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I installed a CMC PM Field Servo motor with gearbox on my milling machine knee. I needed it to work with a automatic tool changer to give clearance for long reamers and drills. I am not sure if a PM Field Servo requires a special kind of amplifier? My other amps are AMC Brush Type PWM Servo Amplifier, 25A20. Will this type of amp work or do I need another type?
unless you are mixing your terms, yes, your amc is fine.
I assume you mean PM servo motor (word field in there is redundant). If on the other hand you mean a field WOUND motor then PM is wrong to use. you know PM means permanent magnets right? so either you have a motor with magnets in it or you have a motor without magnets but field coils in their place instead. If that is the case, then no the amc will not work; we sell field wound motor drives - email me and I will send you links to some options or just google 'field wound motor drive.'
If the motor is wound field, you could supply it off of the power supply that supplies the 25A20, you would need to know the voltage requirements for the field, the other option is to build a separate DC supply, usually the current demands are not that much.
Al.
These Cleveland Motion Control DC Servo "PM Field" motors are not easy to find data on. I did find out these type servo motors only spin at 2,000 rpm or less and if my memory is correct permanent magnets on the rotor and field winding on the outside. Also they are not good for large motors due to heat and not used that much. This motor I have has a tach and encoder.
What I need to find out is what do I buy to feed my emc2 analog control signal 10v +- to and get my 140vdc or lower voltage if I need it from my power supply to my 2 motor leads? A amplifier is what it is called for my other non-pm field motors. The PM Field issue is making buying a drive or amp impossible until I know what will work. Hopefully I can find out with the data below. I'm over my head on this problem.
My motor data is:
37 ft/lbs continuous torque
Kt= 10.7 lb-in/amp
kv= 126.7
sorry, that info does not help.
BTW, if PM mags on rotor and coils in stator, that is called a BRUSHLESS AC OR DC motor and has 3 wires not 2 coming out. i suspect you really have a regular ol dc PM servo motor.... want to give us the part no? I for one have lots of old CMC info and will share....
BUT there are 4 good ways to know what you have - report back!!
1) give us the motor part no
2) give us a pix of it and its nameplate
3) exactly how many wires come out and what size? (field wound needs more than 2 wires total)
4) if indeed you have only 2 wires coming out, tie them together and rotate the shaft: is it hard to turn? then you have normal (probably so) DC PM servo motor....
I personally have not seen a CMC motor with a wound field, but it is not hard to make a power supply, the higher the voltage and hence current will set the limit for RPM and torque, for e.g. on DC spindles with wound field it is common to decrease the field voltage for higher rpm at the expense of torque when needed.Quote:
Originally Posted by greeder88
If this motor has a tach, which is not commonly used now, it is an older DC brushed motor.
I have most of the CMC motor data sheets, so if you supply a number I may be able to give you the info.
You may even be able to use rectified 120v for a suitable supply.
As Mike mentioned, I think you are getting your terms mixed up, if it IS a PM motor then you are ahead of the game as far as drives are concerned.
Al.