Author Topic: Change Stepper to Servo  (Read 2376 times)

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Offline boskap

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Change Stepper to Servo
« on: October 26, 2017, 04:52:12 PM »
Hi
Is it Possible to change my StepperMotors  to this Servo with integrated Driver
http://www.jmc-motor.com/products.php?cid=249&id=162

How i must them Connect to the Pokeys57cnc ?
Settings ?

thx Peter

Offline joeaverage

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Re: Change Stepper to Servo
« Reply #1 on: October 26, 2017, 06:04:02 PM »
Hi,
yes its possible to run these motors.

While they are advertised as servos I suspect they are in fact stepper motors with encoder feedback, good
to be sure, but still have the same essential limitations of a stepper, poor torque at high speed.

I would insist that I were provided torque/speed diagram before I parted with any money. Don't be taken in
by advertising hype.

Craig
My wife left with my best friend...
     and I miss him!

Offline boskap

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Re: Change Stepper to Servo
« Reply #2 on: October 26, 2017, 06:47:44 PM »

over posteps ?
or posteps are didnt needed because this servos have the driver implemented

but how i connect them direct to pokeys57cnc

Offline joeaverage

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Re: Change Stepper to Servo
« Reply #3 on: October 26, 2017, 07:29:34 PM »
Hi,
you can connect them just like you would an open loop stepper, Step, Dir and Enable.
You can also monitor the fault output signal from the servo/driver if you wish.

Craig
My wife left with my best friend...
     and I miss him!

Offline boskap

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Re: Change Stepper to Servo
« Reply #4 on: October 27, 2017, 01:40:07 AM »
sorry i dont not know howbto vonnevt it directly to the pokexs device
whivh pins from the 8pin vonnector

sometimes i read i need then poblocks
or not

can you make a short wiring diagramm

thx

Offline joeaverage

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Re: Change Stepper to Servo
« Reply #5 on: October 27, 2017, 01:46:25 AM »
Hi,
how have you connected your stepper drivers? These servos should connect the same way.

Craig
My wife left with my best friend...
     and I miss him!

Offline boskap

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Re: Change Stepper to Servo
« Reply #6 on: October 27, 2017, 01:53:23 AM »
hmmm
my steppers are conmected ofer the posteps driver
but need i the postebs driver when the servo have there own

Offline joeaverage

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Re: Change Stepper to Servo
« Reply #7 on: October 27, 2017, 02:25:11 AM »
Hi,
page 16 of the 57CNC manual shows the pinout of the 8 pin motor sockets.

You will need the Enable pin1, Dir pin3, Step pin5 and if you want the servo to be able to signal an error back to Mach then Error pin7.
Pins 1,3,5 are all DO5 type pins, 5V output, 100Ohm impedance, 8mA max current per page 19 of the manual. Should be able to drive the input opto couplers
directly. The Error input is DI5P type, 5V tolerant, pulled high by 10kOhm, page 19, and can be connected to the Alm+ output of the servo driver.

The connection is simple.

Do you really want those servos? Get a torque vs speed diagram before you buy them. If they can't supply one then stay away from that brand.

Craig
My wife left with my best friend...
     and I miss him!

Offline boskap

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Re: Change Stepper to Servo
« Reply #8 on: October 27, 2017, 04:40:16 AM »
well now i have open loop steppers
and when i see what closed loop cost and this servo cost then my option ist servo
a friend from germany already hat it and is super happy with them

Offline joeaverage

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Re: Change Stepper to Servo
« Reply #9 on: October 27, 2017, 04:49:39 AM »
Hi,
then get a torque vs speed diagram for it. If they're good that is the evidence, they could be recommended by God himself but I still want to see the torque vs
speed diagram BEFORE I spend anything!

Craig
My wife left with my best friend...
     and I miss him!