110v, check the output load is normal, adjust the output voltage of VR3 does not change, this indicates that U8 is damaged. Replace U8 with the same model MG317T, disconnect the battery, adjust VR3, so that the U8 output voltage is stable at around 28v. Start the test run and troubleshoot.
Symptom of power supply failure: When the power is off, the inverter does not work.
Analysis and maintenance: According to the analysis of the fault phenomenon, the fault is caused by the battery voltage being too low. Open the cover, remove it and charge it, and troubleshoot. After a period of time, the fault remains, so the charging circuit is suspected to be faulty. Use the multimeter voltage file to detect the three-terminal adjustable voltage regulator block LM317 in the charging circuit. The input voltage is normal, but the output voltage is only 14.3v, and there is no response after re-adjustment. Therefore, it is judged that the LM317 is damaged. Replace it, restart, remove the battery, and adjust the charging voltage to 27v, the fault will be eliminated.
Symptom of power supply failure: When the mains is interrupted, the inverter does not work, and the red indicator light is on.
Analysis and maintenance: According to the fault phenomenon, the fault is caused by the battery voltage being too low. Open the cover and measure that the voltage across the battery is only 16.8v. After the listing, the voltage at both ends of the battery does not change, indicating that the fault occurred on the charging circuit. The working principle of the charging circuit is: when the utility power works normally, the main transformer T3 outputs an AC voltage of 25V, and the output voltage of the first and second pin contacts of the S2 relay is rectified by the B1 bridge, and the C21 and C22 are filtered to output 34v. DC voltage. After it is sent to the adjustable regulator U8 (MG317T), the battery is charged.
Using a multimeter to measure the regulated power supply, the DC voltage across C21 is normal, indicating that the fault occurred after the filter circuit. When measuring the output pin of MG317T, it is found that the output voltage is only 110v, check the output load is normal, adjust the output voltage of VR3 does not change, this indicates that U8 is damaged. Replace U8 with the same model MG317T, disconnect the battery, adjust VR3, so that the U8 output voltage is stable at around 28v. Start the test run and troubleshoot.
Three special 500VAUPS regulated power supply fault repair four
Fault phenomenon 1: The mains supply is normal, there is output when inverter, but the output voltage is high, rising to 265V.
Fault analysis and maintenance: According to the working principle of UPS power supply, the above faults will only occur when the high voltage protection circuit of the power supply and the mains voltage regulator circuit are faulty. It can be seen from the circuit diagram 1 that the power supply output voltage is sampled, rectified, and filtered by T2, and then applied to the 8-pin and 9-pin of the voltage comparator U7, and then connected to the reference voltage terminal. Only when the voltage of pin 8 is higher than the voltage of pin 9, the output pin 4 will jump to a low level, thereby controlling the protection circuit. The following two steps are tested:
1. Detection of high voltage protection circuit
First, the voltage of the 8-pin of the voltage comparator U7 is 2.35V and the voltage of the 9-pin is 2.25V with a multimeter. At this time, the high-voltage protection circuit does not start. Carefully review each device of the high voltage protection circuit one by one without failure. Adjust the potentiometer RP8 appropriately. When it is lowered to a certain value, the high voltage protection circuit starts. It can be seen that the voltage of the high voltage protection circuit of the power supply is too high and needs to be readjusted. Connect the input of the power supply to the AC voltage regulator and the output terminal to the voltmeter. The voltage of the AC voltage regulator is then slowly increased from 175V to 250V, during which the U output max = 230V. The voltage of the AC voltage regulator is then slowly increased from 250V and it is found that the U output rises as the U input increases. When the U output = 235V, slowly adjust the potentiometer RP8 in the counterclockwise direction, when the high voltage protection circuit is just started.
2. Detection of mains voltage regulator circuit
As can be seen from the circuit diagram 2, the level of the mains voltage depends on the state of the pull-in of the relays S3 to S8. Checking the circuit diagram one by one, it is found that the coil of the relay S3 has been blown, and the S3 is not sucked, so that the 220V mains voltage is completely added between the third and fourth plugs of the T3, resulting in a high output voltage. Replace T3, start up and troubleshoot. In actual work, it is considered that the regulated power supply is connected to the AC voltage regulator, and the relay of the same specification can be replaced, so the first and third feet of the S3 can be shorted.
Fault phenomenon 2: The inverter does not work when the power is off.
