And also the fact that I may not need the sub connected to ground rod.Like I said I would not recommend it. It will not improve the sound of your audio system. In fact it may degrade the sound. Lightning loves an auxiliary grounding electrode though. Lightning strike travels through the earth, enters the aux ground rod travels up through the ground wire to the equipment ground bar on its way to the main electrical and on its’ merry way back to earth. Suppose it stops and looks around inside the sub panel on its’ way back to earth?
The earth does not possess some magical mystical power that sucks nasties from audio equipment.
Adding an additional ground rod to the main electrical service Grounding Electrode System may lower the grounding electrode to soil resistance. IEEE recommends 5 ohms or less.
FYI the main reason for connecting the electrical service to the earth is for lightning protection. You can have as many ground rods installed for the main electrical service as you like as long as they are all tied, connected together, and connect to one point at the electrical service equipment. No matter how many electrodes there are they are counted as one.
The distance between the two panels will be less than 15’.How big/size, ampere handle rating, will the two pole breaker in the main electrical panel be that will feed the sub panel? Feeder wire size?
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