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Pete Keillor Pete Keillor is offline
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Default 3 phase rotation direction?

On Wed, 26 Jan 2011 15:27:46 -0800, Winston
wrote:

Pete C. wrote:

Winston wrote:

Pete C. wrote:

Winston wrote:

I Googled but didn't find anything that would
work quickly.

Who makes an inexpensive tester that I can plug
into 208 V 3 phase L14-30 outlets to determine
phase rotation?

I'm aware of this circuit but I want something
I can buy at the Borg and leave at a worksite:
http://www.opamp-electronics.com/tut...on_2_10_03.htm

--Winston

You won't find one at the Borg, since they don't carry anything three
phase. You will find them at most any real electrical supply house for
~$100 or so. The good thing is that those phase rotation meters usually
also include motor test functionality so you can identify the leads from
an unpowered three phase motor as long as you can manually turn it more
than half a turn.

It helps to know the proper nomenclature.
Good info. Thanks!

--Winston


One additional note is that there aren't too many three phase loads
you'll run across that will be harmed by running reverse rotation for a
couple seconds, so most of the time you can just blip the load on and
see if it's running the correct direction, and if it isn't swap two
phases before trying again.


That is exactly what did.

I laughed a lot when I saw that the rotor was running backwards.
It instantly explained much of our problem with water flow.

A true 'head smack' moment.


Otherwise known as the engineer's salute.

Pete Keillor

Thanks again, Pete.

--Winston