$vboptions[bbtitle]

OK to use 2-prong courtesy outlet on BFDR after I have a 3-prong AC cable installed?

chamberpop
April 13th, 2011, 03:06 PM
... cause the tech that installed the grounded 3-prong AC cable disconnected it and says it's not safe to use. I usually just plug my 2-prong pedalboard plug into the courtesy outlets of old Fenders.

Is there a safety hazard in doing that?

Thanks,
c-pop

bdgregory
April 13th, 2011, 04:05 PM
except for the fact it was disconnected by your tech, no reason you can't use it. It would be no different than if you replaced it with a proper 3 prong outlet, and only plugged a 2 prong cord into it.

rangercaster
April 13th, 2011, 04:18 PM
if he disconnected it, it shouldn't work at all ... if he changed the wiring and made it unsafe, that is irresponsible and dangerous ... he should either have made it safe or disabled it ...

chamberpop
April 13th, 2011, 04:24 PM
Yes, he disconnected it and it does not currently work.

He did not change anything otherwise.

How would one "make it safe". Isn't it already safe to plug a 2-prong cord into a 2-prong outlet no matter what?

thanks again, Folks.

Ricky D.
April 13th, 2011, 05:09 PM
Yes, he disconnected it and it does not currently work.

He did not change anything otherwise.

How would one "make it safe". Isn't it already safe to plug a 2-prong cord into a 2-prong outlet no matter what?thanks again, Folks.

Not trying to be a jerk about this, but why did you replace your 2-prong power cord with a 3-prong? :wink: You make that convenience outlet safe by changing it to a 3-prong.

Old 2-prong cords and outlets aren't polarized. One side hot, one side ground. The original BFDR cord could be plugged in either way, with a 50-50 chance of having voltage on the chassis (therefore your guitar strings, too). Anybody who gigged in the 60's remembers getting shocked by other players, microphones, etc. Your unpolarized convenience outlet presents the same grounding risk.

Singin' Dave
April 13th, 2011, 05:31 PM
So if he reconnected it, its safe to use for his application?

Bolide
April 13th, 2011, 05:47 PM
So if he reconnected it, its safe to use for his application?

It would need to be replaced with a polarized outlet, with one slot wider than the other, to be usable. I think you should just leave the dead outlet dead.

Just consider courtesy outlets to be a rather cheezie and potentially hazardous gimmick from an earlier time, and use a proper outlet box, preferably one with GFCI* built in.

*[Ground Fault Circuit Interupter, device which removes voltage if hot current is greater than return current at a level below that which is lethal, and only a fraction of the current needed to blow a fuse or trip a circuit breaker.]

Ringo
April 13th, 2011, 07:11 PM
Somewhere you can get a 3 prong outlet that will fit exactly to replace the vintage 2 prong outlet on the amp, I've seen some of the guys that post on the Weber amps and more board do that.

If I was going to use the outlet that is what I'd do.
I have a BF DR that I had the ac cable changed to a modern 3 prong cable, to be honest I had forgotten that it even has the outlet on the back, I'll have to ask my amp tech if he disabled it.

chamberpop
April 13th, 2011, 08:29 PM
Yes, it is in fact polarized (one slot wider than the other). I have never heard of anyone replacing a courtesy outlet, but I don't doubt it is done. Guess I just never read anything from any guitar forums about it. I just want to plug in a 2-prong plug. Is it safe?

Thanks.

dsutton24
April 13th, 2011, 08:57 PM
Your unpolarized convenience outlet presents the same grounding risk.

Yes, entirely true.

The safest thing would be to replace the courtesy outlet with a three prong outlet. But, there's no electrocution risk using the original two prong outlet with devices powered by a wall wart, as there's no reference carried through the power supply. Also, anything that is double insulated would also be safe.

I'm sure things exist that would be a problem (like older stuff), but in general if a device has substantial metal exposed that could be energized, that device will be supplied with a three conductor cord. Two prong polarized cords are used on things that aren't likely to be a problem.

Bad things can always happen, but the risk of using the courtesy outlet to power a pedal board is probably minimal. If you have to open the thing up to rewire the outlet, why not just replace the outlet while you're there? That way you're safe, and anyone else down the road will also be okay.

supersam
April 13th, 2011, 11:01 PM
Holy crap! Is that what that weird outlet on the back of my '69 Princeton is? I feel ashamed to have never figured it out. I've always wondered what it is, but for some reason I've never actually looked into it. So it's just a regular outlet to plug a two prong cord into? :oops:

Ed Storer
April 14th, 2011, 12:59 PM
If the item you're plugging in has a non-polarized 2-prong plug, then it's OK to use the convenience outlet on the back of your vintage amp.

I use mine ot power my pedal board.

The plug is non-polarized if you can plug into a 3-wire outlet and then flip it over and plug it in the other way.