power upsurge

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New member
my question is this.i am remodeling a 1960 home with a zinsco 100 amp panel and when a piece of equipment (say a small air compressor)is going on one circuit and say a saw is going on another circuit it causes the compressor to speed up.has anyone ever come across an upsurge like this in a residencial home?

George Stolz

Staff member
Windsor, CO NEC: 2017
Service Manager
Yes, it's a sign of a resistive or open neutral. It would be a good idea to get an electrician to examine the system and make any necessary repairs, before the problem gets worse.


Senior Member
Hey George, I saw this once in an old masonry built apartment complex. Was a remodel job. Carpenter run saw and lights came on! Checked some receptacles with meter and had 165 volts. Checked side of panel can, had about 70 volts. Went to meter bank to find neutral was never even connected. Building had emt conduit. I guess conduit was the neutral??? How could tenants have lived in place for fourty years without this being located? Wouldn't you have damage to appliances etc.?? Thanks
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