Preventive Maintenance

Preventive Maintenance (PM) is important to ensuring your assets continue to run at peak performance. We recommend annual checks of your equipment beginning the first anniversary date following the manufacture date of the equipment and repeating each year until the asset is removed from service.

We measure and record all critical system parameters including input/output voltages and currents for control circuits, alternate and primary power sources, charger, inverter and static switch output. Abnormal conditions will either be repaired during the PM or noted for remedial action and scheduled for repair after review with the Client. With the Client’s permission, the following functional tests will be performed:

Tested Annually (PM1)

• General - 

  • Test Aux Contact and Shunt Trip circuit in the DC input Breaker by simulating Low DC Voltage Disconnect

  • Test ALL alarm setpoints to insure proper alarming and verify they are set at correct setpoints and time delays

  • Calibrate all voltage and current reading on UPS with True RMS Meter  

  • Verify Free Running Frequency of Inverter and insure it is within +/- 2% of 60HZ to insure proper sync reference to Bypass Source feed, if not adjust frequency

  • Simulate full loss of power to the UPS (Black Plant) and make certain UPS does not transfer and maintains load

  • Test Over Temperature Thermal Couples to make certain Inverter Shuts Down, seamlessly transfers to Bypass and opens DC input breaker

  • Check 480 Input Voltage for balanced currents into Charger Bridge

  • Verify all AC Caps are functioning by taking voltage reading across cap bank

  • Test ripple current on battery to insure less than 5% amp hour rating of battery

  • Any other functional test deemed necessary by the service engineer to verify proper operation

• Battery Chargers - Float/Equalize functions, load share function and alarm functions.

• Inverter/Static Switches - Static Switch automatic transfer function, alarm function, manual bypass transfer function. Verify the proper transfer of the static switch to bypass (no interruption) via the control push buttons and as a simulated Inverter Failure, capture transfer on Oscilloscope to review.

Tested Every Five Years (PM5)

• Includes everything in PM1

• Scheduled Parts Replacement - To assure the optimum performance and reliability of the UPS system, we recommend replacement of critical components, including pilot lights fuses, fans, alarms and relays.

Tested Every 10 Years (PM10)

• Includes everything in PM1

• Scheduled Parts Replacement - To assure the optimum performance and reliability of the UPS system, we recommend replacement of critical components, including pilot lights fuses, fans, alarms and relays.

• Printed Circuit Board Replacement (PCBR) - Replace all printed circuit boards

Additional optional services are available and can be added to preventative maintenance checks:

• Battery Service Test (Cap Test)

• System AC Load Testing (ACL)

• Transformer Replacement (CVT)