Want to buy DC motor

Give these folks a try.

Strange, but I've never heard of a "single phase" DC motor - or even "single phase" DC power, but wadawino?

Any place that sells step-aside transformers will have them.

Kevin Gallimore

PM brushless DC motors are essentially polyphase synchronous motors, so someone (but not me) could argue that they are 3 phase DC motors.

Ned Simmons

By single phase, I mean that I'm currently powering my mill with 220 volt, single phase power in my shop. Just trying to narrow down the type of motor that I want.

-- Johnny Stout Handmade Knives

Out of curiosity -- is there any particular reason that you are rejecting the idea of a three-phase motor and a VFD? depending on luck of surplus purchases, the combination may cost you less than a DC motor of adequate quality -- and you don't have to worry about replacing brushes every so often.

Good Luck, DoN.

I need a single phase, 1.5 hp, 180 volt, 2500 rpm, 56C frame, 5/8" shaft, also with a base mount.

The "base speed" of a 1.5 HP dc motor is likely to be something like 1200 rpm, so to get 2500 rpm, you're going to have to employ field regulation (AKA, field weakening).

An 180 volt armature probably means a 90 volt series field.

KB Electronics sells many drives which could easily do the job.

However, KB doesn't offer a field weakening drive.

If I were to do it, I would definitely go the VFD route. On a drill press a VFD has to be the best way to go. Not so sure on a mill.

I have a VFD on one of my mills (CNC) which also has a reeves variable ratio pulley drive. I may take the VFD off it and put it on the other mill which has a step pulley drive. I find myself using the reeves drives to change speed rather than the VFD because the CNC mill tends to push cutters harder than the manual mill. If you try to run at a low speed with the VFD the hp available to the cutter is seriously reduced and can result in broken cutters, even broken brand new $15.00 US made 2 flute 3/8" TiN coated Co HSS end mills (ask me how I know). The reeves drive allows reduced speed with the full 3hp available to the cutter (less drive efficiency of course). The other reason is that the reeves drive likes to have its ratio changed from time to time or it starts to make noises.

The only reason I haven't taken the VFD off to put it on the other mill is a lack of time to do it.

Fitch

I'm not sure I understand your line of thought here, Fitch. A DCPM motor can deliver rated torque at any speed, and a series-wound DC motor delivers greater torque at high loads. Speed may droop but the cutter keeps turning and cutting.

Perhaps you break bits on the mill because the cutter stalls while the table keeps moving -- SNAP!

Induction motors, VFD or not, will stall when torque limit is exceeded and speed drops significantly due to load. DCPM motors maintain torque per amp at any speed, series wound motors develop more torque as speed droops clear down to zero speed.

I think a speed-controlled (limited) series-wound motor (as a treadmill motor) would be ideal for a drillpress. The speed control would limit max speed to keep from burning drills with excess speed, but the motor could grunt fit to break clamps and challenge the rigidity of the column (for short durations that don't result in overheating) to keep that cutter turning.

I have a GE DC motor that I bought from surplus center that is a close match. Its 1.25 HP at 25?? RPM but it is a 105 volt motor. I use it with a 90V speed controller and it works just fine. Last time I looked surpluse center still sold this motor.

chuck

I have a 1.5 HP, 180 Volt DC motor for sale. Email me at paulhagenATinsightbbDOTcom if you want it. Paul