UPS & Battery Preventive Maintenance Checklist

In the business world, having a steady power supply is really important. An Uninterruptible Power Supply (UPS) is super helpful when the power goes out. It acts like a shield for important systems. To make sure your UPS keeps working well every day, it’s crucial to follow a simple checklist. Regular maintenance is essential to ensure uninterrupted energy generation and maximize the life span of critical components.  One important aspect of solar power plant maintenance is the upkeep of uninterrupted power supplies (Ups) and batteries.  Below is the comprehensive preventive maintenance checklist for UPS and batteries in a solar power plant.

Importance of PM Checklist in UPS and Battery

1. UPs and batteries are the backbone of solar power plants as they provide essential backup power in case of grid failures or during periods of low sunlight.
2. Effective preventive maintenance ensures reliable backup power and extends the lifespan of costly equipment.

UPS and Battery Maintenance Checklist

Visual Inspection and Contamination Checks:

The first and most important step is to check any signs of liquid contamination, severely affecting performance. Effectively check all batteries and capacitors for any signs of liquid contamination.

Electrical and Performance Checks:

Output Frequency:

 The output frequency of the solar panel should match the standard frequency of the power grid it is connected to. The standard frequency of the grid is 50 HZ or 60 HZ, depending on the country. If the output frequency value deviates from this value, it will indicate an issue with the UPS battery or grid connections. 

For calculating frequency deviation, we can use the below-mentioned formula.

Where: measured frequency is the actual output frequency measured from the UPs.

Visual Inspection of Grounding:

Ensure that the grounding connections are intact and free from corrosion. Proper grounding is necessary for equipment protection and safety.

Check Voltage and Current Readings:

Use a multimeter or power quality analyzer; below are the details of measuring input-output voltages and currents. 

1. Set a multimeter to measure AC voltages.
2. Connect the positive (red) probe to the voltage source and the negative probe (black) to the common or ground terminal.
3. Now, record the voltage readings. For input voltage, measure at the ups systems input terminals; for output voltage, measure at the output terminal.

The same will be the procedure for current measurements.

Power Calculations:

Once you have voltage and current readings, you can calculate power using the following formulas:

1. Apparent Power (VA):

Apparent Power (VA) = Voltage (V) x Current (A)

2. Real Power (W):

Real Power (W) = Voltage (V) x Current (A) x Power Factor (PF)

3. Power Factor (PF):

Power Factor (PF) = Real Power (W) / Apparent Power (VA)

4. Reactive Power (VAR):

Reactive Power (VAR) = √((Apparent Power (VA))^2 – (Real Power (W))^2)

5. Power Factor Angle (θ):

Power Factor Angle (θ) = arccos (Power Factor (PF))

Cleaning and Load Testing:

Regularly clean the UPS equipment enclosures to remove any dust or debris. Dust accumulation can lead to overheating and decreased efficiency.

Off-line Load Test:

Conduct offline load tests to ensure the UPs work well under load conditions.

Electronics and Alarms Inspection:

 Two things need to be checked here:

1. Examining electronic components for signs of wear or damage, repair or replace the damaged equipment.
2. Regularly check systems alarms and LED’s for any error coding or warnings.

Battery Maintenance 

Visual Inspections of Battery:

Visual inspection of the battery includes checking for any signs of leakage. If there is any leakage, then replace the battery.

Voltage Measurements:

Only record the deviation in values of voltage measurements.

1. ICCS and cable connections:
2. Vent cap cleaning :
3. Corrosion checks:

Load Calculations:

Where:

Real power:  actual power being consumed by connected devices and provided by UPs.

UPs rated power: maximum capacity of UPs system.

If the load percentage is, for example, 50 %, then it means that the current devices currently use 50 % of the UPS system-rated capacity.

Conclusion:

Regular preventive maintenance of UPS systems and batteries is crucial to ensure the reliability and longevity of solar power plants. Along with battery maintenance and load calculations, they can provide the design time consideration and the deviations over the years of the values.

Download the sample file of UPS & Battery Preventive Maintenance Checklist

Originally published at futr.energy/knowledge