1PH supply to a 3ph vsd
1PH supply to a 3ph vsd
(OP)
I have a 3phase VSD for a pump, but only have a 230v supply, is it possible to run the pump through the vsd with a single phase supply?
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RE: 1PH supply to a 3ph vsd
You also need a VFD that doesn't care about missing phases. It has to be larger than normal.
Keith Cress
kcress - http://www.flaminsystems.com
RE: 1PH supply to a 3ph vsd
RE: 1PH supply to a 3ph vsd
You will want to make sure the VFD is capable of 1PH operation, and you will also be required to roughly double the size of the VFD to accommodate the loss of the third phase. (5HP motor takes a 10HP drive, etc.) I know that for VFDs such as the Allen-Bradley PF40 series, this is commonplace.
One other thing I commonly have to be cautious around when doing this are delta secondaries, be it a 240/120 with a wild B phase or a 480V corner grounded or open delta. VFDs like to see some balance on the inputs; if at all possible make sure you're on a properly grounded wye system when doing this.
RE: 1PH supply to a 3ph vsd
I connect my single phase supply to my R phase on the supply of the VSD and loop out my other 2 phases. Applying the same for the secondary and send the single phase to the motor.
The motor is 4hp.
RE: 1PH supply to a 3ph vsd
Connect the two line leads of the 1 phase supply to two of the three input terminals. Most VFDs don't care which two, some require that it be L1 and L2. Don't "loop" anything!
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RE: 1PH supply to a 3ph vsd
xnuke
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RE: 1PH supply to a 3ph vsd
Xnuke is right, you can't use only 2 phases off of a 3 phase VFD, it will trip on unbalanced output current. Then there is the other big issue of using 1 phase motors on VFDs at all, which can touch off a lengthy debate in this forum.
My "Reader's Digest" version: only a select few types of 1 phase motors can be used with VFDs, and the VFDs are specially designed for that purpose. You don't use 3 phase VFDs for the few types of 1 phase motors that can be operated by them.
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