What is max current for my steppermotor?

[sierra]

Hi,

I´m totally newbie on the forum, and totally newbie with cnc macines.

But i have build stepper controller witch i found on pminmo´s page
Controller was designed by Tachus42.

System is running but i´m not sure about voltage and current.

My motors are astrosyn 23LM-c325-21 24V unipolar motors.
So the voltage 24V is ok, but does it matter how much current i give the motors?

i measured resistance of wiring i find out that resistans is from end to end 148ohm´s so the resistans of one coil is 74 ohm´s

then the motor Amp´s is 0.324 Amp´s calculated from values of voltage, resistanse (24/74=0.324 Amp´s) is that right?

What happens if i use power supply of 24V1.4 Amp´s ?

Or coud i use 24V 8amps? is it possible to destroy my motors ? with 24V8A

Thanks any answer

Best Regard´s

Jarkko From Finland

[pminmo]

What values are on the nameplate? How many wires? I can only find partial info on that series of motors. Most of which would lead me to beilieve the motor is in the 1 to 1.5A range, although your coil measurement doesn't seem to correlate at 148 ohms, the data I found says from roughly 2 ohms to 8 ohms. http://www.eminebea.com/content/html...ist/pdf/23lm_c.

[sierra]

Hi,

And thanks for fast reply.

Name plate says. Astrosyn stepper
type 23LM-C325-21V
no T6130 minebea co LTD
It has 6 wires and it has 4 coils. i measure 74ohm´s from middle of 3 wires to the most left it gives 74ohm´s and same to right. If i measure most right and most left of those 3 wires witch has contact to each other i have value 2X74ohm´s =148 ohm´s.
I even try with 180ohm´s resistor, so the values are correct.

I have try to find some data to those motors but no find´s
the one i try was running ok whit Mascot power supply 24v max 500mA

But motor seem´s to come quite hot like 60-70 degr celsius (140 to 160 fahrenheit) after 5min to use is this normal?

What you suggest to the amp´s what i coud run thru motor?

Can i destroy those motor whit to give too big current? like 3amps
My board only can take like 5 amps

Best regards

Jarkko From finland

[pminmo]

Yes you can damage the motor with too much current. Steppers run hot, but I'm not sure about 160F. With that much coil resistance I would expect a current in the range of your power supply, not higher. Sorry I can't be of more help.

[sierra]

Thanks anyway Pminmo.

i willl try to use that 0.324A that i calculate. if it seems to be to low i will buy i bigger supply.

Or i use some current resistors between the supply and motor.

I will post how my project progress.

Best regards

Jarkko

[sierra]

Ok,

Has been made some testing and one power supply is out of day´s dont know why ?

I used 24V powersupply max rated 500mA i connect it straight to tachus42´s 3 axis board i made some testing and suddenly everything was stopped. i opened the supply and there was regulator LM315T inside i guess that it did burst.

Power supply was quite hot, but motors temp was ok. i disconnect supply and tested it whit electronic voltage meter it was dead.

Is there any chance to calculate what is correct current of those motor´s? fact of those motors you find top of this thread.

What sort of power supply i shoud build?
Now i have 24v 1.4A supply waiting but i´m scared to connect it if i destroy my 3 axis board or motor´s.

Can some one help me on this ?

Best regards

Jarkko From finland