The industrial engineer at your plant bought a light meter a few years ago. Whenever a line is redesigned or a layout changed, he wants the lights moved a bit to get the desired light readings.
Now he’s presented you with a problem. He says the lighting has been deteriorating. “I get fewer lumens every time. Instead of moving a given fixture a little bit, we now have to position it exactly. And we’re adding task lighting.”
On his workstation, he shows you a trending analysis of the readings. Then he explains his methodology. There’s no doubt about the lumens decline. How can you figure out what’s going on?
To isolate the problem, try a new fixture in place of an existing one. See an improvement? All that moving of fixtures means people have been handling them. Look at the shades to see if they’ve been adjusted incorrectly, and look at the lenses to see if they’re smudged. Rather than replacing fixtures, cleaning and adjusting them may solve the problem.
No improvement from that trial replacement? Check the voltage at a few fixtures. If it’s lower than at the supply transformer:
- Conduct insulation resistance testing on the wiring.
- Test connections with an AC resistance tester.
- Visually inspect each neutral wire; if it’s discolored, replace it with a larger one.
Still have low light? Use your power analyzer on the branch circuits.
