View Full Version : about motors
The SB (see Yike)is within 2 ft. of it's final location.
It has a westinghouse 1hp 208v 3 phase motor.
There's no 3 phase in the house. I'm pretty up on the phase conversion methods, but why not change the motor? There are several 1-1 1/2 hp motors and even ones with more power that will run from a nearby 220v single phase outlet. Many are not very expensive.
Should I be talked out of a motor change?
Robert Jones
05-05-2001, 08:48 AM
Ken, I recentlywas confronted with this problem, too. For approximately $220 you can get a vfd from automationdirect, and if all the wiring on your machine is good, can be up and running in no time. This gives variable speed, reversing, smooth operation, etc. I did not know about automationdirect at the time, so I went with a 1 1/2 hp, 220v 1ph motor. I had to replace all the wiring on my lathe as it was rotted.Look carefully at the condition of the electrical system on your lathe. I am happy with the set up I have, and am in the process of changing to the link type belt which is supposed to help with smoothing out the operation of the lathe and make better finishes. I really have not experienced any problems with finishes, but I do need new belts, and the link belt permits changinging without removing the spindle. A good single phase motor will run about $200, new overloads to protect it will be about $25, and then you will have to remove, install, rewire, etc, which all takes time. While you are doing this you can look at the condition of the pulleys, countershafts, bearings, and decide if they need attention. All of these things will need to be done eventually, so I guess it comes down to how long do you want to wait to make chips, your experienc at doing this type of thing, and what's available to you now. I think with 220v available at a wall outlet,I would get the machine ready to run, and plug in a vfd. Bobby
Robert!
I'm in your debt! I had looked at inverters as a solution but had rejected the idea because all of those that I found were extraordinarily expensive for this purpose. So I'd resigned myself to conversion before I saw the motor installation and knew how easy it would be to change.
I just ordered a vfd with specs to do this job, and it is as you said, only $219. It looks suspiciously like one of the ones listed in my Grainger's catalog for some 3 1/2 times the money.
So thank you for being in here at just the right time!
[This message has been edited by KenS (edited 05-05-2001).]
Robert Jones
05-06-2001, 08:37 AM
Ken, you are welcome. I hope it works out well for you. If I had it to do over, I would certainly go with the vfd, and I'm considering doing it now even though mine is working great. I like the idea of virtually instant speed changes. Bobby
I agree -- the "surplus" VFDs are the way to go for 3-phase conversion. They're great.
If you have a 208V motor though, you'll probably need a new motor anyway, as I assume the VFD puts out 230V 3-phase. (Or it may be a settable parameter in the VFD, but whatever the situation is, make sure you match the motor and VFD voltages.)
The vfd devices referenced by Robert are new Hitachi solid state programmable boxes. As I said they appear quite similar to ones sold in Grainger's under their 'Dayton' name, but are cheaper by far, even cheaper than the jobber rate I can get by half.
Automationdirect.com is worth looking at. I hadn't been aware of them, but when I went there and looked around I could see that they are offering solutions for hobbyists even while supplying industrial state of the art needs.
For what it's worth, I've also found these places:
http://www.vfds.com/vfdprice.htm
http://www.dealerselectric.com/
I bought mine from the top one, friends have dealt with the bottom one.