How to wire up a 240VAC receptacle

[Spork Schivago]

Hello,

I have a device that has an IEC 60309 3-prong 32 amp plug.   It expects a 3-prong receptacle that has neutral, ground, and line.   Because I live in the US, how could I safely wire up the correct receptacle that has neutral, ground, and line, while still providing 240VAC and not violating the NEC?

I have single phase 120-0-120 coming into the house to the panel.

Thanks.

[GerryBags]

You need a transformer. We use 120V on work sites in the UK, so there are plenty of 240V-120V "site" transformers knocking around. You could use one of those backwards, but not to the rated current draw as the secondary's likely to be lighter guage.

You really want something more like this: https://www.mtixtl.com/actoactransformer800wmaxdualchange220240v-110120vtf-220110-800-2.aspx

[Spork Schivago]

You need a transformer. We use 120V on work sites in the UK, so there are plenty of 240V-120V "site" transformers knocking around. You could use one of those backwards, but not to the rated current draw as the secondary's likely to be lighter guage.

You really want something more like this: https://www.mtixtl.com/actoactransformer800wmaxdualchange220240v-110120vtf-220110-800-2.aspx

Yes, I'd need some sort of step-up transformer.   That's where I'm getting stuck.   I need to go from 120VAC to 240VAC, but with the proper plug.   My device draws up to 7.3KVA but has a maximum rating of 10KVA in the tech documents.   I'm having trouble with figuring out what exact step-up transformer I'd need, what size breaker in the panel, etc.

I can send a pic of the actual plug, if it'd help.   It's blue and has three plugs.   I'd rather be able to plug this directly into the step-up transformer, rather than use some sort of adapter.

I am wondering if there's any way to tear the rack mount PDU apart and rewire it to accept the 120VAC L1, 120VAC L2, and neutral / ground?   Probably not, right?   Essentially, it's not as simple as just switching out the power cord, is it?   The only way is with a step-up transformer?

[Spork Schivago]

I'm looking at similar plugs on internationalconfig.com and see stuff that says 2P+E.   I read that means 2 pole plus earth, but does that mean 2 hots and one Earth?   If so, I wonder if my three prong plug expects two 120VACs and one Earth, instead of one 240VAC, earth, and ground?  The document on the PDU doesn't say much.   The model of the PDU is HPE P9S16A.

It was listed as Single-Phase international.   It was the only one that fit the requirements we had.   We couldn't get three phase ran here because of the price.  My plug has the 2P + Earth symbol written on it.

[Spork Schivago]

No, you don't need a transformer.  You just wire the device hot and neutral to the incoming split phase lines.
This is how every 240V device works in the US.

But what if the device isn't a US device?   Do you see what I'm saying?   I see the IEC 90603 IP44 32-Amps are a European connector.   In the US, we have 15 amp, 20-amp, 30-amp, etc breakers.   We generally don't have 16-amp or 32-amp breakers.   In Europe, they don't have two 120VAC lines like we do, I don't think, and this is the problem.   I believe the plug expects a ground, a neutral, and a 240VAC hot, not two 120VAC hots

[IanB]

I have a device that has an IEC 60309 3-prong 32 amp plug.   It expects a 3-prong receptacle that has neutral, ground, and line.   Because I live in the US, how could I safely wire up the correct receptacle that has neutral, ground, and line, while still providing 240VAC and not violating the NEC?

Either you can find the appropriate 240 V NEC socket that is rated for the current your device consumes and wire that up to your panel using the appropriate conductor thickness and current rating for the circuit breaker. Then you can construct a fly-lead with an NEC plug on one end and the correct IEC 60309 receptacle on the other. Or you can install the appropriate IEC 60309 receptacle directly in the wall at the end of your 240 V circuit.

Note that "normal" outlets are typically rated for 15-20 A maximum, so if your device consumes more than 18 A or so you will need a special dedicated circuit with the right current rating. Consult an electrician if you have any doubts.

[IanB]

But what if the device isn't a US device?   Do you see what I'm saying?   I see the IEC 90603 IP44 32-Amps are a European connector.   In the US, we have 15 amp, 20-amp, 30-amp, etc breakers.   We generally don't have 16-amp or 32-amp breakers.   In Europe, they don't have two 120VAC lines like we do, I don't think, and this is the problem.   I believe the plug expects a ground, a neutral, and a 240VAC hot, not two 120VAC hots

Although some parts of Europe have a line-neutral-ground arrangement, other parts of Europe may have a line-line-ground arrangement. So it's highly unlikely to make a difference to your device if you feed it the North American version of 240 V with two lines and no neutral.

