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#208697 - 02/06/13 07:25 PM 230 Volt machinery on 208 volts
bossanova5 Offline

Registered: 10/26/12
Posts: 13
Loc: L.A. CA
Hello All,

I'm doing a major machine shop move.The old building was a 240 volt service,the new one is 208 volts.

I have four older CNC machines designed to run on 230 Volts.I'm right on the 10% voltage threshold (207 volts)

According to the Manufactuer's of the machines 208 is ok.

I'm wondering what the long term effects will have on the motors and what experience you guys have encountered with this situation.

Thanks in advance

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#208699 - 02/06/13 09:13 PM Re: 230 Volt machinery on 208 volts [Re: bossanova5]
twh Offline

Registered: 03/11/04
Posts: 895
Loc: Regina, Sask.
The overloads will protect the motor from negative effects.

#208700 - 02/07/13 06:28 AM Re: 230 Volt machinery on 208 volts [Re: bossanova5]
HotLine1 Offline


Registered: 04/03/02
Posts: 6791
Loc: Brick, NJ USA
Had no previous issues with any equipment during my days with tools.

A few occasions I had to install buck-boost transformers for some equipment that required 230/240 is a 208 system.

#208705 - 02/07/13 01:52 PM Re: 230 Volt machinery on 208 volts [Re: bossanova5]
Tesla Offline

Registered: 06/16/04
Posts: 1280
Loc: Sacramento, CA
Resistive elements draw less current, less power.

Inductive motors produce less back-EMF, draw more current; which nets out to s l i g h t l y less power, a tad more rotary 'slip.'

Unless the motor controller has voltage sensing -- which would object -- induction motors will tolerate the 200-230 VAC ( or 208-240 VAC ) range without much fuss.

Heater overload elements might require swapping out, though. Check the schedules provided by the NEMA players.

Edited by Tesla (02/07/13 01:53 PM)


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