Fault analysis and maintenance: According to the analysis of the fault phenomenon, the fault is caused by the battery voltage being too low. Open the cover, remove it and charge it, and troubleshoot. However, after a period of use, the fault remains. Therefore, it is suspected that the charging circuit is faulty. Use a multimeter to detect the three-terminal adjustable voltage regulator block LM317 in the charging circuit. The input voltage is normal, but the output voltage is only +14.3V, and there is no response after repeated adjustment. Therefore, it is judged that the LM317 is damaged. Replace it, restart, remove the battery, adjust the charging voltage to 27V, and troubleshoot.
Fault phenomenon 3: When the utility power is interrupted, the inverter does not work, and the red indicator light is on.
Fault analysis and maintenance: It is known from the fault phenomenon that the fault is caused by the battery voltage being too low. Open the cover and measure that the voltage across the battery is only 16.8V. After the listing, the voltage at both ends does not change, indicating that the fault is in the charging circuit. The working principle of the charging circuit is: when the mains works, the main transformer T3 outputs 25V AC voltage, after the first and second pin contacts of the S2 relay, and then the B1 bridge rectification, C21, C22 filtering and output 34V DC voltage. . Then send it to the adjustable regulator U8 (MG317T) to regulate the battery.
Using a multimeter, the DC voltage across C21 is normal, indicating that the fault is behind the filter circuit. When measuring the output pin of MG317T, it is found that the output voltage is only 10V, check the output load is normal, adjust VR3, the output voltage does not change, indicating that U8 is damaged. Replace U8 with the same model MG317T, disconnect the battery, adjust VR3, so that the U8 output voltage is stable at around 28V. Start the test run and troubleshoot.
Symptom 4: When the mains is interrupted, the inverter does not work and the buzzer sounds long.
Fault analysis and maintenance: The buzzer sounds long, indicating that the conversion control circuit of the regulated power supply is normal, and the inverter does not work due to the action of the protection circuit. Use a multimeter to check that the battery voltage is normal, indicating that the fault is in the inverter circuit. The inverter circuit of the machine is composed of pulse width modulator U1 (SG3524), sampling transformer T2, push tube Q5, Q6 and inverter tubes Q17, Q18 and so on. First measure the 10th pin of the pulse width modulator U1 (SG3524) to see if it is locked (high level when locked), and then measure the resistance of the inverter tube Q17, Q18 to ground when it is static. Normal data: When the black pen is grounded, the resistance values ​​of the e, b, and c poles of Q17 and Q18 are 3.2KΩ, 3.8KΩ, and 0 respectively; when the red pen is grounded, the e poles of Q17 and Q18, b The pole and c pole to ground resistance values ​​are 5.5KΩ, 6.5KΩ, and 0, respectively. The measured values ​​of the e, b, and c poles of Q17 and Q18 are only 100Ω with a multimeter. It can be confirmed that the inverter tubes Q17, Q18 and the push tubes Q5 and Q6 have burned out. Replace it, troubleshoot.
In the process of handling the company's UPS maintenance, I found that most of the UPS power supply failures are caused by factors such as battery, mains, use environment and usage methods. A considerable part of the UPS itself has not failed. So list these faults for your reference.
Failure caused by utility power
Grid interference. If there is a very serious interference air switch tripping in the power grid, such as voltage sinking and other power supply interference, it may cause the UPS to have a power failure. Below we list some of these mains interference. You can install PowerChute
Plus software, through the event record of the software to understand whether there is power interference in the power grid. If you see a lot of such records in the event log, it indicates that there is a serious interference in your mains grid, which will also reduce the battery life. If conditions permit, it is recommended that you replace the mains input or modify the grid. PowerChute
Plus event records can record the mains interference:
UPSonbattery: Deepmomentarysag depth voltage sag
UPSonbattery:Largemomentaryspike depth high voltage pulse
UPSonbattery: Brownout continues to low voltage
UPSonbattery: HighinputLinevoltage high input voltage
UPSonbattery: Smallmomentaryspike mild high voltage pulse
UPSonbattery: Smallmomentarysag mild voltage sag
2. The leakage protector is installed at the input of the UPS. When the UPS is turned on, it will cause the leakage protector to trip. The leakage protector trips and trips. If you need to install the leakage protector, you need to connect the leakage protector to the output line of the UPS.
3. The air switch at the PS input trips. This phenomenon may be caused by the small air switch capacity at the input of the UPS. Because the starting current of the UPS is relatively large, the capacity of the front air switch is required to be large enough.
4. UPS inverter status and online status are frequently converted. First, it may be caused by fluctuations in utility power. Second, this happens if you use a generator.
Solution:
1. Smart-UPS can't cold start leakage switch trip, but it can work normally.
This is an operation method that does not trip the leakage protector trip leakage protector. The correct cold start procedure is: hold down the Test button, and immediately release the “嘀†sound for about 4 seconds, then the UPS can be cold-started. If the time is too long or too short, the UPS will not start cold. It is recommended that you follow this procedure a few more times.
