loose scorched SEC neutral

[John Dirks Jr]

I found this main service panel in a 2002 townhome today. The panel wiring was orderly otherwise but they forgot to tighten the neutral at the main lug. It was still loose.

If you lose connection of the neutral lug, are there any safety hazards likely such as the GEC becoming live?

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[inspector57]

If you loose the neutral reference, the voltage on 120 volt circuits can fluctuate as a function of the loads.

So yes it is a concern since you can blow bulbs and electronics.

This is a common source of bulbs dimming or growing brighter when various other loads are switched on and off.

Was this the service equipment where the neutral and ground are bonded or is the neutral "floating"?

[John Dirks Jr]

If you loose the neutral reference, the voltage on 120 volt circuits can fluctuate as a function of the loads.

So yes it is a concern since you can blow bulbs and electronics.

This is a common source of bulbs dimming or growing brighter when various other loads are switched on and off.

Was this the service equipment where the neutral and ground are bonded or is the neutral "floating"?

Thanks Jim. But are there any concerns of shock hazards to occupants?

[John Dirks Jr]

Doubled branch circuit neutrals on the left side as well.

[Jim Port]

Looking at the setscrew looks like it was tightened. It looks more like a short happened at the lug.

[John Dirks Jr]

Looking at the setscrew looks like it was tightened. It looks more like a short happened at the lug.

I saw the set screw like that too. But when I pushed on the neutral it easily moved around in the lug. Maybe it's cut too short. Most of the blackened is from the anti seize compound boiling off from the heat of resistance.

[inspector57]

If you loose the neutral reference, the voltage on 120 volt circuits can fluctuate as a function of the loads.

So yes it is a concern since you can blow bulbs and electronics.

This is a common source of bulbs dimming or growing brighter when various other loads are switched on and off.

Was this the service equipment where the neutral and ground are bonded or is the neutral "floating"?

Thanks Jim. But are there any concerns of shock hazards to occupants?

No as long as the ground is connected to the panel, you have ground reference but this is not to say there is no electrical hazard due to the extremely high voltage possible on different "hot" legs.

[Trent Tarter]

Here's the worst one I have found. Panel had to be replaced.

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[Jim Katen]

If you lose connection of the neutral lug, are there any safety hazards likely such as the GEC becoming live?

If you lose the normal low-resistance path at the neutral, then more current is going to flow on the relatively high-resistance path at the GEC. That current will be looking for any opportunity to return to the transformer and, if the resistance is right, it might flow through a person who's touching anything connected to an equipment grounding conductor.

[Marc]

It's absolutely a hazard to the occupants. Instead of getting an even 120/120 divide on the incoming 240 volts, you might get 200 on one side and 40 on the other. You can get anything from zero to 240 volts on any receptacle or single pole outlet in the house.

It can burn appliances, bulbs, TV's, computers, anything that plugs into an outlet.

And of course, an electrical fire can result very easily.

Marc