EEs Needed - Help with a DC Motor

[Mylo]

Alright, I jumped the gun on a DC motor on eBay for my mill. I didn't realize that it was DC when I bought it. Now I need to find some DC motor control. The motor that I bought is a DC Shunt motor. The sales lady at Bodine tells me that both the field and the armature run at 115 VDC. It's actually a very cool form factor (right angle).

I'm trying to keep the total costs down on this thing. I don't really need reversing or even variable speed - but it looks like I might get it. I found a "bare chassis" controller. Problem is the max field voltage is 100 and the max armature is 90. Does that mean that the max speed will just be a little lower? I don't want to burn this thing up. The necessary amperage is only something like .68A.

Here is the one I found: http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... :IT&ih=010

or, would it be better for me to hold out for something like this: http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... :IT&ih=007

Any help is greatly appreciated. Thanks.



Mylo

[acr4]

EE here, but I do software and semiconductors, not DC motors... My guess is you can run the guy a little slower w/ lower voltage and no real harm will be done. Anything over 12V scares me. Please consult an electrician or old-school EE before believing anything I say though.

[BadRock]

Given the amount of time you are going to run this at the reduced voltage you will not have any problems. As long as the controller can handle the rated current you are fine, which it looks like the cheaper one will.