[helius]

I believe the plug expects a ground, a neutral, and a 240VAC hot, not two 120VAC hots

As long as the device is properly designed and constructed, it makes no difference.

[Gregg]

A lot depends on how the device that you are powering is configured.  If you can find the manufacturer’s installation documents, it is a possibility that you can wire it to your 240V household panel with its own 30 amp two pole breaker.  If it is something like an inverter welder, this is a pretty good possibility. 
The IEC 60309 plugs are labeled L, N, and G for reference as they are used in many other countries where the neutral is closely referenced to ground and the labels are to keep connections standard.  Just make sure you get the ground correct if your equipment can use 120/240 volt power directly.  There is nothing wrong with IEC 60309 plugs and receptacles; but they are not cheap.  A set of L6-30 twist locks may be cheaper than buying the IEC 60309 receptacle.

[Spork Schivago]

So, just to be clear, so long as I purchase a 2P+E 32-amp receptacle, I can just wire the hots from a double pole 20-amp breaker, and run one of the hots to the neutral?    Or do I run one of the hots to the ground?    The receptacles I've been looking at for this have ground, neutral, line, where line is 240VAC.

Instead of hooking neutral to neutral, I'd hook neutral to 120VAC, then line to 120VAC, and ground to ground?   Using 12/2?

The device draws a good bit of current, but nothing insane.   7300KVA, or around 30 amp when running optimally (80% load).

[Spork Schivago]

A lot depends on how the device that you are powering is configured.  If you can find the manufacturer’s installation documents, it is a possibility that you can wire it to your 240V household panel with its own 30 amp two pole breaker.  If it is something like an inverter welder, this is a pretty good possibility. 
The IEC 60309 plugs are labeled L, N, and G for reference as they are used in many other countries where the neutral is closely referenced to ground and the labels are to keep connections standard.  Just make sure you get the ground correct if your equipment can use 120/240 volt power directly.  There is nothing wrong with IEC 60309 plugs and receptacles; but they are not cheap.  A set of L6-30 twist locks may be cheaper than buying the IEC 60309 receptacle.

I'd void warranty if I replaced the plug.   I'm going to purchase the receptacle from Europe.   Buddy of mine over there has them dirt cheap.

The pics I uploaded have the L1 and Earth symbol (G), but doesn't list N.   This equipment cannot run off 120VAC by itself.   It's not one of those 120V or 240V.   It requires 200VAC - 240VAC to operate.   It's just a Power Distribution Unit for a server rack.   A horizontal, metered one, made by Hewlett Packard Enterprise (or at least they outsourced someone to make it for them).

For my cheap BGA rework station, I used the NEMA L6-30 twist locks.   They're okay, feel kinda cheap, but eh.   It works and passed inspection.   I want to make sure this passes inspection before I fill out the paperwork for the permit and purchase the receptacle over in Europe, purchase the wire, run it, and also make sure it's definitely not gonna fry the PDU.

[IanB]

So, just to be clear, so long as I purchase a 2P+E 32-amp receptacle, I can just wire the hots from a double pole 20-amp breaker, and run one of the hots to the neutral?    Or do I run one of the hots to the ground?    The receptacles I've been looking at for this have ground, neutral, line, where line is 240VAC.

It will make a nice bang if you connect a hot wire to ground 

Instead of hooking neutral to neutral, I'd hook neutral to 120VAC, then line to 120VAC, and ground to ground?   Using 12/2?

The device draws a good bit of current, but nothing insane.   7300KVA, or around 30 amp when running optimally (80% load).

The best way to think about things is to forget that "neutral" wires exist. Just consider all power conductors to be hot, and keep them well away from ground.

Note that a 20 amp circuit is no good for a device that will draw 30 amps or more. You will probably want a 35 or 40 amp circuit for that (with appropriate wire thickness and breaker).

[Spork Schivago]

So, just to be clear, so long as I purchase a 2P+E 32-amp receptacle, I can just wire the hots from a double pole 20-amp breaker, and run one of the hots to the neutral?    Or do I run one of the hots to the ground?    The receptacles I've been looking at for this have ground, neutral, line, where line is 240VAC.

It will make a nice bang if you connect a hot wire to ground 

Instead of hooking neutral to neutral, I'd hook neutral to 120VAC, then line to 120VAC, and ground to ground?   Using 12/2?

