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#101274 - 03/02/07 08:00 AM auto xfmers questions
Reel-Break Offline

Registered: 04/04/02
Posts: 179
Loc: nc
Hey we have a dicussion here in the shop. I`m wiring a machine 380 volts 3phase. Well The rated kw reads as follows 380@70kw max.
I get 2 25kva xfmers and wire per 575/380 output my total figured kva is 103. Ok that`s my total avalible if needed.Co-workers maintain I should figure wire size and ocp according to 103 but I`m only using 70 of the 103 and plan on sizing accordingly.Also now here`s one thing we`re all unclear about in the auto configuration would we say 70kw/380x1.732=106amps
or use 70kw/575x1.732=70amps? Thanks in advance.

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#101275 - 03/02/07 11:14 AM Re: auto xfmers questions
Reel-Break Offline

Registered: 04/04/02
Posts: 179
Loc: nc
I`m thinking that the voltage is 380 to the machine so I`m planning on going with 106amps calc. 125 ocp 1/0 wire thhn.

#101276 - 03/03/07 12:43 PM Re: auto xfmers questions
Redsy Offline

Registered: 03/28/01
Posts: 2138
Loc: Bucks County PA


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