Is there an issue wiring a traditionally single-pole receptacle as a double-pole? (i.e. Instead of L-N-G, it would be L1-G-L2)

Hmmm. When I started typing this I could not find an IEC-320-C13 to NEMA 6-20P power cable to save my life. I have... so the question is more of a curiosity at this point. But such a cable is difficult to resell as opposed to one with a NEMA 5-15P termination....

Would such a wiring decrease the ampacity of the outlet? This is fine to me. Just means I need a bunch more. Equipment will be pulling max of 6A at 240v.

Thanks! If you're further curious about this read on but that pretty much sums up my question.

I'm searching for cost effective means of wiring my equipment. I've purchased five Tripp Lite PDU1230 for a cost of ~$800. This can wire up probably all the equipment I have. But I have space for about 5x the equipment. I can wire up everything for less than $1600 (subpanels, wire, connectors, outlets, etc.) versus $4000 in PDUs. But it's contingent on wiring a 5-15 receptacle as L1-G-L2 vs. L-N-G.

Using NEMA 6-20R/P will be significantly more expensive (~$2,000) than the 5-15 but cheaper than the PDUs.

Clarifications / Update

This is for 240v devices only; in an area with only 240v devices (racks of them); accessed, operated, and maintained by myself only.

Other precautions such labeling area as "240v only"; placing plug covers over the unused receptacle; limiting one device per outlet, etc. can all be done. (Again, I'm the only person with access though.)

I'm not looking to increase ampacity as someone commented below. I'm assuming the doubling in voltage, if anything would halve the ampacity. In this case 6A is 80% of the 7.5A capacity and therefore save to use.

This question is, as I mentioned above, "more of a curiosity at this point."


2 Answers 2


Change sockets too

When you change the circuit voltage, simply change the socket also. Your normal common Mr. Horrorface socket is called a NEMA 5-15. You will simply be replacing it with Mr. Nope, aka a NEMA 6-15. They're common as dirt, every hardware store has them.

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As far as your power cords, if you can't find a C13 to NEMA 6-15, you're just not trying very hard. I found it ridiculously easy, try it yourself. Your 6A device (<= 1440 VA) should use a NEMA 6-15.

The NEMA 6 family has the same rules as the NEMA 5 family: the 6-15 plug will also plug into a 6-20 receptacle, and you can use 6-15 receptacles on a 20A circuit as long as there are at least 2 sockets on the circuit.

Only use 6-20 plugs on machines which actually need more than a 6-15 can supply, i.e. 3600-4800 VA non-continuous or 2880-3840 VA continuous. Such large loads are not a good match to the IEC C13 connectors, because they were never intended for near-20A current. Such large loads would use a burly connector like NEMA L6-20.

So go buy the right cord - they are $7 - or just lop the plug off a C13/5-15 cord, and attach a 6-15 plug. Don't know what your hardware store charges for those, probably $4. As far as resellability, lots of bitcoin miners want that stuff.

If you are sweating bullets over a $7 power cord, then your cheapness is an accident waiting to happen. If you do not want to spend money on plugs and sockets, them simply lop the plugs off, buy $1 strain reliefs and hardwire them into 4x4 junction boxes.

Also, don't rely on the Internet for pricing electrical gear. No wonder you're getting sticker shock. Everything on the Internet is stupid expensive because they are generally low cost parts that are expensive to ship. Talk to your 3 nearest electrical supply houses and tell them you're buying a lot of gear and not happy with the prices at Home Depot. Or the advice.

  • Thanks. The ones I found were $14. I did a few Amazon searches. Equipment is 1440 VA continuous. $9 delta from $5 5-15P power cord for 200 devices is $1800. Thanks for junction box route, might be final solution!!! Commented Nov 12, 2018 at 5:13
  • 1
    Yeah, the Internet is your problem there. You really need to find your friendly neighborhood electrical supply house and befriend them. You just can't price electrical gear online, it's priced over the moon because only fools, foreigners and the very desperate buy electrical gear that way. Commented Nov 12, 2018 at 5:27

Just NO

NEMA 5-15 is, by definition, designed for 120 V operation.

  • If you put 240 V on it, you are not using it as designed, therefore violating code.

  • Plus risking serious hazards because the parts may not be over-engineered enough to operate safely at 240 V.

  • Plus risking serious hazards if anyone ever forgot that this particular ordinary looking outlet was actually 240 V - e.g., what if you are doing some troubleshooting and need to plug in some other piece of equipment and unplug one of your servers to plug in a piece of expensive test equipment that gets destroyed - or a piece of cheap test equipment that starts a fire.

FYI (but not relevant, because you just can't do this!), such a change would not increase the ampacity (that would still be 15A) but would double the power because power = voltage * current.

But just don't do it. Not legal. Not safe.

  • 2
    To add to this, the NEMA configurations are specifically made to AVOID having someone do exactly this. The socket itself doesn't really "care", but if you wire a 5-15 socket as 240V, and someone plugs in a 120V device, it can start a fire.
    – JRaef
    Commented Nov 12, 2018 at 2:15
  • 1
    The receptacle will most likely survive the exposure to 240V; however, what's plugged into it very well may not! Commented Nov 12, 2018 at 2:40

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