US 208V L1-L2 to UK 220V L-N

tortuga said:
Are you 100% sure about this?
My understanding of the regulations over there is they always have to use a double pole switch, because while they standardized on 230V because its simpler :) they allow many different grounding schemes (earthing systems) so blue is not guaranteed to be a 0 volts to ground and should never be treated that way, for example a IT earthing system in countries like Norway would have both blue and brown 'hot' with respect to equipment ground.
I have seen lots of 220V - 230V 50/60 hz labeled EU equipment work great off 208 - 240 (Line to Line) but it wont tolerate 277 don't ask how I know.
A 208 to 240 isolation transformer would be a waste of money and 24/7 vampire load.
Where does your responsibility end? A receptacle ? A disconnect?
If they don't have a 2 pole switch on their rack, just throw a standard disconnect within sight and call it a day.
Click to expand...
Here is a partial of their schematic. None of the blue wiring is switched.
I feel like if I just have them change all the 1-pole breakers to 2-pole breakers then all would be good in the code and safety world?
But providing them a 208V with a bonded neutral would also work too?

I guess its 6 of one and half-a-dozen of the other.

I would do that and call it a day, but I have the maintenance contract on this stuff and have to watch out for my guys safety too.
 

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electrabishi said:
Here is a partial of their schematic. None of the blue wiring is switched.
I feel like if I just have them change all the 1-pole breakers to 2-pole breakers then all would be good in the code and safety world?
But providing them a 208V with a bonded neutral would also work too?

I guess its 6 of one and half-a-dozen of the other.

I would do that and call it a day, but I have the maintenance contract on this stuff and have to watch out for my guys safety too.
Click to expand...
Huh interesting I wonder if thats a drawing mistake it says A9P54606 which is a common Schneider 6A din rail mount breaker and the ones I have seen break the neutral, they may not have over current trip device in the neutral but I thought they disconnect both.
Well now you got me wondering I'll have to check them next time I see one!
 
I just checked and the A9P54606 does disconnect both lines but does not protect the 'neutral'. Since thats a 2nd line in the US 208V use case to provide 2-pole 6A overcurrent protection with the 'B curve' ask them to provide a M9F21206
If its necessary.
 
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I would be fine if it actually disconnects both lines.
I'm not stuck on it needing to have overcurrent protection on both, just so that if one trips or if a tech turns off the circuit, both lines are opened.

The M9F21206 would work except the 2 pole version is double wide and I'm space limited. The A9P54606 is only single wide. But I'll actually check it. If it breaks the neutral then I'm good already. I didn't even think to check it. Just went by the drawing they provided me.
 
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