Author Topic: Phase converters  (Read 1343 times)

Offline smiffy

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Phase converters
« on: October 13, 2016, 02:44:45 PM »
I have a 80amp supply into my workshop .What would be the largest 3 phase motor I could run allowing for start up loads and which type of  phase converter is best, digital rotary or static . At present I have both static and digital but largest motor is 5 horse.

Just fancy a Dean Smith and Grace lathe but before I start looking need a good idea of what is practical  or suggestion on any lathe with a 50 mm or bigger headstock bore and about 6 foot between centers . Mike

Offline Jo

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Re: Phase converters
« Reply #1 on: October 13, 2016, 03:32:08 PM »
If you look to fit a rotary transformer converter it would happily run a 15hp motor on a 80A supply  :ddb:

Jo
So many engines to build and yet so little time.

Offline PK

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Re: Phase converters
« Reply #2 on: October 13, 2016, 06:38:29 PM »
You can work it out:

      Volts x Amps x Converter Efficiency = 2 x Motor rating

The 2 x motor rating is to allow for startup loads. You can reduce this factor if you have slower rated circuit breakers http://www.diynot.com/wiki/Electrics:MCB2

Not sure about rotary converters, but their solid state brethren run at about 80% (as a budgetary figure).

So you have 220 x 80 x 0.8 /2= 7KW = 9.4HP

PK

Offline awemawson

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Re: Phase converters
« Reply #3 on: October 14, 2016, 02:54:15 AM »
I did blow the 80 amp company fuse with my 15 kW Transwave converter but it wasn't the only thing running. The nice man who came out on the emergency call out uprated me to a 100 amp fuse when I showed him my workshop.
Andrew Mawson
East Sussex

Offline smiffy

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Re: Phase converters
« Reply #4 on: October 14, 2016, 08:07:46 AM »
Thanks for the replies. Just need to crack open the piggy bank and think I will go down the rotary converter route  Mike

Offline graham

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Re: Phase converters
« Reply #5 on: October 22, 2016, 03:05:21 PM »
Give this firm a bell,got mine off them brill.http://www.drivesdirect.co.uk/