Another Bridgeport retrofit Series II need stepper motor specs.
I am in the middle of a retrofit on a Bridgeport I picked up.
I am using copley controls drives which are programmable.
I need the rotor inertia,rated current,rated torque to enter into the software.
I can measure the inductance,and the resistance.
The motors have six wires brought out to the control cabinet.
I have not Identified whether they are sigma or superior yet.
The original voltage was the typical 56 ish volts,and they were operated unipolar.
It also used the saturable reactor current control on the drives. I have removed all that.
The present setup will be 72 volt dc power supply.
Copley controls stepnet drives 7A max.
Original step motors.
Masso CNC Controller.
Solid state Fugi contactors for spindle motor fwd/rev.
24 volt dc control power supply.
I had planed to wire the motors in half winding config,but the math says my 72 volts is too high.
I may need to use full winding config,since I have 72v and my drives only do 7A peak.
Anybody have any info about that rotor inertia? and rated torque?
Re: Another Bridgeport retrofit Series II need stepper motor specs.
I found this post today on the pm forum John Stevenson says the motors are superior M112. I pulled up a catalog and the m112 is a double stack. It is 7.67" long vs 5" for the m111 single stack motor. Not all of the electrical specs line up though. The inductance measurement of my motors is closer to the m111 single stack motor. But my motors measure 7.67" long. I need a superior electric catalog from 1979 I guess. Here are the links https://www.cnczone.com/vb/cnc-machi...26/index2.html ... https://www.kollmorgen.com/sites/def...Electric_0.pdf
Re: Another Bridgeport retrofit Series II need stepper motor specs.
Ok I have sorted this motor spec issue. There are a few guys on this forum,and other forums who have good info on these motors.
I read post's and searched documents all day yesterday. Some forum members disagree on certain specs of these motors.
What I found is that they are all correct. I'll explain, the motors can be wired in three different connections. Unipolar, Bipolar Series, and Bipolar parallel.
Current can be switched to the motor two different ways. One phase on, and Two phase on.
So you can have several different combinations and the specs differ among those combinations.
I found an older datasheet that has all this information on it and I'm going to try to post a picture of the relevant section.
The motor is Superior Electric M112-FJ-8012, double stack, nema 42, 8 wire connection, rotor inertia 0.114 oz-in-s squared.
If you have the sigma motor sorry I cant help you, I have a seriesII nc machine and this is the motor I have.
Bridgeport part number 025805 The motor is wired unipolar/series from the factory. Operated in unipolar on the Bridgeport.
Under the cover on back of motor you will find the 8 wire connections, 6 and 2 are jumpered, also 7 and 8 are jumpered
1 and 3 are taken out as one phase, and 4 and 5 are taken out as the other phase. The jumpered connections 6-2 and 7-8 are taken out for unipolar operation.
So for Series Bipolar operation you dont have to rewire the motor connections. You will ignore the center tap connections for unipolar, white/yellow wire,and white/blue wire both labelled 5
Each axis motor cable has two of them brought to the cabinet and they are labelled x5,x5, for x y5,y5 for y z5,z5 for z. You get the idea. Tape those up and set them aside.
The white#1,and white/red #3 are one phase of the motor, call it A. White/black #2, and white/green #4 are the other phase of the motor, call it B. Series Bipolar connected.
One thing that is confusing to me about the specs superior publishes is the inductance value is measured with both phases in series. So if you measure phase A white#1 to white/red #3 you get 10.5mH
The spec in the datasheet is 21mH if you measure phase A,and phase B in series you will get 21mH. I think this is strange,and now I have to check with my drive manufacturer to see which they want single phase or both.
If I cant get the picture to behave,I'll post a link to the pdf and you can pull it up.
You see there are 6 different holding torques for the different winding connections,and 1 phase on or two phase on.
Last edited by Deese; 09-14-2018 at 11:45 AM.
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Another Bridgeport retrofit Series II need stepper motor specs.
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