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Help with 3hp WEG VFD

TravisR100

Cast Iron
Joined
Aug 7, 2006
Location
Houston, TX
I'm a novice when it comes to VFD's. I'm helping a neighbor hook one up. He has an older 3hp 3 phase motor. Data plate...
IMG_4485.jpg

The VFD is a WEG CFW300B10P0B2DB20. Link here...
https://www.automationdirect.com/ad...requency_drives_(vfd)/micro/cfw300b10p0b2db20

I went through the basic setup from the manual...
Copy.jpg

With the P002 parameter selected I push the run/stop button and the motor starts to turn but the display shows 2 hz and fluctuates slightly up and down from that. I set the minimum to 6 hz and the maximum to 66 hz. I press the up button and run it up to 66 hz but when I let go of the button it reverts back to showing 2 hz and the motor is turning at what I'd estimate it would turn at 2 hz. In other words, very slowly.

Any clues?
 
Also, I'm feeding this 220 single phase and using only the L1 and L2 terminals and leaving L3 disconnected. This particular model is capable of 1 or 3 phase input.
 
I set parameter 202 to VVW instead of VF and went through the auto tune procedure. Didn't make any difference. I'll also note that this model is both single and 3 phase input rated so it has terminals L1, L2, and L3 on the input side. Since I'm using single phase I only hooked up L1 and L2. Don't see that there's any parameter or way to tell it that I'm only using single phase however.
 
Don't think your issue has anything to do with L1 and L2.

I have to read my manuals more than once. Writing up cheat sheets makes the learning go easier.
 
Thanks for that link. Haven't seen that quick start guide before. Definitely better than the official WEG documentation. I did find and fix the problem. Parameter 404 is the motor HP rating. I set it to 3 for a 3HP motor. 3 is actually for a 1/2HP motor. Needed to be set to 8 for a 3HP motor.
 
Definitely better than the official WEG documentation.

I have the same drive on my lathe. The documentation stinks. I sat down with the folks that are responsible for the documentation and gave them an earful. They could not defend their position once I was done with them.

The drive itself is pretty cheap and is not half bad.

Hopefully they will improve the documentation on future projects.
 
Was the drive brand new when he bought it? If not, ALWAYS go through and do a reset to factory defaults, you have to get rid of all previous programming or you end up chasing your tail forever. If you are unsure of what you did yourself, that's also a good option. Start fresh.
 
I checked a 3hp motor here. The plate says for FLA:
230V - 5.4A
460V - 2.7A

I think he was referring to the drive's programming number.

0 = 0.16 HP (0.12 kW)
1 = 0.25 HP (0.18 kW)
2 = 0.33 HP (0.25 kW)
3 = 0.50 HP (0.37 kW)
4 = 0.75 HP (0.55 kW)
5 = 1.00 HP (0.75 kW)
6 = 1.50 HP (1.10 kW)
7 = 2.00 HP (1.50 kW)
8 = 3.00 HP (2.20 kW)
9 = 4.00 HP (3.00 kW)
10 = 5.00 HP (3.70 kW)
 
I think he was referring to the drive's programming number.

0 = 0.16 HP (0.12 kW)
1 = 0.25 HP (0.18 kW)
2 = 0.33 HP (0.25 kW)
3 = 0.50 HP (0.37 kW)
4 = 0.75 HP (0.55 kW)
5 = 1.00 HP (0.75 kW)
6 = 1.50 HP (1.10 kW)
7 = 2.00 HP (1.50 kW)
8 = 3.00 HP (2.20 kW)
9 = 4.00 HP (3.00 kW)
10 = 5.00 HP (3.70 kW)

Correct.


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