The device draws a good bit of current, but nothing insane.   7300KVA, or around 30 amp when running optimally (80% load).

The best way to think about things is to forget that "neutral" wires exist. Just consider all power conductors to be hot, and keep them well away from ground.

Note that a 20 amp circuit is no good for a device that will draw 30 amps or more. You will probably want a 35 or 40 amp circuit for that (with appropriate wire thickness and breaker).

What I did, before I read your post, was take my DMM and read the continuity between the pin with the Earth symbol and the external earth symbol green screw and seen 0 ohm resistance and came to the same conclusion you did about the crispiness.

I measured between L/+ and the unlabeled one and got 0.391Mohm (mega ohm).   Then I measured between the unlabeled pin and Earth and got infinite.

I believe I will be good with a double pole 20-amp breaker, where each breaker is providing 120VAC at 20-amp.   Correct me if I'm wrong here, but two 20-amp breakers each providing 120VAC would be equal to one 240VAC breaker allowing up to 40-amp current draw, correct?   If I were using one breaker, then yes, I'd need a 35 or 40 amp breaker, but because I'm going to use a double-pole 20-amp breaker and run one of the hots to the L/+, and the other hot to the unlabeled pin, the neutral to the Earth symbol, I should be good to go, right?

What type of wire would I buy that wouldn't have the bare copper ground but three coated individual wires inside?   Would it be 12/2 without ground?   NM-B should be fine for basement installation, right?

[IanB]

I believe I will be good with a double pole 20-amp breaker, where each breaker is providing 120VAC at 20-amp.   Correct me if I'm wrong here, but two 20-amp breakers each providing 120VAC would be equal to one 240VAC breaker allowing up to 40-amp current draw, correct?

Not correct. 20 amps is 20 amps. If your load is 40 amps you need a breaker and circuit rated at more than 40 amps (using the appropriate safety margin according to the relevant section of code).

What type of wire would I buy that wouldn't have the bare copper ground but three coated individual wires inside?   Would it be 12/2 without ground?   NM-B should be fine for basement installation, right?

It's probably best you employ a commercial electrician. Once you start asking these sorts of questions it suggests you are out of your depth.

[radar_macgyver]

What type of wire would I buy that wouldn't have the bare copper ground but three coated individual wires inside?   Would it be 12/2 without ground?   NM-B should be fine for basement installation, right?

If it's to go from the wall plug to device, you shouldn't use NM, that's for in-wall use only. You can get either SOOW cable or type-W cable for this purpose. For in-wall use, if you want a cable type that has an insulated ground, consider type MC cable. Both SOOW and MC are available at home improvement stores. Type-W is usually only sold at electrical supply stores, or  you can buy online. My preferred vendor is https://www.wireandcableyourway.com/

Buy a pocket NEC guide for information on selecting wire gauge etc. Or, as IanB says, get a pro to install an outlet.

[Richard Crowley]

If your mystery device draws 30A, and given your apparent lack of expertise with mains wiring, then you should NOT be trying to rig up something DIY.  You need a proper, high-current branch circuit with the proper gauge wiring from the distribution point ("breaker panel") and a suitably-rated circuit breaker.  No amount of fooling around with typical 15 or 20 amp branch circuits is going to deliver what you need. The connector is the least of your issues.

[Spork Schivago]

Guys, listen, I tried the professional electricians.   They're all good until they see the pic of the plug, and then they say they can't do it.

That's why I'm here, to make sure I don't hurt myself.   If I could pay someone, I would.   But now I think is a good time for me to learn some stuff.    I thought each line would be able to provide up to a 20-amp draw, as in 20-amp draw from one hot, 20-amp draw from another, with the double-pole breakers.   You guys are saying that's not the case though?   Because the pins are separated from each other by the 0.391 mega ohm resistance or whatever it was, I am looking at those two lines not really as one.   I gave the model of the device in the first post.   It's an HPE P9S16A PDU.

I'm looking at how the receptacle is supposed to be wired up, and we're going against that, obviously.   The receptacle is supposed to have one neutral, one ground, one 240VAC hot.    The professional electrician who came in and installed the 200-amp panel had his work inspected, and it passed, and he used NM-B.   I thought that was wrong, after reading what NM-B was for, that's the reason I asked.   If I don't know something or if I doubt something, I'll ask, instead of just doing it.

