Electrical Wiring in the Home/electrical to the workshop


hello Greg  i just pulled new power to my workshop from the house main panel.  it's about 20' breaker to breaker.  I installed a 24 slot 100 amp panel only using 6 breakers. #1 for each side of the light in the shop #NORTH&SOUTH# 1 for the north wall outlets 1 for the south wall outlets 1 for the welder 1 for the compressor Here is the question: why is it when i turn on the lights on if the fan is plugged into an outlet it speeds up?  When i turn them off it slows down?   I have also noticed the compressor #110v#motor runs slower.

It sounds like you are experiencing a voltage drop.

The things that can cause a voltage drop are the following:

1. The wire size from the main is not large enough to handle the loads properly.

2. You have loose wire(s).

3. Your breaker supplying the panel is worn out.

4. You have your circuits in series instead of parallel.

The panel in the workshop is a sub panel so you have to make sure your neutral and ground are not bonded in the sub panel.

Make sure you have a double pole 100 amp breaker feeding your new sub panel and that the wire size is large enough to handle the 100 amp sub panel. That means your neutral has to be large enough also.

Check all your connections. If you used aluminum make sure to put antiox on the connections after you tighten them.

If you could send me a photo of both your sub panel and main panel with the breaker covers off that would be great.
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Electrical Wiring in the Home

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Greg Hughes


Troubleshooting electrical including appliances and HVAC.


34 years of experience.

Both college and tech schools in this field.

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