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View Full Version : Servio motor Delta adas b2 Software and electronic gear ratio



jhonansaro
02-03-2018, 06:17 PM
Hi there

what is exactly the meaning of electronic gear ratio in Delta asda b2 Servo Driver?

and how to calculate it?

regards
jhonansaro

m_c
02-03-2018, 09:37 PM
It's gear ratio between the motor encoder, and the drives encoder output/step input.

For example, a typical modern servo has a 10'000CPR (counts per revolution) encoder.
With no gear ratio, the encoder output from the drive will be a direct copy of the motor encoder (I.e. 10'000CPR)
By changing the electronic gear ratio, instead of getting a 10'000CPR, you can increase or decrease that count by the ratio you input. I.e if you change it to 10:1, you'll only get a 1'000CPR encoder output.

If the drive accepts step/dir, or CW/CCW input, the same applies to the input signal.
Instead of needing 10'000 steps to move a single turn, if you apply a 1:10 ratio, you only need 1'000 steps to move a single turn.

JAZZCNC
03-03-2018, 12:09 PM
The main used reason to use EGR is if your controller is pulse limited it allows you to get full rpm from your motor. So let's say using 10,000CPR encoders and motor rated RPM is 3000. You'll need 10,000 * 3000 / 60=500,000 PPS or 500Khz frequency from controller.

So if your controller can only provide 100Khz then your RPM will be limited to 600rpm. In which case you'd use 1:5 ratio to give 1 pulse in 5 out.
The cost of this is your encoder count is effectively reduced from 10,000CPR to 2000CPR which affects smoothness and resolution.

jhonansaro
16-03-2018, 08:09 PM
Hi there

thanks for the reply

my setting currently for my servo are as follow, and I should say that I am getting a smooth run so far, but off course i have not install them completely yet;

P1-44 = 480
P1-45 = 16
P1-36 = 5 ms
P1-52 = 100
P2-08 = 36

Could you please verify all these for me
Finally pulse per unit in mach3 is set at 571
if you have any recommendation for modifying any parameters in regards that I can get a better performance please let me know

My Pinion circumference is at 175 mm
I have 10:1 gearBox
The speed that I look for is at least about 12000 mm/min


regards
jhonansaro