I have no problems using a 40 amp double pole breaker, but I think the most important part is for me to understand why I need a 40-amp double pole breaker, so I learn.   Isn't it that each breaker can provide up to whatever they're rated?   So a 40-amp double pole breaker, each breaker can handle up to 40-amps of current?   I understand they're not meant to draw 40-amp continuously.

I wanted to go with what I've always called MX wire, but I think it's really called MC.   It's shielded with the metal around it.   But then I figured I'd run the NM-B and run it through conduit, like the electrician did.   I am glad to know that is not allowed.   Don't know how or why the inspector passed him on that.

[IanB]

You haven't been told you can't use NM-B to wire a fixed circuit from the breaker panel to a wall outlet. You can. That's why an electrician is able to do so and have the work pass inspection.

You keep getting hung up on "hot" and "neutral". But a circuit has two wires. You can think of them as "out" and "back". Whatever current flows "out" has to flow "back". 20 amps out, 20 amps back. The current in the two conductors is always equal and balanced. That's why you can't add up 20 and 20 to get 40.

You can work out for yourself why two 120 V, 20 A circuits do not add up to a 240 V, 40 A circuit. Think about it. 120 V x 20 A = 2400 W. Therefore 2 x 120 V x 20 A = 4800 W. But 240 V x 40 A = 9600 W. And 4800 W does not equal 9600 W. It doesn't add up.

If your load draws 30 amps then the "out" wire has to carry 30 amps and the "back" wire has to carry 30 amps, and each pole of the breaker has to carry 30 amps.

[Paul Moir]

The reason why the professional electricians can't accommodate the plug is that they're not allowed to wire in the European socket.  They must use sockets that are allowed for permanent installations in North America, which are pretty much NEMA sockets.  So have them wire in a dryer socket (30A) or a range socket (40A), then construct an adapter made with a dryer or range plug to your European socket. 
If you go out early on garbage day with a set of wire cutters, you can get the plug extra cheap. 

[Zero999]

Ian is right. It will make no difference. Here in the UK it's done the other way round: 110V equipment is routinely powered off 55V-0-55V split phase (55V with respect to neutral) or two phases of a 110V three phase supply (63.5V with respect to neutral). It's perfectly safe: it works without killing or shocking anyone!

[Spork Schivago]

You haven't been told you can't use NM-B to wire a fixed circuit from the breaker panel to a wall outlet. You can. That's why an electrician is able to do so and have the work pass inspection.

You keep getting hung up on "hot" and "neutral". But a circuit has two wires. You can think of them as "out" and "back". Whatever current flows "out" has to flow "back". 20 amps out, 20 amps back. The current in the two conductors is always equal and balanced. That's why you can't add up 20 and 20 to get 40.

You can work out for yourself why two 120 V, 20 A circuits do not add up to a 240 V, 40 A circuit. Think about it. 120 V x 20 A = 2400 W. Therefore 2 x 120 V x 20 A = 4800 W. But 240 V x 40 A = 9600 W. And 4800 W does not equal 9600 W. It doesn't add up.

If your load draws 30 amps then the "out" wire has to carry 30 amps and the "back" wire has to carry 30 amps, and each pole of the breaker has to carry 30 amps.

Thank you for explaining that.   I want to apologize for my response last night.   There's something really wrong with me and on Friday, the doctor said it was time to go to the ER.   But I was waiting until Mothers Day was over with.   I haven't gotten much sleep.   I'm real worried now.   I weighed around 207 lbs maybe 6 months ago and now I'm down in the 150 lbs, but nothing has changed.   I just keep dropping it.   At first, I was happy, but now, it's got us all concerned.   I'm going to be going to the ER later today and might not be back for a bit.

I purchased a 40-amp double pole breaker.

So, is there any danger with going for a larger breaker than what is actually needed?   I know I can run 14 gauge wire on a 20-amp breaker.   I know I can't run 12 gauge wire on a 15-amp breaker.   With this PDU and it's dedicated circuit, hypothetically, if I went for a 100-amp breaker, would that be dangerous?   Essentially, would it only trip after it draws more than 100-amp or would it trip as soon as it noticed some sort of short or something?    I'm not talking about GFCI breakers or arc-fault breakers.   Just the normal D-Square Home-Line ones.

For the NM-B, I thought radar_macgyver said it's for in-wall use only.   My receptacle is rated for the 32-amp, the proper mate to this plug.   When it says 32-amp, being a European plug, I believe that's 40-amp derated to 80%.   I believe that's how they categorize their breakers, at the derated current.