2. The communication between the UPS and the computer is not normal.
This can happen if you have not used APC's original communication line air conditioner to trip.
4. SU5000UXI, SU5000INET, SU5000RMINET input line connection method. These three models are shipped without an input cable, but have dedicated input cable terminals. Input cable connection procedure: Find the terminal block of the UPS input cable (for the SU5000INET, the input cable terminal is in the upper right corner of the UPS back, for the SU5000RMINET in the upper left corner of the UPS back), it is hidden in the cover leakage switch in the cover The cover is fixed by a screw. It is necessary to loosen the screw with a screwdriver and remove the cover to connect the input line.
5. The fan starts frequently when the Smart-UPS works online. This situation is caused by the high temperature inside the UPS. You can install PowerChute.
Plus observes the internal temperature of the UPS, which is usually started when the machine reaches 40 degrees Celsius. This design is to improve the service life and operational reliability of the UPS. There are several types of failures caused by the reservoir problem:
1. The UPS cannot be started. Because the Smart-UPS is activated by DC, the UPS cannot be started when there is no battery, low battery, or battery problems. There are several similar situations below:
Case 1: The newly installed UPS cannot be started.
If the UPS is a SUA1000ICH model, check if the battery connector on the rear panel of the UPS is connected. For a rack-mounted UPS such as the SU3000RMI3U, open the front panel and check if the battery is connected.
Since the new battery will self-discharge during storage, the UPS cannot be started in the low-power state. At this time, you need to connect the UPS to the battery and the mains. Press the Test button on the front panel of the UPS. Although the UPS panel indicator will not light, the UPS will charge the battery. After charging for a period of time, press the Test button and the UPS will start working.
The second case: After the UPS inverter works for a period of time, the UPS cannot start.
Also because the battery is low, you need to charge the battery.
The third case: the battery took about 2 years, the UPS could not be started.
According to the usage of most customers, the battery generally has more or less capacity reduction after two years of use. If the battery does not play a role in delay, it needs to be replaced with a new one.
The fourth situation: the voltage of a single battery is normal, but the UPS cannot be started.
At this time, although the voltage of the single battery is normal, 1. It is probably due to the connection between the battery and the battery or the connection between the battery and the UPS. For example, the connection point is not strong or the connection point is oxidized and always trips. At this point, you need to remove the oxide and reconnect. 2. It may be that the UPS and the battery connection are broken, and if the insurance is broken, you can change the insurance. 3. The connection between the UPS and the battery is very long, very thin or has a connection point in the middle, so a large voltage drop trip switch is generated, which causes the UPS to fail to start.
2. The UPS cannot be turned to the inverter state after the mains power is cut off. Let the UPS work in the mains state, set the multimeter in the voltage range, and connect the test pen to the relay position of the Anderson plug on the back of the UPS. The relay leakage protector trips and directly measures the DC voltage reaching the UPS. At this time, one person observes the multimeter to show that the leakage switch trips, and another person pulls out the input line trip switch of the UPS to observe the display of the multimeter at the moment of power failure. If the voltage value drops a lot of transformers instantaneously
Tripping, indicating that there is a problem with the battery, if you can eliminate the connection problem, and the battery has been used for about two years, you need to consider replacing the battery pack. 3.
The UPS inverter time is short and cannot meet customer requirements. First, the Smart-UPS long-delay model must be set at the beginning of the installation. If the battery parameters are not set, the inverter time will be short.
Second, the battery parameters have been set, but the UPS's inverter time is still very short. You can trip the leakage switch when the UPS low power alarm, measure the battery voltage, if the measured value shows that the battery is indeed in a low state, the electric water heater trips, you need to replace the battery. If the measured value indicates that the battery is not in a low battery state, you will need to check the charge and discharge. Note that in the charge and discharge calibration, the battery must be fully filled with an open trip, and it needs to carry about 50% of the load when discharging.
Third, the PowerChutePlus software is installed, because the default setting of the software is: 5 minutes after the mains interruption, the computer is turned off, so you need to modify the parameters in the software. Other factors: 1.
Smart-UPS often has an overload alarm. Please check if there is a printer connected to the UPS. It is not recommended that you connect the printer to the back of the UPS, because the operating current will suddenly increase when the printer is printing. Many electric kettles will trip, which may cause the UPS to overload and power off. It is also not recommended to connect a power outlet to the back of the UPS, as UPS overload may occur due to a short circuit in the power outlet.Wuxi Motian Signage Co., Ltd , https://www.makesignage.com