BillFitzmaurice.info

Went over to a friends old bar to help him hook up a sound system.

I got shocked by the board when unplugging a trs out that goes to an amp on stage. The exposed portion (sleve) as well as the screws on the face of the board are what appear to be "hot". Everything is hooked up properly and the outlets do have grounds (can't say they are wired correctly or not).

Any ideas and or ways to troubleshoot this, make sure it is safe, and correct the problem?

Thanks,

guitarkeys.com wrote:Went over to a friends old bar to help him hook up a sound system.

I got shocked by the board when unplugging a trs out that goes to an amp on stage. The exposed portion (sleve) as well as the screws on the face of the board are what appear to be "hot". Everything is hooked up properly and the outlets do have grounds (can't say they are wired correctly or not).

Any ideas and or ways to troubleshoot this, make sure it is safe, and correct the problem?

Thanks,

Get a little tester plug. They will tell you if the AC is wired properly. Sounds like the hot is shorting with the ground.

guitarkeys.com wrote:Went over to a friends old bar to help him hook up a sound system.

I got shocked by the board when unplugging a trs out that goes to an amp on stage. The exposed portion (sleve) as well as the screws on the face of the board are what appear to be "hot". Everything is hooked up properly and the outlets do have grounds (can't say they are wired correctly or not).

Any ideas and or ways to troubleshoot this, make sure it is safe, and correct the problem?

Thanks,

I have seen this with the power strips with EMI filters and a circuit that is missing the ground. My house was wired with all 2 wire wire and before we purchased they put grounded plugs in every outlet. I did not check to see that they were grounded, figured they were. The tester for this is simple (http://www.amazon.com/GE-50542-Receptac ... =ac+tester). The effect of an ungrounded EMI filter is to put about 85 volts AC into the ground circuit through the capacitors and the varistors in that part of the circuit. If there is no ground it will make the chassis of many amps 85 volts. It can and does pop input stages in home theater equipment as well as computer sound cards etc.

Jerry

Get a tester and check the ground......

JerryAllen wrote:

guitarkeys.com wrote:Went over to a friends old bar to help him hook up a sound system.

I got shocked by the board when unplugging a trs out that goes to an amp on stage. The exposed portion (sleve) as well as the screws on the face of the board are what appear to be "hot". Everything is hooked up properly and the outlets do have grounds (can't say they are wired correctly or not).

Any ideas and or ways to troubleshoot this, make sure it is safe, and correct the problem?

Thanks,

I have seen this with the power strips with EMI filters and a circuit that is missing the ground. My house was wired with all 2 wire wire and before we purchased they put grounded plugs in every outlet. I did not check to see that they were grounded, figured they were. The tester for this is simple (http://www.amazon.com/GE-50542-Receptac ... =ac+tester). The effect of an ungrounded EMI filter is to put about 85 volts AC into the ground circuit through the capacitors and the varistors in that part of the circuit. If there is no ground it will make the chassis of many amps 85 volts. It can and does pop input stages in home theater equipment as well as computer sound cards etc.

Jerry

Get a tester and check the ground......

+1 that's exactly the one I have.

You can get 'em at Home Depot too....

I used to have a behringer mixer that did this at about 70% of the locations it was plugged in at. Never had a problem with a different board on the same outlet. I finally tossed it.