How Often Should You Test Emergency Lighting Equipment?

Emergency lighting is one of the most important aspects of any building. Emergency lighting ensures that should a power outage occur, occupants will have light to safely exit the building. There are many reasons why you may need emergency lights in your facility: fire drills and evacuations, power outages, or as an alternative to natural light – like when offices are located on lower levels with no windows. Testing your emergency lights is crucial for safety purposes; however, it can be time-consuming and expensive if done often. This blog post will discuss how often to test emergency lighting equipment in order to maintain safety standards without spending too much money or taking up too much time.

The Best Time to Test, and How Often You Should Be Checking Your Equipment

Standard testing can occur during on or off-hours. A typical lighting inverter test will result in manually putting the system into its physical maintenance bypass. Checking overall components, flow of power, the battery system, and its connections.

An actual performance test may be done after hours so that the system can be tested by cutting power and physically witnessing the operation and duration of the runtime of the lighting inverter system. 

A procedure document (MOP “Methods of Procedures” or Bulletin) is required for all computer room and support environment designated work for most facilities. Attention is directed to IEEE and UL 924 standards while testing equipment.

Switching tags can also be used to validate that electrical or mechanical equipment is properly configured to support the planned activity, leaving a documented date of procedure behind on the equipment.

A Central Lighting Inverter Maintenance Checklist

  1. Complete visual inspection of the unit (circuit boards and cable connections)
  2. Check all displays, LED / LCD indicators
  3. Measure input volts and currents
  4. Check all monitor and control voltages. Calibrate if necessary.
  5. Clean exterior of unit
  6. Complete visual inspection on wiring harness and components to identify discoloration / hot spots
  7. Check for DC capacitor vent caps that have extruded more than 1/8″ (if applicable).
  8. Measure and record harmonic trap filter currents (if applicable).
  9. Check the inverter and rectifier snubbers for burned or broken wires.
  10. Check all nuts, bolts, screws, and connectors for tightness and heat discoloration.
  11. Check fuses on the DC capacitor deck for continuity (if applicable).
  12. With customer approval, perform an operational test of the system, including unit transfer and battery discharge.
  13. Calibrate and record all electronics to system specifications.
  14. Check or perform Engineering Field Change Notices (FCN) as necessary.
  15. Measure and record all low-voltage power supply levels.
  16. Record phase-to-phase input voltage and currents.
  17. Review system performance with customer to address any questions and to schedule any repairs.

How Often do I test a Central Lighting Inverter?

An Emergency Lighting Inverter will require testing on a quarterly basis.

The battery components of an emergency lighting system require a test so that the minimum 90-minute runtime requirement under UL 924 is met and can be performed.  Degraded batteries, battery float voltages, and physical characteristics change with batteries quite frequently.

Can I Use Lithium Ion Batteries for a Lighting Inverter?

At this point, the technology of lithium-ion batteries does not provide the long duration runtime required by UL 924 Standards. Lithium-ion UPS systems and UL 924 Approved Central Lighting Inverter systems require 90 minutes of lighting for emergency egress. Lithium-ion battery systems right now provide short burst durations. This technology will, however, catch up in the short future. 

How Much Does Testing Cost?

A typical Central Lighting inverter power system with batteries is determined by its electrical components and batteries. A smaller Lighting inverter in the 500VA-5kVA range will cost several hundred to $1000 per year to test and maintain. Larger, full building systems 5kVA to 50kVA will range from $2000-$5000 per year. Very large systems for complexes and large electrical systems are proportionate to their size.  

Looking for Lighting Inverter Maintenance Help?

You can receive quotes for lighting inverter maintenance at For questions on systems and service please call 844-501-1887.

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