Name that AC/VFD Drive--:)

[Drod04Mustang]

So this company has been in business for 50+ years and i guess noone told the previous electrician to "Do Not Throw Away Covers with pertinent information" here. I am trying to find a replacement for what seems to be a AC/VFD drive but there are no distinct markings or name on the device. Just wondering if anyone know what company or even what it is. Any help would be appreciated.

 

[petersonra]

Looks like a typical $30-50 small dc drive to me. Pretty much can be replaced by any other such drive.

 

[Jraef]

Looks like a typical $30-50 small dc drive to me. Pretty much can be replaced by any other such drive.

Yep. Single phase input, no visible output but far too few components to be an AC VFD. I too think this is a low cost analog DC chassis drive, like a KB Controls drive of the type often some to machine OEMs. Those often don’t have a cover, you may be looking at the entire drive.

KB and people like that make small chassis mount AC VFDs too, but again, not enough components there to be a VFD.

 

[Drod04Mustang]

I was leaning towards a DC drive as well. You guys are awesome. Thanks.. I figured ok. It has all these little dials that can be tweeked difference is it is not house with a small LED screen. But have never seen a DC drive so was unsure. Thanks for the info, i can now research this item further.

 

[ptonsparky]

How do you know it's bad and not the motor? Smoke release or voltage check?

 

[Drod04Mustang]

This issue is its hanging up every now and then. The employees move the pontentiometer up and it will go really fast(I have put the Accell and Decell turn knobs to the highest now so there is no wait time for changes to occur.) then go really slow without warning. I am getting 18-21 Volts on the output side of the drive to the motor. 28.57V into the line side from the power.

Motor seems fine no overheating. No smoke.

Possible Solutions:

Dont know if water got into the potentiometer and thats why its giving false output readings. Changeout?--Leaning towards this one now that I think about it.

New DC drive?

New Motor?

 

[zbang]

Especially with vibration, the pots can develop bad spots in the resistive part and jump around when moved only slightly; that's common in the volume controls of older radios, usually the it starts to sound "scratchy" when you change the setting. IMHO, find a replacement box. Well, find three because if one is failing the others probably aren't far behind.

 

[Drod04Mustang]

Now that we are running. I get 119 Volt on line side and 28.87 on output side. There is another DC drive exactly like this one but the wiring setup is totally different. input is 119 and output is 28.87 apprx. I will try. Thanks.

 

[Jraef]

DC motor may need servicing. One of the downsides of brushed DC motors is that they NEED routine maintenance such as brush replacement and commutator servicing, but that’s something that is often not done by people who don’t understand. So they are just run to destruction.

 

[zbang]

Granted (servicing), but for a small "drive" like that the motor is likely to be small, too, and even less likely to get more servicing than a compressed-air jet once and a while.

 

[Drod04Mustang]

Update.

Blew out with air blower, Re stripped all wires, and installed new potentiometer and EUREKA!!! Fixed. Way cheaper than a new DC drive, motor or anything else. Thanks to all.