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Cross Connection at Electrical Service Meter

Cross Connection at Electrical Service Meter

Cross Connection at Electrical Service Meter

(OP)
Hello All,

I am assessing an over voltage situation where a home owner's tv's, stereo equipment etc. failed and overheated when a temporary above ground electrical service cable, connected from the utility's transformer to the service meter, was energized. (Due to a problem with the existing underground service cable which required repairs, the above ground cable was used to temporarily supply power to the dwelling while allowing for repairs to the underground cable).

As the temporary cable was energized, various electric and electronic devices in the dwelling overheated with smoke noted to be emanating from tv's!

Everyone knows of the potential "floating neutral" condition and related voltage imbalances that could occur in 120V circuits. But my question is the following:

If one of the incoming line conductors in the temporary cable was mistakenly connected to the neutral terminal in the service meter, with the incoming neutral conductor connected to one of the line terminals in the meter, could this have applied 240 Volts to various 120V circuits in the dwelling, leading to the overheating/failure? Thanks in advance!

RE: Cross Connection at Electrical Service Meter

Sure, it could have.

RE: Cross Connection at Electrical Service Meter

The last time I saw it done (neutral and line interchanged) a lot of things smoked. Also, an open neutral will smoke a lot of things.
Same customer both times. Both times, before the agreed time for me to arrive, he found someone cheaper. The first one opened the neutral and smoked a lot of electronics. A few months later, after he had replaced all of his blown electronic toys, he pulled the same stunt again and this guy interchanged a hot and neutral. Then the customer got mad at me!!! I didn't have any sympathy or patience with him at all.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Cross Connection at Electrical Service Meter

Saw this happen more than a few times when I was working as a service technician supporting rental generators, especially on model homes at large development projects.

Temporary power misapplied can sure cause a lot of damage.

RE: Cross Connection at Electrical Service Meter

Had an electrician buddy who sent a worker out to a trailer park.  He promptly dropped the neutral... Guy had to buy a lot of refrigerators.

Keith Cress
kcress - http://www.flaminsystems.com

RE: Cross Connection at Electrical Service Meter

 
Another possibility might have been a poor neutral connection in an otherwise OK setup, allowing a "shifted" neutral.
   

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