Not getting shocked

Discussion in 'Amps and Cabs [BG]' started by Sascrotch, Nov 28, 2001.

  1. Sascrotch


    Feb 18, 2001
    Costa Mesa, CA
    Ok, I'm relitivley unaware of the "science" behind musical equipment and I always wondered why people get shocked while playing. I know that its about not being grounded or something, but I don't fully understand. How does this happen? How can I prevent this with my own bass equipment?
  2. The #1 thing you should do at EACH and EVERY gig is check the power integrity. Go down to your local Radio Shack and buy a $6 power line checker. Always plug it into every outlet your are going to use... including the PA outlet. Shocks happen when one outlet is correct for the bass amp, and another amp for the PA is miswired. I have already found two instances of this with my checker.

    Do not plug in and do not play from outlets that are incorrectly wired. Believe the tool, and not the half-baked statements of the venue owner. It's your life you are betting with.
  3. BigBohn


    Sep 29, 2001
    WPB, Florida
    hey bgavin, do you have any links that get in-depth with the procedures of using a power line checker correctly? that would be great if you did. I have a question for you, you know those Furman PM-8 has a voltmeter and a ammeter, which displays the Voltage 0-140 and 0-20 amps, respectively. Is this a necessary thing that I should have over having one Furman with built-in lights? Thanks:)
  4. geshel


    Oct 2, 2001
    Oh boy, there was a big blowup on TBL about this a year ago or so. Despite the flames (I think I was guilty of this a bit too), I was enlightened about this matter a little.

    From my POV:

    1. Equipment should always be well grounded - meaning grounded plugs where the ground on the outlet is actually grounded :) If equipment has a metal case (amps, mics, etc almost all do) it should be firmly connected to ground. THis way, if a hot wire inside comes in contact with the case, it will short and blow the fuse before you are in danger of touching it.

    2. You, personally, want to be as *un*grounded as possible. Being personally grounded is *only* something desirable if you're having problems with static electricity - ie you are working on sensitive electronics. When you are grounded (ie through your feet if you're standing on wet ground, or the one hand on your strings if they are grounded through the bridge ground*), you become a convenient path for any hot improperly wired equipment (ie mics), and stand a better chance of being turned into a tasty morsel.

    * here is where the confusion lies. For whatever reasons (I know some but they aren't worth it), some basses and guitars have the bridge connected to the ground on the cable. This ground is typically connected to the case ground on your amp. For the reasons stated above, bad idea. Touching a hot mic without being grounded (rubber-soled shoes on wood floor for instance) will tingle. If your other hand is grounded via the strings, it could be much worse.
  5. Electrical safety is one of my pet subjects. I've seen some real horrors I can tell you.

    This topic's become quite a big issue in the UK: employers and industry generally have been forced to clean up their electrical systems. And that has spilled over to many walks of life because everybody is frightened witless of being sued at the drop of a hat!!!

    Most people now engage in some sort of electrical safety inspection and test and keep records of what they've found and done.

    Following that I regularly inspect the band's gear and replace / change / alter as required. What's more, I keep a small book to record these matters, dated and signed, so that should a law suit be waved around if someone got fried, we can say and prove that we took all reasonable care to avoid such matters.

    Most non-electrical people can inspect plugs / cables / etc and if they suspect a problem get it to a qualified person. And keep a note of the details.

    And Bruce gives a great piece of advice. Buy an outlet checker and use it. It could save your life. Also, we run our whole set up via an RCD (breaker) which hopefully will protect us in the event..... Consider that, too.

    There's more to be said if anyone's interested but I'll not go on unless asked.