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softtail
06-22-2009, 01:51 PM
Hello all. I have this question into Bodine tech, but they are taking their time. So I'm switching a Delta band saw to metal. I have an 85 rpm ac 115/230 Bodine motor that I plan to run off 110. Will this thing require a capacitor? So far it doesn't work wired as per Bodine's schematic. I'm a newb at wiring...but I have a suspicion a capacitor is needed.

Thanks,

st

Evan
06-22-2009, 03:05 PM
It isn't a matter of just adding a capacitor. If it doesn't have one to run on 230vac then adding one isn't how you make it run on 117 vac. What sort of motor is it? What does it say on the nameplate?

J Tiers
06-22-2009, 08:44 PM
Very likely YES.

Please post pic of nameplate....... Most Bodine motors do need one, and usually if so will actually give the value of run capacitor that is required.

Wiring for 115 is generally simple, often shown on teh nameplate.

softtail
06-22-2009, 09:19 PM
Thanks guys. Yes Bodine got back to me and said I need one. I believe I have the one I need(375mfd, 110vac 60hz). Of course there's no wiring instructions on the Bodine site for the capacitor. From what I can gather, the two wires can go on either terminal on the capacitor, but what two wires those are(out of 6+gnd) I have no idea.

I've got the diagram on my desktop, and no web based picture service...

here's the motor page with pdf diagram:

http://www.bodine-electric.com/Asp/ProductModel.asp?Context=8&Name=48R%2DF+Series+Parallel+Shaft+AC+Gearmotor&Model=0693

st

J Tiers
06-22-2009, 09:57 PM
Thanks guys. Yes Bodine got back to me and said I need one. I believe I have the one I need(375mfd, 110vac 60hz). Of course there's no wiring instructions on the Bodine site for the capacitor. From what I can gather, the two wires can go on either terminal on the capacitor, but what two wires those are(out of 6+gnd) I have no idea.

st
Eh, look up the capacitor part numbers linked on that page...... towards the bottom.

I saw values MUCH lower than 375 uF....... more like 20 uF.

And follow the links on the page you linked to find wiring and installation diagram....

softtail
06-22-2009, 10:06 PM
Just figured out the symbol for a capacitor and got it wired up ala the Bodine diagram. Much better, but seems to spin too slow, and not constant.

According to the tech for 115VAC I need a 4 mfd capacitor.

The capacitor link on the bodine site from my motor has these specs:20.0 MFD / 370V; for 115V usage.

Anyone know which is correct?

Would the 375 mfd I have wired in there now make the rpm slow?

st

J Tiers
06-22-2009, 10:20 PM
The capacitor link on the bodine site from my motor has these specs:20.0 MFD / 370V; for 115V usage.

Anyone know which is correct?

Would the 375 mfd I have wired in there now make the rpm slow?

st

Yes, likely will make it slow, the phase shift will be hardly anything.

I have a 1/50 HP Bodine, which takes 3.75 uF, (about 4).... A larger motor, and I think yours is 1/3 HP, would probably take a significantly larger cap.

but then, some 3/4 HP motors I know of take 7.5uF, with the 1HP version taking 10. it all depends on the design.

softtail
06-22-2009, 10:24 PM
Thanks for you patience on this.. all Greek to me. I suspect one of the two is correct.. leaning towards what the web site tells me as opposed to the tech. I'll get it sorted tomorrow during business hours. It's been an education, thanks.

st

softtail
06-24-2009, 05:28 PM
The tech swears it's a 4mfd even though the site links to a 20mfd from the page for my motor. Evidently mine is 'special'. Have one on the way, and will report back.

st

Boucher
06-24-2009, 06:20 PM
The 375mfd capacitor is normally a start capacitor, is in a plastic can and only stays in the circuit for a short time say 20 ms. This requires some sort of switch to remove it. Most commonally a voltage relay. There are also current relays and solid state relays. Run capacitors (metal can) for motors from 1/4 to 1.5HP are typically 10mfd. There are different types of electric motor ie capacitor start induction run. Hope this helps and doesn't just add to the confusion. I have some of these capacitors if you need one or two. I would be glad to mail you some if would help. Grainger has allways had pretty good prices on this type thing. The motors that I am familiar with had three wires going it them Red, Yellow, and Black.
Red to Yellow is the start winding.
Black to Yellow is the run winding.

Hope this helps.

J Tiers
06-24-2009, 09:57 PM
It could be. That would be in-line with the values I quoted above for the HVAC blower motors.

Boucher:
The Bodine motors are usually "PSC" type, and need no start cap...... the run cap functions as both.

softtail
06-26-2009, 12:15 PM
I got a 4mfd in a metal can that makes the motor run perfect.. correct rpm, constant, no strange noise, no heat.

Learning the basics of electric motors, and getting some basic testing equip. has been added to the short 'to do' list. Already know quite a bit more than I did.

Thanks to this list/members for the help. I'll post pics of the finished saw.

st

softtail
12-05-2009, 10:48 PM
Finally had to get my rear in gear and get the bandsaw together for a project. Works like a charm.. spent most of the day cutting 1" steel rounds.. no problems. Thanks for all the advice.

st

J Tiers
12-06-2009, 01:30 AM
Good to hear back on it.... usually advice goes off into the blue. You pretty much did report back before, but now we know the whole thing worked.

Thanks

Doozer
12-06-2009, 01:54 AM
Bodines are the sweetest single phase motors around. Virtually no single phase hum and vibration.
--Doozer

softtail
12-06-2009, 10:51 AM
Yeah, I think I did ok on the motor I think, even if it did show up w/out a capacitor. Learned something, which is what it's all about. It was a 'best offer' deal on Ebay, and the guy took my low offer.. nothing to lose.

Still need to fab up an enclosure for the capacitor, and some table upgrades for keeping rounds from spinning, etc.

Really pumped to have a bandsaw in the shop.....

Thanks again,

st