The cable you installed is not like regular Romex though. Romex, NM-B sheathed cable, 14 gauge, 12 gauge, and 10 gauge, the safety EGC (Equipment Grounding Conductor) is the same size as the hot and neutral conductors.
In the event of a Hot to EGC ground fault the EGC must be capable of handling the maximum available fault current back to the source, the Utility Power Transformer.
Many layman think because the branch circuit wiring circuit breaker is 20 amps, the fault current will be limited by the 20 amp breaker. That is false... 100s to over a 1000 amps could travel in the faulted circuit instantaneously before the 20amp breaker, hopefully trips open. The bigger the size of the branch circuit wiring, the greater the available fault current in the circuit.
So I have to assume if the electrician was licensed, he used the red #10 AWG conductor for the EGC. Not the little small gauge shield drain ground wire.If the small shield ground was used. In the event of a Hot to EGC fault, the high fault current would more than likely melt the small gauge wire like a fuse. My guess it would burn, blow, itself free at the duplex outlet EGC ground contact lug screw. At any rate it will break, open, the ground fault circuit.
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Do you still have the electricians phone number? Could you give him a call? Find out what he actually did for the EGC wiring? Did he use the red #10 conductor for the EGC?
Do you know someone that is comfortable removing a panel cover and putting it back on?
My electrician being smarter than me ran the 4 lines off a 50 amp box that a Hot Tub was on but not being used because I moved the Hot Tub. I had calculated the distance from a sub-panel to the target wall behind the gear when I purchased the Hidden Treasure but because the 50 amp box is on the target wall he only used a fraction of the wire I purchased.
the 50 amp box is on the target wall he only used a fraction of the wire I purchased.
50 amp box?
A 50 amp 120/240 volt sub panel? The electrician installed four 20 amp single pole breakers in the sub panel for the 4 dedicated audio branch circuits?
IF there is a sub panel with four 20 amp breakers for the 4 dedicated circuits, that’s good...
There will be a 2 pole 240 volt 50 amp, (???), breaker in a sub panel or in the main electrical panel you can turn off and kill the electrical power to the sub panel that feeds your audio equipment. Verify 100% the panel is dead. None of the audio equipment outlets should have power to them... Verify 100%...
When you are 100% the power is off, then have your friend remove the panel cover. Have him look for the 4 red insulated 10AWG copper wires/conductors. One from each of the 4 cables.
Hopefully they connect to a separate ground bar that is bolted directly to the metal enclosure of the panel. There should be an EGC ground conductor that is part of the feeder wiring that feeds the sub panel.
All white neutral conductors are connected to an isolated, insulated, neutral bar that is insulated from the panel metal enclosure.
Feeder. Four conductors total. 2 Hot 240V conductors. One white neutral conductor and one EGC conductor. (Might be bare or insulated green wire.) (Feeder conductors? Might be copper, or aluminum).
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