Panel voltage problems

[fireryan]

I got a panel where I am getting some wierd readings. With the panel off the voltage reads 120 l1-n and 240 l1-l2. When I turn the panel on I get 240 on l1-n which tells me I got a neutral problem. The strange thing is that when I pull certain fuses the problem goes away and if put some other fuses back in the problem returns. It's a bunch of different circuits that is causing the problem

 

[jumper]

I once had a bad neutral with one MWBC that caused me to see similar results in the panel.

Fixed it and everything was fine.

Never did totally understand why the one circuit affected a lot of the others. A bad main neutral, yes- but this only one MWBC.

 

[GoldDigger]

I got a panel where I am getting some wierd readings. With the panel off the voltage reads 120 l1-n and 240 l1-l2. When I turn the panel on I get 240 on l1-n which tells me I got a neutral problem. The strange thing is that when I pull certain fuses the problem goes away and if put some other fuses back in the problem returns. It's a bunch of different circuits that is causing the problem

If there are no loads (however small) connected between L2 and N, you will not see a solid 240V between L1 and N. I think that can explain why you see the voltage changing as you remove and replace branch fuses.
Stop trying to diagnose the problem this way, since you are likely to damage expensive equipment connected to the output of the panel.
Open the main connection and then carefully try to find out where the neutral conductor is open. Most likely, though the problem is in the service conductors, which will remain energized, or up the POCO power pole. If you see this open neutral as far back as the meter base, you will need to contact the power company to take the next step.

 

[fireryan]

There is nothing in the house to damage as everything is unplugged and not in use. Think I got it traced back to possibly the poco neutral connection. It just wierd since there is no loads on any of the circuits

 

[GoldDigger]

There is nothing in the house to damage as everything is unplugged and not in use. Think I got it traced back to possibly the poco neutral connection. It just wierd since there is no loads on any of the circuits

Either there are some hidden loads (think doorbell transformers, for example) or the whole effect you are seeing is being measured with a high impedance voltmeter and what you are seeing is the result of differing capacitances to ground on the various circuit runs.