Electrical Troubleshooting Quiz, October 4, 2010

In one of the buildings on your campus, workers have been complaining about “the terrible lighting.”

In one of the buildings on your campus, workers have been complaining about “the terrible lighting.” Complaints include excess shadows, low light levels, eye strain, and inability to read box labels without a flashlight. Over the summer, the complaints weren't acted upon because a relamping was scheduled for September. But it's now October, and the complaints persist.

Two facts:

  1. The relamping contractor used the correct replacement lamps, so it's not a wrong lamp issue.
  2. Records show these complaints started a couple of years ago, long after any reconfiguration in lighting design or equipment configuration.
We can see the design matches the application, and the lamps match the specifications. What could be causing this “terrible lighting” problem, and what should you do first?

Before embarking on a lighting redesign as the solution, perform this sequence of steps:

  • Ensure the lampshades are clean and properly adjusted and that lamp lenses are clean and undamaged.
  • Note where the equipment hasn’t been reconfigured but the operators have been (e.g., operator used to stand to the left but now stands to the right). This doesn't account for all complaints, but it may be an issue.
  • Using a power monitor on each branch circuit, look at the waveform (on each phase and the neutral), the voltage level (phase-to-phase, phase-to-ground), power factor, and total harmonics. Fix any power quality issues.
  • Transient voltages or chronic overheating may have damaged conductor insulation. Conduct insulation resistance tests on the conductors and neutrals of each branch circuit.
  • Take lumens readings in an area lit by four fixtures. Then, replace the ballasts and lamps and take new readings. If readings are higher, conduct ballast testing/replacement in all problem areas.
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