Re: [CAD_CAM_EDM_DRO] Re: Phase converter for CNC lathe

You could try installing a voltage regulator that will hold the line voltage
to whatever the machine calls for.

Smoke

>Randy,
>
>Interesting what you say about the European motors. I have an Emco
>Mairer (sp?, I should've learned to spell it by now) CNC lathe which
>I purchased new 14 years ago. My purchase was with the guarantee it
>would run off an Arco phase converter that I already owned. The
>spindle motor is rated around 6 hp. It runs fine most of the time,
>except when our line voltage drops, like around dinner time. Then
>the machine errors out, with a "spindle drive not ready" message,
>which translates to, "shut down for the day and come back tomorrow".
>For whatever reason they set these machines up to be very sensitive
>to incoming voltage, but that sensitivity only affects the spindle
>motor, everything else works in a low voltage condition.
>
>Like other European machines I've seen this one came with a multi-tap
>transformer because it runs on 380V, 3 phase. You can switch the
>transformer leads around to get it to run with most any line voltage
>condition, we've setup for the most common line voltage which is
>fairly steady from morning to late afternoon. Incidently, forget
>about even trying to run on Thanksgiving or Christmas.
>
>Doug
>
>
>
>--- In CAD_CAM_EDM_DRO@y..., cnc002@a... wrote:
>> In a message dated 4/30/01 10:48:27 AM Eastern Daylight Time,
>
>>
>> Doug:
>>
>> I agree with that assessment. When I worked for a large
>woodworking
>> machinery manufacturer we would not warranty any three phase
>machine with a
>> motor over 10 HP if used on a phase converter. The reason being
>that the
>> machinery was Italian and European three phase motors are NOT made
>to the
>> same specs as ones made here in the U.S. That is not to say they
>are in any
>> way inferior, in fact the specs on them were tighter and therein
>lay the
>> problem. They would not accept as large a voltage swing as the
>U.S. motors
>> do. Because of the negative experience we had with the converters
>on
>> machines over 10 HP it was decided by the powers that be to put a
>disclaimer
>> on the warranty. Also, the startup load is very important in
>choosing
>> whether to use a phase converter at all or not and in choosing the
>converter
>> itself if the decision is made to use one.
>>
>> Regards,
>>
>> Randy Abernathy
>> Woodworking Machine Specialist
>> 4626 Old Stilesboro Road NW
>> Acworth, GA 30101-4066
>> Phone/Fax: 770-974-5295
>> E-mail: cnc002@a...
>>
>>
>> [Non-text portions of this message have been removed]
>
>
>Welcome to CAD_CAM_EDM_DRO@...,an unmoderated list for the

discussion of shop built systems, for CAD, CAM, EDM, and DRO.

>
>Addresses:
>Post message: CAD_CAM_EDM_DRO@yahoogroups.com
>Subscribe: CAD_CAM_EDM_DRO-subscribe@yahoogroups.com
>Unsubscribe: CAD_CAM_EDM_DRO-unsubscribe@yahoogroups.com
>List owner: CAD_CAM_EDM_DRO-owner@yahoogroups.com, wanliker@...
>Moderator: jmelson@... timg@... [Moderator]
>URL to this page: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO
>bill,
>List Manager
>
>FAQ: http://www.ktmarketing.com/faq.html
>
>Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>