3 phase lathe motor. Sizing/wiring VFD?

[HoosierBuddy]

Hey guys,

Over the weekend, I bought a South Bend Lathe. It's equipped with a 3-phase motor. The tag is shown below.

It reads:

GENERAL ELECTRIC
HP 3/4
RPM 1725 1425
V 208-220/440
MOD 5K43MG3
CY 60 50
CODE K
? 1.25
PH 3
A 2.6/1.3
TEMP RISE 40/50C
FRAME 56
TIME RATING CONT.
SER NO. YJL
Fort Wayne, Indiana Made in USA

So....I have this set up in my garage. I don't have 3-phase power. I've decided I want to purchase a VFD and use it to convert single phase to 3-phase and give me speed and direction control on the motor. But I'm wondering about a couple of things:

1. Why does the tag indicate 220 and 440? Is that something that can be switched in the motor?
2. If so, how?
3. If I purchase a 1 HP VFD that requires 220-240 single phase input, can I run that from my nearby lift circuit? It's a 220 V Receptical on a 30 AMP breaker by itself. My thought is, I would unplug the 2HP lift motor and plug in the VFD via cord that would run over to the lathe...at least initially to be able to try this thing out.

Eventually, I'd like to run wiring directly to the lathe...but it's going to require a bunch of work to get it in the wall...or I've got to come to terms with putting it in conduit, which I really don't want to do.

BONUS QUESTION:

How old do you think this motor is? Any chance it is original to a lathe made in 1953?

THANKS GUYS!

Phil

 

[930dreamer]

208-220 is the low voltage, 440 high voltage. Motor/wiring box should have a diagram for low/high voltage wiring.

 

[BillK]

Phil,
I am not real familiar with Variable Frequency Drives. Will it convert your single phase to 3 phase for the motor ? You might want to put a post on the Home Machinist forum. Lots of knowledgeable guys over there.

http://bbs.homeshopmachinist.net/index.php

 

[930dreamer]

http://www.practicalmachinist.com/vb/transformers-phase-converters-vfd/

Here's another good site.

 

[Norcal]

Here are some links.

http://www.driveswarehouse.com/Drives/AC+Drives/Micro+VFD/L100-007MFU.html

120 volt input 240V 3Ø output for a 1 hp motor.


More:

http://dealerselectric.com/item.asp?cID=28&PID=428

 

[katit]

TECO VFD is what I have on my 9x20
http://www.factorymation.com/s.nl/it.A/id.193/.f

Converts 110V to 220 3 phase. Works excellent and you may want to put control panel on your lathe. I can send you PDF - PM me with your email address.

You kill 2 birds with one stone - get your lathe running on 110 and getting variable speed which is essential IMO. Especially after you tried once

As far as I remember - some old motors do not work well with VFD though..

Congrats on that lathe! I've been waiting for one and ended up buying "like new" chinease cheap.

 

[Torque1st]

You will need to rewire your lathe controls. The VFD must be connected directly to the motor without going thru any switches etc.

 

[HoosierBuddy]

TECO VFD is what I have on my 9x20
http://www.factorymation.com/s.nl/it.A/id.193/.f

Converts 110V to 220 3 phase. Works excellent and you may want to put control panel on your lathe. I can send you PDF - PM me with your email address.

You kill 2 birds with one stone - get your lathe running on 110 and getting variable speed which is essential IMO. Especially after you tried once

As far as I remember - some old motors do not work well with VFD though..

Congrats on that lathe! I've been waiting for one and ended up buying "like new" chinease cheap.

That would be awesome!

I'll send you a PM.

I've been looking for a lathe literally for YEARS for the right price. One day...BOOM....this lathe shows up on Craigslist and it is an hour away, but I'm in that county all the time, so it wasn't even really out of my way.

Some of those Chinese machines are darn good according to everything I've read. I think Grizzly is unveiling their new lineup of retro South Bend 9s and Heavy 10s in the next few weeks. They are having them made in Tiawan IIRC. If all goes according to plan...you'd be able to buy brand new lathe identical (right down to the South Bend tag, because Grizzly owns the rights) to mine in the next few months.

Phil

 

[tdkkart]

So....I have this set up in my garage. I don't have 3-phase power. I've decided I want to purchase a VFD and use it to convert single phase to 3-phase and give me speed and direction control on the motor.

Congrats on the lathe purchase, nothing handier than a good lathe.
One thing I will warn you about, if your lathe has a threaded spindle with screw-on chucks I would advise against running it in reverse for a couple reasons.
#1 there are very few applications where you will need reverse.
#2 if you do not happen to have the chuck sufficiently tight, when you turn on the lathe the chuck may unscrew itself from the spindle and not only drop on the lathe bed, but may also fly off the lateh altogether and do serious damage to not only you but your shop.

That said, VFD's are wonderful pieces of equipment, I have one on both my lateh and mill, greatly expands the versatility of the machines.

 

[elett]

?= SF 1.25 (service factor)

 

[HoosierBuddy]

Thanks for all the info guys!

I ordered the TECO 1 HP 110 V to 220V 3-phase VFD linked above.

I have Katit's plans for building a motor controller for a small lathe. Although the plans were originally for use with a small import lathe, they should be EVEN EASIER to use on my old South Bend. Half the instructions are for how to procure a 3-phase motor for your chinese lathe...and I already have one of those on my old iron...so, I got that going for me.

Anyway...those plans are cool because they have you building a control box with a reostat speed control, jog button, etc....which really should make the lathe more useful. It's probably not AS manditory on a backgeared lathe, like mine...but still...very nice concept!

Thanks again guys.

Phil