Need Help!- SEM MT30H4-2.5 motors

[EMMKAY]

The servos are SEM MT30H4-2.5 rated with Cont Stall torque of 2.1NM TENV Max RPM 2500 V110 and Pulse amps 25. I couldn't get any data on the motors. Can I use the servos with a servo drive by not using the tacho and uprading the encoder to something like 2000 cpr.

I would like to use the motors as I have about 9 of them on hand! So if someone could guide me to soem technical data about the motors..

Any input is greatly appreciated

Cheers

EmmKay

[Sparky_NY]

Originally Posted by EMMKAY The servos are SEM MT30H4-2.5 rated with Cont Stall torque of 2.1NM TENV Max RPM 2500 V110 and Pulse amps 25. I couldn't get any data on the motors. Can I use the servos with a servo drive by not using the tacho and uprading the encoder to something like 2000 cpr. I would like to use the motors as I have about 9 of them on hand! So if someone could guide me to soem technical data about the motors.. Any input is greatly appreciated Cheers EmmKay

Of course it depends on the particular drive you plan on connecting to and its features but I just did a retrofit using powertron servos which are nearly identical to your sem's. I removed the tach brushes to disable the tachs and replaced the encoders. Bridgeport used both powertron and SEM motors on their machines over the years.

Have a look at my retrofit thread, there are pictures of my motors, the encoders etc. and I think you will find they are nearly identical to your SEM motors.

http://cnczone.com/forums/showthread.php?t=93483

Hope this helps some.

[gridley51]

SEM have a website.From that website you can dowmload the motor data.It`s not difficult to find.

[EMMKAY]

@sparky. Thanks for your input.. I am reading your thread. The motors are slightly different as I think the braking wires are not there.... But I have emailed CNCdrive for the cost and shipping charges for three controllers to my location. The motors do have ROD450B rotary encoders on them that seem to be in full working order apart from the mounting holes that need repair.

@gridley51.. did check the SEM website.. but I guess due to being a pre 81 motor it doesn't appear on the website or for that matter I haven't had much success in find that particular variant of MT30H4 range.. the model of the motor being MT30H4-2.5 with specs mentioned in the first post at top.

If I was to replace these motors with steppers what kind of torque I would be looking at for the steppers.. Currently I have 1200oz-in 8 wire steppers that I might use. I do have three stepper drivers at hand at the moment but I am struggling between making the decision of reusing the old motors and completely replacing it with the new stepper set up (which obviously has lower power requirements)..

As always suggestions from the experienced are valued highly!..

cheers

Emmkay


The machine is a bridgeport series 1 MDI with TNC131.. the control cabinet being completely trashed...

[Sparky_NY]

Cncdrives gives free shipping if you buy 4 drives, might be something to consider, it makes that 4th drive very inexpensive. You are correct, my motors do not have a brake.

What about a email to the SEM motor website, perhaps they can supply you with the data for your older motor.

As for replacing with steppers, its hard to say because we do not know the specs of the servo motors or what the machine application is.

Originally Posted by EMMKAY @sparky. Thanks for your input.. I am reading your thread. The motors are slightly different as I think the braking wires are not there.... But I have emailed CNCdrive for the cost and shipping charges for three controllers to my location. The motors do have ROD450B rotary encoders on them that seem to be in full working order apart from the mounting holes that need repair. @gridley51.. did check the SEM website.. but I guess due to being a pre 81 motor it doesn't appear on the website or for that matter I haven't had much success in find that particular variant of MT30H4 range.. the model of the motor being MT30H4-2.5 with specs mentioned in the first post at top. If I was to replace these motors with steppers what kind of torque I would be looking at for the steppers.. Currently I have 1200oz-in 8 wire steppers that I might use. I do have three stepper drivers at hand at the moment but I am struggling between making the decision of reusing the old motors and completely replacing it with the new stepper set up (which obviously has lower power requirements).. As always suggestions from the experienced are valued highly!.. cheers Emmkay The machine is a bridgeport series 1 MDI with TNC131.. the control cabinet being completely trashed...

[EMMKAY]

Just heard from SEM.. this is what they have to say.. so I am still looking

"I’m afraid but we cannot provide any further details as sent in my previous email. This is a very old motor and we no longer have record of this motors specification/data.
We advise you to contact the seller of this motor."

The only thing I have to go by is what is on the tag plate of the motors..
Type MT30H4-2.5
Serial No K76121
CONT STALL TORQUE 2.1 NM
MAX RPM 2500 - VOLTS 110 PULSE AMPS 25

Can anyone give me an idea about stepper replacement based on the info above..! again the machine is Bridgeport Series 1 MDI with TN131 controls(trashed!!!)

cheers