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Can autotransformer be used for distribution?

1306 Views 13 Replies 5 Participants Last post by  Breakfasteatre
Can I use a 600/208 autotransformer for distribution? I have 347/600Y supply coming to a machine shop and need to step down to 120/208y for 400 amp 3-phase panel. 150 KVA autotransformer is readily available. Rule CEC26-266 2(a) seems to say I can and i can't. I do have a solidly grounded neutral available from the primary feed. Is this setup acceptable in Canada?
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the code rule is 26-264 (2)

and you need to satisfy both (a) and (b) or (a) and (c)

so you have satisfied (a), but do you satisfy either (b) or (c)?

the auto trans is used for starting or controlling an induction motor


the auto trans supplies a circuit wholly within the apparatus that contains the auto trans
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