I'll be using 8-gauge wire, but I need clarification on the NM-B.   I see NM-B (non-metallic sheathed cable) may be used for both exposed and concealed work in normally dry locations at temperatures not to exceed 90°C (with ampacity limited to that for 60°C conductors) as specified in the National Electrical Code.  NM-B cable is primarily used in residential wiring as branch circuits for outlets, switches, and other loads.  NM-B cable may be run in air voids of masonry block or tile walls where such walls are not subject to excessive moisture or dampness.  Voltage rating for NM-B cable is 600 volts.

For the receptacle, they show no bare copper wires being hooked up, so I was thinking of going for something like 8/3 without ground, but then using the neutral for ground.   Would that be best or would it be better to go for 8/2 with ground, and just hook the copper ground to the ground pin?   I'm bonding the PDU to the rack, and the rack to the bonding cable that bonds the ethernet, coax, gas-lines, waterlines, etc together.   I know I have to mark any non-black wires with red tape or something to show the next person it's hot.

The reason I feel I need to understand this is because some kid (from the previous owners) did some electrical work and didn't do it right at all.   I feel the need to be able to identify what's wrong in this house, electrical wise, and fix it.   We have a daughter and I don't want the house burning down.   A good example is the ground wire running to the gang boxes but not actually being hooked to the receptacles, not even the GFCI receptacles.   That's just not safe at all.   I went through and wired a pig tail to the switches and receptacles to fix that.

[Richard Crowley]

I'm going to be going to the ER later today and might not be back for a bit.

Our best wishes that they can diagnose the problem and solve it.

So, is there any danger with going for a larger breaker than what is actually needed? 

The answer that made sense to me was:  You must NOT over-rate the breaker for the wire gauge of the circuit. (Or conversely, you must not UNDER-rate the cable for the breaker current.  The reason given was that you want the BREAKER to "blow" under a fault condition, and NOT the wiring.  Because the breaker (or fuses)  are designed to safely trip/blow in a controlled environment.  But the wiring is running through your walls (or attic or basement, etc.)  And especially in domestic installations, it is not running through metal conduit tubing.  So overheating of the branch circuit wiring could actually set you house on fire if the breaker doesn't trip properly.

[Yansi]

So, just to be clear, so long as I purchase a 2P+E 32-amp receptacle, I can just wire the hots from a double pole 20-amp breaker, and run one of the hots to the neutral?    Or do I run one of the hots to the ground?    The receptacles I've been looking at for this have ground, neutral, line, where line is 240VAC.

It will make a nice bang if you connect a hot wire to ground 

Instead of hooking neutral to neutral, I'd hook neutral to 120VAC, then line to 120VAC, and ground to ground?   Using 12/2?

The device draws a good bit of current, but nothing insane.   7300KVA, or around 30 amp when running optimally (80% load).

The best way to think about things is to forget that "neutral" wires exist. Just consider all power conductors to be hot, and keep them well away from ground.

Note that a 20 amp circuit is no good for a device that will draw 30 amps or more. You will probably want a 35 or 40 amp circuit for that (with appropriate wire thickness and breaker).

In fact, neutral wire should always be treated as hot and never touched.

[IanB]

Sorry to hear about your health problems. I hope you get good answers from the doctors.

I know I can run 14 gauge wire on a 20-amp breaker.

I'm not so sure about that.

I know I can't run 12 gauge wire on a 15-amp breaker.

Why ever not?

The breaker is there to protect the wiring. If the wire carries too much current it can overheat and potentially cause a fire. The job of the breaker is to trip before that happens.

It really seems you should hire an electrician to do the work for you. As someone suggested above, have the electrician install a suitable NEMA socket in the wall (like a range outlet), and then have the electrician wire up an adapter cable with NEMA plug and IEC socket to go to your device.

[Spork Schivago]

The reason why the professional electricians can't accommodate the plug is that they're not allowed to wire in the European socket.  They must use sockets that are allowed for permanent installations in North America, which are pretty much NEMA sockets.  So have them wire in a dryer socket (30A) or a range socket (40A), then construct an adapter made with a dryer or range plug to your European socket. 
If you go out early on garbage day with a set of wire cutters, you can get the plug extra cheap. 

They can't do it because it's against the NEC?   As in I cannot legally do it either because it's against code?

This might explain the drastic price difference between the sockets over in Europe and the same sockets that say they're rated for North America.   The European ones are around 4 to 7 of their funky dollars (the L / F pound thing).   But the North American ones that I've seen are usually 100$ USD +.