Selecting a VFD for a Harrison lathe.

[not done it yetParticipant @notdoneityet]

One could always check the current on the VFD input side for power drawn (assuming a % efficiency for the whole lot). But that may not show a great deal as the motor is basically idling. It would appear that one phase is fighting the other two when supposedly wired delta.

At full load a star 415V motor will only produce about 60% rated power, if driven at 230V.

Edited By not done it yet on 06/01/2019 23:10:04

[Robert Hurst 1Participant @roberthurst1]

Is it possible to scroll through the VFD menu and read the DC bus (or link) voltage?

Cheers, Rob.

[Daniel GrantParticipant @danielgrant15006]

When I went to collect the motor the chap I was buying it from couldn’t get it started with a capacitor, so wired U1 to neutral and V1 and W1 to live on a standard single phase supply. The motor hummed for a few seconds then went silent. Could this have burnt out one set of windings? I was hoping the resistance test would highlight if one set was damaged, but they all had the same resistance.

I’m a little concerned that I’ll bore out this pulley, then find out it won’t work under load.

[John HaineParticipant @johnhaine32865]

If a winding had burned out there would have been a "loud brown smell" and it would have taken more than a few seconds. More likely a fuse. Your resistance test is a better guide. I have a feeling that when it was delta connected one of the windings was backwards and that has been corrected in your star connection.

[Daniel GrantParticipant @danielgrant15006]

Thanks again for all the input everyone. I've taken the plunge and bored the pulley out to fit the new motor. Hopefully I'll have some time tomorrow to try cutting the keyway into it.

John, I'll try and find the forum posts you mentioned earlier regarding the potential for a motor winding to be backwards.

[Daniel GrantParticipant @danielgrant15006]

Just a quick post to thank everyone for ther help with my VFD issues. I have just returned from a good few hours turning my first test project on the Harrison and am really pleased with how its working, still getting used to all the dials, but loving having it up an running.

[EmgeeParticipant @emgee]

Thanks for the update, pleased to hear you are working the VFD and motor.

Emgee

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