Alternative Ground for electric piano

McWhanTobin

Greetings,

I am an American musician living in France. Most of my gear is American, and my keyboards and amps require a step-down transformer. The transformers I have that are not dedicated to more energy intensive uses can receive a 3 pole plug (hot, neutral and ground, I believe) but do not have a ground on the male end, thus the ground dies in the transformer.

Can I safely use an insulated wire (say, a speaker wire) to attach the ground pole on the plug to another ground pole in a unit that is grounded? Is this okay if the units themselves are linked by a 1/4 inch sound cable?

Thanks for your help!

AllanJ

It is almost always OK to take a ground wire and run it from one piece of equipment to the next, with the far end connected to a known ground such as plumbing that is all metal out through the foundation. The ground wire does not need to be insulated.

You can plug each piece of equipment into a 3 prong to 2 prong adapter and connect your ground wire to each of the adapter grounding lugs, or you can connect the ground wire to the frame (chassis) of each piece of equipment by using a screw that penetrates the plastic case or cabinet or already attaches to the chassis.

Occasionally you get hum in the audio if two or more ground connections such as the shields of two audio cables go from one piece of equipment to another. But I think that a separately run ground wire of 14 gauge or heavier should reduce instead of increase any such hum.

There is some older audio equipment that has the chassis connected to neutral instead of ground. Ordinarily you should not screw into the cabinet so as to hit the chassis. When you use a transformer for 240-120 volt etc. conversion that is not an autotransformer and has no connection between primary and secondary, then grounding that piece of equipment is perfectly OK.

__________________
The average homeowner who lost his house in the Oklahoma tornadoes should move for good and not rebuild. Too much complexity watchdogging the contractor. Too much a chance to be defrauded.

J. V.

If the ground wire (EGC) does not originate in the service panel and run within a single cable or conduit, it is a code violation in the US. While I do agree your idea is better than no ground at all, it is still a violation.

Example: If someone had 2 prong receptacles in their house, meaning no ground wire, could you run a separate ground from each receptacle back to the panel and then install 3 prong (grounding) receptacles in place of the ungrounded type? No, you could not. You would have to run new cables with the ground included.

spark plug

Alan J (Poster #2) I know for a fact that in some European countries (Germany, I believe) the National Certifying agency, which is the equivalent of the NFPA permitted electrical appliances to be grounded to the Neutral. And in those countries that this practice was not permitted, the Customs agents at the airport ended up being the Code enforcers. (No matter what)Don't drink and drive, Ever!!!