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Discussion Starter · #1 ·
I posted earlier about renting some shop space with 3 phase power and have found out that there's a "rare 240/480v three phase Delta service with owner supplied neutral" in place as per the power company. They no longer provide these services and will supply the existing ones because they have to. They won't re-supply the building with the current 208-230/460v service because they consider it a service change and will require that the meter(s) be moved to the outside of the building(currently inside), change of transformers etc,etc. The landlord doesn't want to bear the cost at this time either. I have a few concerns about the motors on my saws, planers etc. Does anyone out there have any experience with this type of service?
 

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Contractor of the Month
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The 64K$ question is what equipment do you have?
 

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Discussion Starter · #3 · (Edited)
3 phase-
Oliver 270 5hp 208v
Oliver 232 3hp 208v-( both these saws have an electronic motor brake wired in)
Oliver 91 mortiser 220v
Oliver 399D planer 3 hp 220v
Northfield Production Shaper 7.5 hp 208v
2-Delta Unisaws, 1.5 & 3 hp
Single phase, 230v-
HolyTek shaper 5hp
Delta 40B Multiplex RAS 2hp
Rockwell 22-401 planer 3hp
Delta 20" bandsaw 2 hp
Crescent 12" jointer 5hp

Plus a bunch of 115v stuff
I'm not too worried about the single phase stuff, but this 2 wire, "Delta" 3 phase with a ground for neutral has me a bit confused.
 

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The Ultimate Wire Hider
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This suggestion is a little over my pay grade but perhaps you can get a couple of small step-up/step-down transformers just for your items that run on 208. We do all the time for computer equipment that comes from Europe requiring 220 volts single phase.
 

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My first, second, & third shops were all 3ph 230v (230-240V...VARIES), with an additional single phase service meter for the 220 single ph, & 110 lighting ect.. 3ph motors don't need a neutral to run. They just need to be safety grounded. The service feed neutral is for adding single phase service without an additional service meter.

At least that's the way I understand it. Hopefully a sparky will chime in to read me the riot act!
 

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So you have a service like this:



But instead of a center tap like so you have a separate neutral wire?

 

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As far as the motors are concerned, it's all the same. l1 l2 l3 leads go to the motor. It's 220v across one lead to the other. Then you just safety ground.

The neutral has nothing to do with 3ph motor leads. That is for doing single phase (110, & 220v single ph) service with just one 3ph supply meter. You just use one 3ph leg, & then use the neutral to get single ph., but the voltage would still be run through a buck/boost transformer to get the 110v.
 
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