best way to convert 400 VAC environmental chamber to 480 VAC

[cambria]

I am considering purchase of an evironmental chamber that is 400 VAC 50 hz. I have 208 and 480 VAC in the shop. The chamber basically is an oven and a refrigerator, so lots of stuff including control electronics.

If it was a simple device the 400/50 matches up with 480/60hz, but it is not so simple.Whats the best approach? Variable Freq drive, transformers, or simply dont bother?

 

[waross]

Transformer for the oven, VFD for the motor.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[cambria]

That requires me to dig in a separate lines, I suppose I can do that, sounds cumbersome. The VFD wont do the whole deal?

 

[JohnWaa]

It should. You would just have to purchase a bigger one.

Although, I don't know how a VFD would respond to driving an oven...

 

[wayne440]

You could do it the old fashioned way with a rotary converter. 480v/60hz to 416V/50hz is a common spec.

Unless you are getting a very good price on the unit, or there is some other equally valid motivation, you might be better off to pass on this one and locate a chamber that works on the voltage you have available.

 

[jraef]

VFD would not be a good option for the entire system. Transistor based systems do not like sudden changes in load, i.e. a heater contactor switching on and off. If you use an SCR power controller for the heater, it will not like being fed by the PWM output of the VFD.

Your real choices (other than finding one built for US power) are to separate the systems as previously suggested, or the M-G set approach.


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[cambria]

Well it sounds like the best thing to do is forget it. The original idea was sound, but the power issues are not simple, and yes, by the time one is finished with all of the converters you are into thousands just for the power.

Thanks for the input, better to stop this train before it goes over the cliff...