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Components

Chris Cramer

Super User
Vendor
Premium Member
Hi, Does anyone have, a decent 2hp motor they could spare, or know of a good deal for a used or new motor? The motor I had installed on my 2x72 belt grinder shorted somewhere when I installed the single phase VFD, and now neither the motor nor the VFD works. I have a 2hp 3 phase motor and a cheaper 3 phase output VFD from Amazon I could use, but I have been planning on using that motor for a lathe.
 

TorontoBuilder

Ultra Member
Hi, Does anyone have, a decent 2hp motor they could spare, or know of a good deal for a used or new motor? The motor I had installed on my 2x72 belt grinder shorted somewhere when I installed the single phase VFD, and now neither the motor nor the VFD works. I have a 2hp 3 phase motor and a cheaper 3 phase output VFD from Amazon I could use, but I have been planning on using that motor for a lathe.
location?

BTW amazon sent me a single phase instead of a 3 phase vfd once and it bunrt out an indicator light on the tool and cutter grinder I put it on. It worked but caused issues with over heating. It took me a few minutes to realize what the issue was. Did you order a single phase vfd on purpose? They require changes to the capacitors IIRC... have you tried to diagnose the issue with the current motor, did you check if you friend the windings?
 

Chris Cramer

Super User
Vendor
Premium Member
Yeah shipping motors is expensive.
Anyway, the VFD that I installed was the one from ATO in the US that delivers a single or 3 phase output from a singlephase input. The way the capacitors were wired in side the motor was very tangled, so I didn't remove the capacitors I just used the L and N wires outsidethe motor. ATO says that the motor can be connected to any two of the three output terminals U, V, or W. I successfully set the settings of the VFD but when I ran the motor thr first time it caused a short within the motor.

The VFD from Amazon is a normal single phase to 3 phase VFD so I can only use it for my 3 phase motor. However I contacted ATO about a warranty claim an might get my hands on another single phase VFD.
 

Chris Cramer

Super User
Vendor
Premium Member
Ok, 1.5 hp could still be enough, in fact that is probably safer to use if I get a new 2hp VFD. I haven't gone deeper into the motor, if the windings aren't fried then I could pull all the wires and follow the model's wiring schematic to remove the capacitors.
 

DPittman

Ultra Member
Premium Member
Ok, 1.5 hp could still be enough, in fact that is probably safer to use if I get a new 2hp VFD. I haven't gone deeper into the motor, if the windings aren't fried then I could pull all the wires and follow the model's wiring schematic to remove the capacitors.
I'll check what I have. And just to clarify it will be single phase that I have.
 

TorontoBuilder

Ultra Member
Yeah shipping motors is expensive.
Anyway, the VFD that I installed was the one from ATO in the US that delivers a single or 3 phase output from a singlephase input. The way the capacitors were wired in side the motor was very tangled, so I didn't remove the capacitors I just used the L and N wires outsidethe motor. ATO says that the motor can be connected to any two of the three output terminals U, V, or W. I successfully set the settings of the VFD but when I ran the motor thr first time it caused a short within the motor.

The VFD from Amazon is a normal single phase to 3 phase VFD so I can only use it for my 3 phase motor. However I contacted ATO about a warranty claim an might get my hands on another single phase VFD.
a short within the motor is non-specific answer.

also with greater than a 1hp motor you have to remove the capacitors. Energizing both capacitors simultaneously can short both capacitors, and the VFD will do precisely that. So did you check if you have a short in either winding? and I mean with a meter?

Test the motor coils for continuity to ground, by performing a continuity test between the ground screw and terminal U1, and then between the ground screw and terminal U2. In both cases continuity should NOT be present.
 

DPittman

Ultra Member
Premium Member
That would be awesome.1.5 hp is most likely still enough power to run a 2x75 belt grinder. Even when operating it for heavy stock removal when bladesmithing, you don't have to put too much pressure on the belt which is what slows it down.
I'd think it would be well powered with 1.5hp.
 

Chris Cramer

Super User
Vendor
Premium Member
Perhaps this will help. There is a list of which types of single phase motors can be controlled.
Ah, that makes sense, that is making me think it may be best just to use my 3 phase motor with my 3 phase VFD. The motor I already had installed on my belt grinder had been working quite a while just off 240v, controlled with a power switch, and ATO had posted a video on how to wire and program the single phase VFD to run a single phase motor. If Tom has motor I could look at the capacitors and see if it can be wired without them, otherwise I'd use the 3 phase motor.
 
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