What receptacle for 240V 20A in the States?


Just trying to get a bit more juice to my amp. It can be converted to run 120V or 240V (also with a quick change of the fuses).

However, I'm having some trouble finding a good receptacle. Any thoughts?

Thanks in advance!
Mike
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Your dryer probably runs off of 240. I guess you could get one of those big ol dryer cords and receptacles at Home Depot.
http://www.passandseymour.com/pdf/U029.pdf
will show you HD 240v devices

The power cord you have can be used for 240v because each conductor will be carrying half of what the hot conductor did when you were using the cord for 115v. Change the plug to the appropriate 240v and you're done.
You don't need a dryer cord. Your local hardware store has plugs for 220 volts, used for some large window air conditioners and shop tools. The plug looks just like a 3-prong 110 volt plug except the power prongs are turned 90 degrees.
Wagzel:

Your link leads to some great quality Pass and Seymore outlets but only one model (the 6-20 R) is designed to prevent it being used with a common 120 Volt household plug.

Murphy's law: IF someone can plug into an outlet..... they will.

Sure, the Hoover will vacuum better than ever for a couple of seconds, but the smoke and fire is not worth it.

Eldartford's suggestion is better.

The plug he's referring to cannot be mistaken for a 120 Volt nor will the 120 volt plugs fit the slot.
I'm assuming that you're in US/Canada, in which case there would be two hots at 120V each. These are out of phase and are cumulative to 240V, but they can NOT be combined together without a load. That would be a short.

It can be cheated by putting the two hots on a three-prong outlet, abandonning the neutral, and using the ground as normal. This would be 120+/120- or balanced 240V (or close to balanced). Electricians might not be willing to do "bend" the code and your insurance could be void if there were a problem. I usually suggest using GFCI protection for DIY balanced AC.

Europe has 240+/0- unbalanced AC. Technically 220V, but that's splitting hairs.
Just looking through the Hubbell catalog for Nema6-20r hospital grade duplex recepticals and brown is HBL8400 Ivory is HBL84001.These are rated at 20 amps 250 volt.The matching plugs areHBL8576E in white ergo grip.HBL8464V which is the valise style body in white.The 20 amp rated recepticals and plugs differ from the15 amp versions by having one vertical and 1 horizontal blade.Nema 5-20p or5-15p rated 125 volt style plugs can not be inserted in this style of receptical.
Not to through a fly in the ointment. But it is possible you may effect the sonics of the Amp. For better, or worse??

From the mains of the U.S. 240V you will essentially be feeding the Amp from a balanced power system. Also the voltage may be closer to 250V + . You may want to have that checked first. Also check what the maximum input AC voltage rating is for the Amp.

As for the NEMA 6-20R receptacle that would be a good choice. If you already have an extra 120V dedicated circuit by your audio system all you will need is a 2 pole 20 amp breaker installed at the electrical panel and the two insulated conductors of the dedicated branch circuit terminated on the 2pole breaker.
Guys, thanks for all the excellent responses!

I now have some receptacles and plugs. I bought 2 different types because I was not sure if I needed a 3 or 4 wire (Hubbell HBL2320 and HBL2410) while at the store.

I should have mentioned that the amp (originally from Europe) 220V but uses 1 hot, 1 neutral, 1 ground, like 120V in USA/Canada. I noticed that the new HBL 2320 receptacle uses 2 hots and 1 ground...Can I use this?

The HBL 2410 has 4 wires...I believe this is wrong for the application.

Jea48 - I actaully have 2 unused dedicated 120V lines, I wanted to connect both hots to make 240V. I am sure you are right about my voltage, it will be 250V, since I get about 125 on a single line. I was hoping to connect the 2 hots, a neutral and ground, then emulate what is happening in Europe.

Ngjockey - I don't know why this would be out of phase when the breakers are on the same buss bar? I am not trying to tell you that you are wrong...just trying to learn. Also you mention to cheat and put 2 hots on a 3 prong outlet...but I think that is how it looks on my oven for example.

Thanks again guys!
Mike
Angus80808, You will need to reconfigure one of the existing 120V dedicated branch circuits to a 250V dedicated branch circuit. At the electrical panel the 250V branch circuit must be connected to a 2 pole breaker. If the wire is #12 awg and the receptacle is a 20 amp then the breaker must be a 2 pole 20 amp breaker.

As in regards to phasing the power that feeds your home is fed from a split phase secondary winding of the power company's utility transformer. Single phase, only one phase. Two hot ungrounded conductors with a center tapped grounded conductor, the neutral.
Jea48 - Yes, as you mentioned, I will connect to a 2 pole breaker (2x 120V). The wire is #10 awg and will use with a 20 amp circuit...(or maybe 30A??) This makes sense to me.

I guess I'm worried that there is no neutral wire going to the amp, should I be?

Thanks!
Mike
NGjockey - Ha ha! Yes, I work with several EE's and technicians...I will invite one over to help, and to check it. Thanks for your concern!

03-03-07: Angus80808
Yes, as you mentioned, I will connect to a 2 pole breaker (2x 120V). The wire is #10 awg and will use with a 20 amp circuit...(or maybe 30A??) This makes sense to me.
Do not think of it as 2x 120V. It is single phase 240V. And no you will not need the neutral conductor. Just the two hot 240V conductors and the equipment grounding conductor.

As for the wire size being #10 awg, because of the 20 amp receptacle you are using the branch circuit over current device, (the 2 pole breaker in this case), must be 20 amp. Not 15, not 30, it must be a 2 pole 20.....

And as Ngjockey said in his post have an electrician do the job. 240V will kill you just as dead as 120V
Jim
As for the wire size being #10 awg, because of the 20 amp receptacle you are using the branch circuit over current device, (the 2 pole breaker in this case), must be 20 amp. Not 15, not 30, it must be a 2 pole 20.....

I would exchange the receptacle and plug for 30A if I go that route.

Thanks again for your comments, I just wanted to understand what was going on.

Mike
I would exchange the receptacle and plug for 30A if I go that route.
Mike I would not recommend doing that. You will be fine with a 20 amp branch circuit. 240V X 20 amps = 4800 VA...
Jim

Jim, I'll take your advice and stay with the 20A.

The amp has the same transformer size as a Levinson #33 (10 kVa total), and I read that people were using 240V x 30 A or larger with those. I thought it made sense to do the same.

Thanks,
Mike