Relationship between of Number of command input pulse and pulse train in positon control of Mitsubishi servo.

[vanquangtk]

Hello all, 

I don't understand therelationship between of Number of command input pulse and  pulse train in positon control mode of Mitsubishi servo.

May anyone explain for me.

[glavanov]

Number of command input pulses is how many pulses are needed for the servo motor shaft to make one revolution.

This is usually set by parameter in the servo amplifier .

With Mitsubishi servos for example MR-J4/JE series it's parameter PA05 - Number of command input pulses per revolution (default 10000).

So let's say for Fx3 PLC series [DRVI k10000 k10000 Y0 Y4] - this will command your servo (Axis-1) to make 1 full revolution within 1 second.

[vanquangtk]

10 hours ago, glavanov said:

Number of command input pulses is how many pulses are needed for the servo motor shaft to make one revolution.

So, number of command input pulses does not affect to speed, does it? Do you know what affect to speed of servo in position control mode. I read the manual, but it doesn't  mention about it.

Edited June 13, 2023 by vanquangtk

[glavanov]

Witch manual?

[vanquangtk]

21 hours ago, glavanov said:

Witch manual?

It is Servo Amplifier Instruction manual MR-J4-A

[panic mode]

number of pulses tells how far to move... rate at which pulses are sent controls the speed.

 

so maximum frequency of the PTO is one of limiting factors. small PLCs often have PTO that only get to few kHz, some may go to 100kHzor 200kH, dedicated modules for larger PLCs are definitely more capable (MHz). by parametrizing drive one can accomplish certain scaling so that for example axis can reach higher speed even when driven by slow PTO. but don't be fooled - this is a tradeoff... you may gain at one end (speed) but you loose at another (resolution). so one need to read the manual, do the math and set parameters correctly to get needed performance. but once you reach point where PTO cannot handle it, it is time to upgrade to more capable PLC.

[vanquangtk]

22 hours ago, panic mode said:

number of pulses tells how far to move... rate at which pulses are sent controls the speed.

 

so maximum frequency of the PTO is one of limiting factors. small PLCs often have PTO that only get to few kHz, some may go to 100kHzor 200kH, dedicated modules for larger PLCs are definitely more capable (MHz). by parametrizing drive one can accomplish certain scaling so that for example axis can reach higher speed even when driven by slow PTO. but don't be fooled - this is a tradeoff... you may gain at one end (speed) but you loose at another (resolution). so one need to read the manual, do the math and set parameters correctly to get needed performance. but once you reach point where PTO cannot handle it, it is time to upgrade to more capable PLC.

I still don't understand the role of the "number of pulses" parameter in position control mode. Why is it necessary when the distance varies depending on the position deviation?

In Mr Configurator 2 software, the value of the "number of pulses" parameter is fixed and determined by the value of the electronic gear.