Had a 200 amp main breaker trip on a sunny day in Tampa

I was troubleshooting a new commercial kitchen install when the main panel started humming. Found a loose neutral on the utility side feeding back through the meter base. What's your go-to method for checking utility-side issues before calling the power company?

4 comments

4 Comments

rowan_reed682mo agoMost Upvoted

First thing I do is check voltage at the main lugs with a good meter. If you see a big difference between legs or it's swinging wildly, that's a red flag for a utility problem. A loose neutral on their side can cause all sorts of weird feedback, just like you found. I'll also check the meter base for any signs of heat or corrosion before making the call, it gives them a better place to start.

angela_patel752mo ago

Always blamed the panel until reading this.

ross.christopher2mo ago

Ever had a dim bulb get super bright before calling them?

nathankim4d ago

And once you start seeing this pattern with electrical stuff you realize it's the same everywhere. It's like when your car's check engine light starts flickering right before something major fails or your furnace makes a weird noise right before it dies. The system gives you these warning signs but they're easy to write off as nothing until you learn to connect the dots. With a dim bulb suddenly getting bright it's basically the voltage doing something unstable and that's almost never a small problem. It's the same principle as when you see a single bright LED in a string of lights that are all dim you know there's a short somewhere. Once you've been burned a few times you start paying attention to those little clues because they're usually telling you something bigger is about to happen.