Please explain the 1 volt part.Lets say that in the main panel the hots are 120 volts AC. The ground is at 0 volts. Because ground and neutral are bonded here, the neutral is also at 0 volts.Someone smarter than me can explain why subpanel neutrals and grounds aren't connected.
Lets say there is an ADU with a subpanel that incorrectly bonds neutral and ground. Lets say a space heater is on and drawing lots of power. Now, in this subpanel, ground and neutral are at 1 volt AC, and the hot is 119 volts AC.
There is a microwave oven on the kitchen counter. Because of the erroneous bonding, the microwave shell is at 1 volt AC. And the kitchen faucet may be connected via plumbing to the main house's ground. Lets say you drop an aluminum turkey pan and it bridges the faucet and the microwave. This means the pan bridges 1 volt AC. This may be enough to cause a spark. It might also divert enough current (as per lazydavid's post above) to vaporize part of the pan!
Statistics: Posted by bogles the mind — Fri Nov 22, 2024 6:01 am — Replies 56 — Views 3817