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Joined: Mar 2005
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There may be an insurance issue. Here, if you have a fire and a BS 1363 receptacle and plug is suspected, the Insurer won't pay. They don't need much of an excuse to avoid paying anyway as I found out the hard way! [The ***** depreciated my electrical goods at 5% a month] As someone pointed out earlier, CE is not the same as UL, Norm Francais NF or a British Standards 'Kite' mark.


Wood work but can't!
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GregTaylor, even if I apply your interpretation, how on earth would an inspector catch it?

I ask this because the two SABC's can be served by a multi-wire circuit (share the neutral). 2008 code rules would then require the use of a 2-pole breaker - making it impossible to turn off just one side.

Breaker -> 240 receptacle -> first 120v circuit
. . . . . . . . . . . . . -> second 120v circuit

Assuming the 240v receptacle is serving the kitchen area, where's the code issue?

I don't like the plan, but I can't find the code to cite.

Noderaser, you nailed it: in those antique buildings, every tenant has their own transformers, or has had to obtain special equipment.

Why don't they upgrade the buildings? That often goes back to the original manner of construction. One of the buildings I referred to is known as the 'first' skyscraper - a massive, solid masonry 10 story building. You don't easily change such things.

Last edited by renosteinke; 08/14/10 11:35 AM.
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Reno, if this was my patch I would just cite the first line of 210.52

"210.52 Dwelling Unit Receptacle Outlets.
This section provides requirements for 125-volt, 15- and 20-ampere receptacle outlets."

A 240 v outlet would be "other" (as in "no other outlets").

I can ask this over at Fl IAEI but I bet there isn't a CBO in Florida who would not agree with me.


Greg Fretwell
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It might be worth getting a 'formal' interpretation. After all, the coffee maker we're discussing is most certainly a counter-top appliance. I note that the 'exceptions' to the 'no other outlet' rule are both items that are not appliances that you might set on the counter.

You're citing 210.52 B 2. Perhaps we're better served by 210.50 C, which provides that receptacles intended for specific appliances be mounted near that appliance. It's a bit of a stretch, but since they illustrate their point using laundry equipment as an example, perhaps we might infer that they assume that a receptacle for a specific appliance would have it's own dedicated circuit.

We also have 210.21 B 2, which addresses the maximum cord-connected load for a circuit. If that coffeemaker gobbles up all the power, you can't really add more receptacles to the line, can you? (Be wary of this one, though ... think of all thos microwaves, toaster ovens, and bread machines!)

Looking at 210.11 C 1 (where the two SABC requirement is), it occurs to me that a 240v circuit, supplying a 240v receptacle, is but ONE branch circuit. Split off 120 'legs' all you want, it's still ONE circuit. With the 240v receptacle, we can't call it a 'multi-wire branch circuit.' I think that's the section we need to cite.

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djk Offline
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From a purely technical and practical perspective, either Schuko or BS1363 would actually perform perfectly well on a US 240V supply.

From a safety perspective, either of those plug/socket systems are beyond what UL would mandate although they do not have UL certification as they are not intended for sale in the USA.

Unlike NEMA outlets, both CEE 7/X and BS1363 provide standard finger protection to prevent shock.

Schuko (CEE 7/X) does this using recessed socket outlets and a standardised plug body shape that keeps the pins entirely out of reach when you are inserting/removing the plug.

BS1363 (UK/IRL system) uses sheathed pins.

The big issue with using these plugs in the US is that they are not likely to be approved by the US wiring codes, even if they are excellent standards.

BS1363 (UK/IRL) does however expect to see 230V on Line and 0V on neutral. Some 'switch sockets' would only isolate the line and not the neutral, although double pole versions are available. Also, if the fuse blew in the plug, it would not isolate the neutral.

Your local regs may have issues with CEE 7/7 sockets (Schuko) as they are not polarised. However, with a US 240V supply, both sides are hot anyway, so it makes very little difference in reality.

