Electrical Troubleshooting Quiz, February 4, 2011

You just left a meeting with the plant manager and the controller. They reviewed year-over-year costs with you, using bar graphs generated by the accounting software

You just left a meeting with the plant manager and the controller. They reviewed year-over-year costs with you, using bar graphs generated by the accounting software. For 2010, the category ‘Replacement Purchases, Admin Areas” is six times larger than it was in 2008. A breakout materials list shows most of this went to new electronic ballasts. The plant manager remarked that this was puzzling, because a contractor had been hired in 2009 to do extensive electrical PM work in the administrative areas precisely to lower these kinds of costs.

This project had been commissioned and overseen by the corporate office. You had no hand in it, but now your boss wants you to figure out what’s wrong. Where should you start?

First, commission thermal scans of the distribution panels. If the PM work involved “retorquing” connections, you’ll see many of these connections as hotspots on thermal scans. Replace the hardware; properly clean, assemble, and torque the connections.

Study the documentation for that PM project to see what was done and who did it. Possibly the corporate office took the lowest of three bids, rather than making sure to hire a contractor specifically qualified for PM work. The documentation to review includes:

• Contract specifications (what they were asked to do).
• PM reports (what they say they did).
• Acceptance reports (what they actually did).

Do a walk-through to verify that the documentation matches reality, and record any discrepancies. Maybe there was no problem with this PM work, and the cause is unrelated. Focus on these three basic steps:

1. Look in your power monitor logs for surge or sag events.
2. Conduct a power quality analysis at the branch circuit level; look at power factor, waveform quality, and voltage levels.
3. Inspect the bonding system for integrity issues.