Single-Phase Power and Three-Phase Frequency Drive

For most small ones under a few horse power (2kw) yes. Bigger units typically will need the rectifiers beefed up and the capacitor banks doubled for full output ratings on single phase inputs. The rated input amps will be much higher too so factor that into the supply wiring.

I have done this to a number of them from .5 hp up to 15 hp and never had any failures even with long term use.

But again not all VFDs are capable though.

I've got 4 lift stations set up that way, three with two 2.5HP pumps and one with two 10HP pumps. We use ABB drives and have had no problems whatsoever. Using VFDs to generate a third leg will require you double the HP rating of the motor when you size your drives.

Minor correction: it requires that you double the size of the VFD with respect to the motor size, not double the size of the motor. For example, if you have a 15HP motor, you would buy a 30HP VFD so that the front-end conversion section is large enough to handle the extra current that will be drawn from the 1 phase source, as well as the added bus capacitance to handle the increased ripple caused by the less continuous power flow with 1 phase.

As mentioned earlier, most VFDs 3HP and under will accept 1 phase input without over sizing the drive, they are built with enough extra capacity to do the job. The doybling rule only applies above 3HP.

No, it must be a single phase freq drive with a 3-phase output.

See previous discussions regarding this....

You have to consult the VFD manufacturer to find out if that specific VFD can do it. As has been stated at "lower" HP rating drives are udually capable of this. Depending on the size of the connected motor the VFD may have to be oversized to work in single phase mode. But this is also manufacturer specific and there are no hard and fast rules for every VFD. Just know that is it possible but you have to research the VFD you plan to use to get the right piece.

Shawn

With not knowing the manufacturer of the drive, please take this as a general answer.

The drive lines that I represent allow you to run on single phase power with a 50% derate. You should be using a 240/3/60 drive on your 240/1/60 power.

I would recommend that you contact the drive manufacturer and request the exact load the drive will handle on single phase power. I do this each time I need to do this.

Hello DK,

Try:

www.phaseperfect.com

We have had great success with these units, the power is true three phase with no derating.

Much less complication.

Just make sure whatever you use, the single phase supply is adequate.

Yes, depending on the HP you can use a single phase source to power a variable frequency drive. The range of motor sizes that you can use is limited and depends on the manufacturer of the drives. Try the Danfoss VLT2800 drives. The VLT can go from 0.5 to 3.0 HP for single phase supply.

Have specified this drive:

http://www.cerusindustrial.com/templates/product.asp?ProductGuid=CI-003-C2-1P&GroupGuid=40

for cost-effective VFD in that application at 3hp motor

...they have smaller drives available for smaller motors.

Above 3hp jumps to larger series with heftier components to perform this same function.