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Re: JMC integrated Servo - which Drive Type?

Posted: Tue Jan 11, 2022 3:06 pm
by Centroid_Tech2
The DB25 at 5VDC is used for faster signal turn off since the Step and Direction inputs seem setup for a wide voltage range (5~24). The "Enable" signal functions as a disable and is drawn as optional.The alarm output is driving an opto-coupler on the relay board which requires 0.35mA at 5V and needs no addition resistors added.

Re: JMC integrated Servo - which Drive Type?

Posted: Tue Jan 11, 2022 3:47 pm
by suntravel
Do I have to splice the ribbonwire to connect to the relay board as drawn?

Regards

Uwe

Re: JMC integrated Servo - which Drive Type?

Posted: Tue Jan 11, 2022 5:31 pm
by Centroid_Tech2
Yes, If you use the 8 relay board from Centroid which is what is drawn there. You can use whatever relay board you want as long as the current draw is
low enough. This one should work fine also:

Re: JMC integrated Servo - which Drive Type?

Posted: Wed May 17, 2023 11:18 am
by CNCMaryland
Bringing this thread back to life as I just finished up my bench testing of these integrated servos.

I wanted to ask a few questions here.
1) Pulse Rate - I am currently set to 6400 pulses. I can go up to 8000 with these motors. Wanted to get a recommendation on this
2) Step Frequency - Currently set to 200khz. Wanted to get a recommendation on this as well.

I have followed the JMC Draft Schematic that was linked in this thread.

Re: JMC integrated Servo - which Drive Type?

Posted: Wed May 17, 2023 4:19 pm
by CNCMaryland
CNCMaryland wrote: Wed May 17, 2023 11:18 am Bringing this thread back to life as I just finished up my bench testing of these integrated servos.

I wanted to ask a few questions here.
1) Pulse Rate - I am currently set to 6400 pulses. I can go up to 8000 with these motors. Wanted to get a recommendation on this
2) Step Frequency - Currently set to 200khz. Wanted to get a recommendation on this as well.

I have followed the JMC Draft Schematic that was linked in this thread.
Doing some reading on this in the meantime. Based on the calculations with 6400 pulses and 200khz and a 5mm leadscrew I should be able to achieve 375ipm/9,525mm/min.

I assume the tradeoff is increasing the pulse rate to 8000 will lower my max speed to 300ipm/7620mm/min.

I assume the 8000 provides increases accuracy. Any other negatives to going with 8000?

Re: JMC integrated Servo - which Drive Type?

Posted: Wed May 17, 2023 4:43 pm
by cnckeith
8000 should be good with this servo.
going this high with steppers would see a drop in torque

Re: JMC integrated Servo - which Drive Type?

Posted: Thu May 18, 2023 9:09 am
by CNCMaryland
cnckeith wrote: Wed May 17, 2023 4:43 pm 8000 should be good with this servo.
going this high with steppers would see a drop in torque
Thank you Keith. I did some reading in the Knowledge Center and was able to get an understanding of the calculations to determine max speed, etc.

Going with 8000 pulse, and 200khz. That will allow me with a 5mm ballscrew to max at 7500mm/min, which is way more than needed due to the small size of the machine.

I'll have to make a build thread soon!