The daily maintenance of power frequency online UPS is crucial for ensuring its stable operation and extending its service life. The following are key points to pay attention to in daily maintenance, covering multiple dimensions:
1、 Environment and hardware inspection
1. Monitoring of operating environment
Temperature and humidity:
The suitable operating temperature for UPS is 15 ℃~25 ℃, and the humidity is controlled at 40%~60% (to avoid equipment short circuits or static electricity caused by humidity or dryness).
▶ If the ambient temperature is too high, it will accelerate battery aging; When the humidity is too high, the dehumidification device needs to be turned on.
Ventilation and dust prevention:
Ensure that there are no obstructions around the UPS, keep the ventilation holes unobstructed (at least 30cm away from the wall), regularly clean the dust on the equipment surface and fan (using compressed air blowing), and prevent dust accumulation from affecting heat dissipation.
Power input:
Check whether the input voltage (such as 380V/220V) and frequency (50Hz) are stable, and the fluctuation range should be within the UPS rated allowable range (usually ± 10% for voltage and ± 5% for frequency), to avoid frequent power outages or voltage fluctuations.
2. Hardware appearance inspection
Shell and indicator light:
Check whether the UPS casing is deformed or damaged, and whether the panel indicator lights are normal (such as running lights, battery lights, fault lights, etc.). If there is abnormal flashing or constant lighting (such as a red fault light), the cause should be immediately investigated.
Connecting wires and terminals:
Check whether the input/output cables and battery connection wires are loose, aged, or overheated (whether the touch terminals are hot), and there should be no oxidation or corrosion at the terminal connections (Vaseline protection can be applied).
Fan operation:
Monitor the sound of the fan running normally (without noise or lag) when turning on. If the fan stops running or makes abnormal noise, it may cause the device to overheat and needs to be replaced in a timely manner.
2、 Battery system maintenance
1. Battery pack status check
Voltage and Capacity:
Regularly measure the voltage of a single battery with a multimeter (such as a 12V battery with a normal voltage of about 12.6V~13.2V). If the voltage is lower than 12V, there may be battery aging or depletion; Use a battery tester to evaluate the overall capacity (recommended once every quarter), and consider replacing if the capacity is below 80% of the rated value.
Appearance and Temperature:
Check whether the battery casing is bulging or leaking, whether the terminals are rusted, and whether the surface temperature of the battery is uniform (the temperature during operation should not exceed 40 ℃, and if there is local overheating, it may cause internal short circuit).
Battery connection:
Ensure that the series/parallel connections of the battery pack are secure and the connections are not loose (can be tightened with a torque wrench according to specifications), to avoid poor contact causing voltage drop or heating.
2. Battery charging and discharging management
Floating voltage setting:
The default float charging voltage of UPS should comply with the battery type (such as valve regulated lead-acid batteries with a float charging voltage of about 2.23V/cell), to avoid overcharging (causing water loss) or undercharging (causing sulfurization).
Regular discharge test:
Perform a load discharge test every 3-6 months (discharge to 30%~50% of rated capacity), simulate a power outage scenario, and check the response time, battery life, and charging recovery function of UPS switching to battery mode.
▶ Long term full charge storage can lead to battery "passivation", and discharge testing can activate active substances.
3、 Function and Load Management
1. Load monitoring
Capacity matching:
It is recommended to control the UPS load rate between 60% and 80% (to avoid long-term full or empty load). Overloading can cause the inverter to overheat and even trigger a protective shutdown.
▶ When adding new loads, it is necessary to calculate the total power (including peak power) to ensure that it does not exceed the rated capacity of the UPS.
Load type:
Avoid connecting impactful loads (such as motors, air conditioners) or non-linear loads (such as switching power supplies), as these loads can generate harmonics and affect UPS performance (can be paired with voltage regulators or filtering devices).
2. Switching and protection function testing
Switching between mains and battery modes:
Manually disconnect the mains input and observe whether the UPS immediately switches to battery mode, and whether the output voltage and frequency are stable (switching time should be less than 10ms, with no obvious inductance loss).
Fault protection test:
Simulate overload, short circuit and other faults, check whether the UPS can trigger protection in a timely manner (such as sound and light alarm, bypass switching), and whether it can recover normally after troubleshooting.
4、 Recording and troubleshooting
1. Running data recording
Establish maintenance logs to record daily input/output voltage, current, load rate, battery voltage, ambient temperature, and other data for comparative analysis of trends (such as contacting the power department when voltage fluctuations are frequent).
Record the on/off time, maintenance content (such as dust removal and battery testing), and abnormal events (such as power outages and alarms) to provide a basis for subsequent maintenance.
2. Common fault handling
Battery failure: If the voltage of a single battery is too low or leaks, it is necessary to replace it with a battery of the same model in a timely manner to avoid affecting the overall performance of the group; When replacing the battery, disconnect the UPS power supply to ensure safety.
Inverter malfunction: If an "inverter abnormality" alarm occurs, check whether the cooling fan and power module are damaged, or contact a professional engineer to inspect the drive circuit.
Bypass mode operation: If the UPS is in a bypass state for a long time, there may be abnormal mains power or internal faults. It is necessary to first restore mains power and then check the internal components of the UPS (such as static switches and control boards).
5、 Suggestions for safety and professional maintenance
Safe operation:
Before maintenance, disconnect the UPS input/output switch and wait for the capacitor to discharge (at least 5 minutes) to avoid electric shock; Do not disassemble batteries or circuit boards while they are live.
Professional maintenance cycle:
Every six months: Professional personnel conduct internal dust removal, circuit board solder joint inspection, and parameter calibration (such as float voltage and switching time).
Every year: comprehensively inspect the performance of inverters and rectifiers, replace aging capacitors, fans and other vulnerable parts.
Backup battery management:
Backup batteries should be stored in a dry, cool place and charged regularly (once every 3 months) to avoid long-term storage that may result in scrap.
Through systematic daily maintenance, the stability of power frequency online UPS can be effectively improved, reducing the impact of sudden power outages on critical equipment such as servers and medical instruments, while also lowering operation and maintenance costs. If encountering complex faults, it is recommended to contact the UPS manufacturer or professional maintenance team for handling to avoid disassembling and causing secondary damage.
