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I never brought up how my grounding system is wired. The subject is not about that. All my enclosures are grounded to earth ground. It is understandable why grounding can be an asset for protection: We can't assume that everything is insulated/isolated in the same fashion, especially when considering vintage equipment. The main subject is that noise can travel through ground systems. Grounds can either help noise issues or agitate them. I wanted to bring up why these things can happen.
Hi Dan, I never had a problem with grounds. It's a completely hypothetical thread pertaining to possible problems and what can cause them.
Only problem is that the National Electrical Code is no longer standing behind balanced power in home applications from other threads I have read. Interesting as it was fine for awhile. Anyone else read about this? Just trying to see if it is correct.
647.3 General. Use of a separately derived 120-volt single-phase 3-wire system with 60 volts on each of two ungrounded conductors to a grounded neutral conductor shall be permitted for the purpose of reducing objectionable noise in sensitive electronic equipment locations provided that the following conditions apply. (1) The system is installed only in commercial or industrial occupancies. (2) The system's use is restricted to areas under close supervision by qualified personnel. (3) All of the requirements in 647.4 through 647.8 are met.
(D) Voltage Drop. The voltage drop on any branch circuit shall not exceed 1.5 percent. The combined voltage drop of feeder and branch-circuit conductors shall not exceed 2.5 percent. (1) Fixed Equipment. The voltage drop on branch circuits supplying equipment connected using wiring methods in Chapter 3 shall not exceed 1.5 percent. The combined voltage drop of feeder and branch-circuit conductors shall not exceed 2.5 percent. (2) Cord-Connected Equipment. The voltage drop on branch circuits supplying receptacle outlets shall not exceed 1 percent. For the purposes of making this calculation, the load connected to the receptacle outlet shall be considered to be 50 percent of the branch circuit rating. The combined voltage drop of feeder and branch-circuit conductors shall not exceed 2.0 percent.(FPN): The purpose of this provision is to limit voltage drop to 1.5 percent where portable cords may be used as a means of connecting equipment.