Dear Madam/Sir, I have a M091-FD-308 stepping motor from Superior Electric: (See attached picture) and I have a bipolar driver. Is the M091-FD-308 stepping motor bipolar? so that I can use my bipolar driver (LIN R256)?

Thank you, Rachid

 

It looks like it is a pretty standard 200 step motor with split windings. Here's the wiring diagram using standard colours, but check with multimeter.

 

Dear Madam/Sir, I have a M091-FD-308 stepping motor from Superior Electric: (See attached picture) and I have a bipolar driver. Is the M091-FD-308 stepping motor bipolar? so that I can use my bipolar driver (LIN R256)?

Thank you, Rachid

Dear Irving, First of all thank you for your fast reply.
Yes I already wired the motor-driver system which was also ready with an old bipolar motor, so I need just to replace the old motor with the new motor. I asked this question because I contacted the LIN company asking them if I can use their R256 driver for the M091-FD-308 stepping motor from Superior Electric and they said I should be sure first if the M091-FD-308 stepping motor is a bipolar motor (can be wired as bipolar) because the LIN R256 driver is bipolar. Also is good to use the LIN R256 because all the software I wrote and used for the old motor is ready so to avoid writing again the code if I use a new driver.

Thank you, rachid

 

Dear Ivine, I forgot to say: So I can go ahead an use the LIN R256 driver(bipolar) with the M091-FD-308 stepping motor from Superior Electric, as the M091-FD-308 can be used as bipolar?
The Superior Electric company is not responding ......

Than you, rachid

 

Yes, it should work OK with that driver.

The phase inductance of that motor is 28.5mH and phase resistance is 6.8ohm. You may need that info to tune the driver. Its not a fast motor, <200rpm probably. It will run faster wired like this, but with less torque.

The Superior Electric company is not responding ......

Not surprising, they stopped making stepper motors a few years ago, and sold the business to Danaher Motion. That drive is old technology and hasn't been manufactured for years, plus it was a customer special so unlikely you'll get any further info on it.

 

That is a unipolar motor, bi-polar have just two windings.
I have some old Slo-Syn catalogues I can check.

 

That is a unipolar motor, bi-polar have just two windings.
I have some old Slo-Syn catalogues I can check.

True, It is a split winding (6 wire) unipolar, but it can be driven bipolar as well. Bipolar motors can have 4 or 8 wires with either 2 or 4 discrete windings.

These motors are very common in the hobby cnc maker community.

 

That is a unipolar motor, bi-polar have just two windings.
I have some old Slo-Syn catalogues I can check.

Yes there are links talking about Slo-Syn driver installation/wiring like in: https://www.bibus.hu/fileadmin/edit...periorelectric_series_ss2000md4_manual_en.pdf
about "INSTALLATION/INSTRUCTIONS for SLO-SYN MODEL SS2000MD4 TRANSLATOR/DRIVE"
There at page 4 they say: "The SLO-SYN SS2000MD4 Translator/Drive is a bipolar, adjustable speed,two-phase PWM drive which uses hybrid power devices."

Also at page 13 there is a table "MOTORS FOR USE WITH THE SS2000MD4 TRANSLATOR/DRIVE" where M091 motors (I think all of them as they mentioned only M091) are listed to be used with SS2000MD4 driver (that driver is mentioned at page 4 as a bipolar driver).

> That is a unipolar motor, bi-polar have just two windings.

yes, as I read, in principle 6 lead motors are unipolar by default if the central tap wires are used (for example shorted) so the two windings (for each phase) are split in two halves and for that reason bipolar motors have more torque because they use the entire winding. If the tap central wires are not connected the motor is used as bipolar. The bipolar electronics is more complicated using an H bridge to reverse currents between sequences while in unipolar motors the current always flows in one direction so simple electronics. You can watch the youtube video:

where they explained, in practice!, how a 6 lead motor can be wired/used in unipolar or bipolar modes.

 

Yes, I have built a Bi-polar drive some time ago and there is definitely more to it than the uni-polar.
Now there is cheap versions on ebay etc.

 

Yes, I have built a Bi-polar drive some time ago and there is definitely more to it than the uni-polar.
Now there is cheap versions on ebay etc.

Thank you, would you like please send me the name and part number of your bipolar driver. Is your driver is also a controller with protocol commands like trough RS232?

I should use the LIN R256 driver because I am used with its protocol commands: I am really in hurry to write the data acquisition program that uses this motor.

One last question: I attach here the installation instructions manual of the LIN R256 driver/controller and at page 10 there is the chematic of using the driver with a RS232-485 converter card (that I already tested and used). My question is about the Power Supply and the current that the superior Electric motor drive (here below its specifications):



you see for 5.8V it drives 0.85A, so for 12V (as my driver needs an input voltage of 12V to 40V) it will drive more current. This current is at the Ampere level so does it need thick wires but you see at page 10 in the attached file within the driver system we use DB connectors with thin wires. I am a physicist (and i really appreciate this forum with the interesting conversation I already had with you) so I concentrated only on the programing level, so I ask you if the driver system (page 10 of the attached file) can sustain such high currents?

Thank you, Rachid

 

If you read further in the manual it gives an example, on page 13 of the commands to set the phase current for your motor. The total phase current for your motor/driver is 2.8A peak (not continuous). The driver is rated for 2A a phase (4A max) but its actually much less than that on average and DB connector pins are rated at 5A so there isn't a problem. The power wires to pins 1 and 6 from the power supply should be 20AWG stranded (16/0.2mm, 0.5mm sq).

The driver will control the phase current to prevent the motor overheating. You can use any supply voltage from 12 to 40v with the R256. Higher voltages will allow faster motor speeds but it should work OK with 12v.

 

It was just a simple drive I built. See the L298 & LMD18200 , there are board mounted ones on ebay.
With any stepper, it should be ran at exactly the rated plate current, the problem is that as rpm increases, so does inductive reactance, reducing the current, in order to overcome this, modern drives use a much higher voltage rating for the motor and control the correct constant current throughout the RPM range using PWM etc.

 

My small milling machine had 3 x NEMA34 motors originally driven by 3 home-built drivers using L298 chips and a 24v supply. They worked, thats about the best I can say - it was still better than trying to operate it manually. Eventually, when funds allowed, they were replaced by commercially available drivers and a 60v supply which increased motor speed from 120rpm max to around 500rpm as well as getting some serious torque at that speed. That made it more useful as a CNC machine as jobs could be left to run themselves with a reasonable chance finshing and not stalling in the middle of a cut!