We have issues using NEMA plugs in Ireland for 110V as they are not approved by a recognised standards body here. The unsheathed pins also prove an issue.

I'd say if you're going to install a 240V socket, use whatever NEMA equivalent you can find to comply with the code.

If you opt to install BS1363 or Schuko (CEE 7/X) you will be perfectly safe, but you will have probably breeched the wiring code by using non-US-approved fittings.

Last edited by djk; 08/15/10 12:10 PM.
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DJK, thank you for your replies; as usual, you bring a wealth of detailed knowledge into the discussion.

I don't think there is any requirement here that plugs conform to any particular pattern, or be "UL listed."

Apart from the usual pattern we see on 'ordinary' plugs, most of us have a completely differrent 120v receptacle and plug on the power supply to our laptop computers; even desktop computers use a different pattern. Various industrial controls have proprietary plugs as well - even when the thing needs but ordinary 120v.

Therefore, I don't think there is any US code issue with using a Euro-style receptacle to accept a Euro-style plug- as long as the power available is appropriate for the device.

As I see it, the only code issue was the proposed method of deriving this 240v from two separate 120v branch circuits.

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You can still bump up against 110.2 "Approved" equipment.
Overwhelmingly that ends up meaning "listed".
That is a big issue now in Florida with solar equipment where the AHJs are saying, "if listed equipment exists, you will use listed equipment".
We saw that here with the water bonding device thread.


Greg Fretwell
Joined: Mar 2005
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Steve - Now you're sort of changing the question. Will an inspector catch it? Only if you buy a permit and show it to him, but that's not what you asked.
We all know we can make things work with out-of- configuration pieces/parts if thats all that is at hand, and we can also do things that work and even slide them past inspectors sometimes (I've never, ever done this). I'm sure that what you propose will run your coffee pot and small appliances perfectly well and probably with no danger to anyone, if done carefully, but I still don't think an inspector would sign off on it, and he would probably cite 210.52(B)(2)

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djk Offline
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The only other thing I would add is that I'm not entirely sure if the US 240V 60Hz peak voltage would be within the safe limits for a 230V 50Hz European appliance.

Do you know what the normal voltage range one would expect to see at a US 240V outlet is ?

If it's a simple coffee pot without any electronics on board, it will be unlikely to know the difference. However, if it's a modern espresso machine or anything with a lot of electronics on board the US supply might fry its electronics or at least reduce their life span substantially.

I know I have heard some weird problems where people have installed European washing machines on US 240V supplies i.e. electronics have malfunctioned. There can be quite a surprising amount of electronics in modern Euro washing machines not only the cycle controls but also solid state controls for variable speed drives which may be quite sensitive to not getting exactly their rated voltage and frequency.

I'd say if its a simple coffee pot though, you've very little that can go wrong laugh

Last edited by djk; 08/17/10 11:16 AM.
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Greg- it would work and would be safe from a shock/OCP perspective, but it's a terrible design, one that would lead to nuissance trips, and one I'd certainly never put my stamp on. Seems from this discussion that the legality is a gray area, depending on how the AHJ interperets a couple codes. I really can't see anyone ever approving something like this. Was an interesting discussion, though.

djk- The issue for the washing machines was probably the motor. 50Hz DC rectifiers work great at 60Hz, better than at 50Hz (the reverse is not true), so electronics shouldn't be impacted. Tuned harmonic filters could be an issue, but they're not very common in appliances. Transformers may heat up a little more if the plate laminations were designed for 50Hz, as 60Hz needs thinner laminations to mitigate hysterisis losses, but it would be a fairly small heat gain- not like the fire you'd start if you put a 60Hz transformer on 50Hz and saturated the core.

The big problem I see for a 50Hz washer on 60Hz power would be syncronous AC motors. If they're designed to work at 50Hz, they'll spin 20% too fast at 60Hz, and I can see that causing quite a few issues in washing machines, food processors, etc.

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