3 Prong Power Cord Install???

[Kregg]

I know I'm late to the party, nevertheless, here's a straightforward illustration: http://www.ceriatone.com/images/layoutP ... iatone.jpg

Happy New Year All!

[Phil_S]

... looking at the pics in my last post, which wire is the primary?

"Primary" refers to the primary winding on the power transformer. It is where the a/c input is applied from the "wall".

There is a white or gray (can't really tell from the pic) wire from the fuse to the transformer. That is one leg of the primary. The other leg of the primary is a black wire.

You have the white wire (neutral) from the a/c wall supply going to the fuse. In this configuration, it is possible for the fuse to fail, but you could still have active a/c input. There are two reasons. One is that the green wall supply ground is a redundant neutral and will allow conduction from the black to the green. The other is that your hand on the chassis will create the ground and the rest of your body will shunt the a/c supply off the chassis. This sort of experience can range from an exiting tingle to a painful shock to a burn to death.

Swap the black and white wall supply wires -- black a/c wall supply to the fuse, white a/c wall supply to the black transformer wire directly. When the fuse blows, the hot side of the a/c wall supply will be dead at the fuse. This is much safer.

[Structo]

Wow!

Three pages on a cord change!

[lakehaus]

Wow!

Three pages on a cord change!

Yeah, amazing ain't it? I'm new to this stuff, and a lot of the terms and diagrams provided I simply don't understand.

I do appreciate all the help, and I think I have it now (finally). You guys did a fine job educating this novice!!! Thanks for the support.

I'll have the chassis with new cord ready for the cab when it comes back from being re-tolex'd.

[selloutrr]

I have to ask since this has gone this far. I Completely agree with removing the death cap but I see a problem with the answers so far.... Everything posted other then the diagram I posted ( which you are telling me is no longer to code ) bypasses the use of a ground switch. Most amplifier still come standard with a ground swtich so how would you wire a grounded power cord to meet current code and incorporate a ground switch safely?

[Structo]

Not trying to be a smartass at all here but what amps still come with a ground switch?

I know that with a three prong cord you have to assume that the house wiring is the correct polarity so what purpose does a ground switch serve?

It seems like it would be even more dangerous to have one and have an end user not understand what it's for and have the hot wire on the wrong side.

[selloutrr]

It's all good, Off hand?... i'll look when I get home. I mostly deal with older amps that have value. I guess new amps might not be the correct choice of words. I can't think of any amp built in the last 5 years that I would have gone to a store and purchased. Oh wait.. Epi Jr. i did buy a couple of those. but they are so far from stock i'm not sure what you would call them Point goes to Structo! Let me rephrase... How would you safely incorporate a ground switch on an older amp ? clients hate holes and useless switches.

[Structo]

I wasn't calling you out, I was just curious as I hadn't seen any newer amps with them.

As far as the vacant hole, master volume?

[selloutrr]

Calling me out? I was just giving you props! it's all good!

at what time did they stop adding a ground switch?

I'm not huge on mods... they tends to kill the value of the amp and I can't bring myself to drill holes. I've found it's easier to convince the wife i need to buy another amplifier

[selloutrr]

let me run this thought by you.... for get a cap on the ground.. I'm with you! black to fuse white to power if not both to a power switch then primary's of transformer. Ground to chassis. how about ground to switch then to ground. that would make it the same as using a ground lift adaptor, right? then switch is used probably almost always left enguaged.. all good. then the rare moment the PA isn't on sound power float the ground and loose the hum of moving lights.