Need Help to Understand a Parameter of Parker HPC Servo Drive

It may be that the most significant bit is really a sign, try 7FFF0000 and see if you get the 129878 result.

Hi ignator

I written the value in Pr.35 7FFF0000 and found that motor continously run and did not stop. So i stopped it by self.

I did some more tests and found following results.

1) Pr.35 "high" part 0000, "low" part 1000. Result motor turned 01 revolution CCW.

2) Pr.35 "high" part 0000, "low" part 2000. Result motor turned 02 revolution CCW.

3) Pr.35 "high" part 0000, "low" part 3000. Result motor turned 03 revolution CCW.

and the same for next numbers.

1) Pr.35 "high" part FFFF, "low" part 0000. Result motor turned 16 revolution CC.

2) Pr.35 "high" part FFFE, "low" part 0000. Result motor turned 32 revolution CC.

3) Pr.35 "high" part FFFD, "low" part 0000. Result motor turned 48 revolution CC.

and the same for next numbers.

1) Pr.35 "high" part FFFF, "low" part 1000. Result motor turned 15 revolution CC.

2) Pr.35 "high" part FFFE, "low" part 1000. Result motor turned 31 revolution CC.

3) Pr.35 "high" part FFFD, "low" part 1000. Result motor turned 47 revolution CC.

and the same for next numbers.

Now it has been concluded that Pr.35 low part values subtracts into high part value. But still did not understand the rule.

I can't load the link to the parker manual. Again, if you convert 7FFF0000# to decimal, and divide by 4096 you get 524272 or 7FFF0#. Per what you indicate, this will be the number of turns of motor shaft revolution. How fast is the motor spinning? You said it ran continuous. I know nothing about this controller. But this is clearly a hex number in a double word register. I can only assume that the most significant bit is a sign bit, that would be the 80000000# bit position. This makes the number negative to a microprocessor unless they coded it to be an unsigned integer.

So for 7FFF0# revolutions, what RPM is the motor spinning at. It may take a very long time if spinning slow. e.g. 524272 revolutions/2000 RPM = 262 minutes, or 4.3 hours. Your additional test vectors, all used FFFxxxxx# leaving the most significant bit set. Do you understand binary microprocessor number systems?

I'm going to guess that the 4096 is a shaft encoder with 4096 pulses per revolution. Note the FFFFFFFF# is -1 (and would turn 1/4096 revolutions), you may not even see this, and I assume that the motor will run in the opposite direction. Does it, make it bigger then -1, like FFFFF000, that should make it turn 1 rotation (-4096) in the opposite direction. Compare this to 80001000 this will tell you if they are using 2s compliment numbers. Note that the calculator you use may not understand negative numbers. It will convert a negative decimal to hex, but not the other direction. The one with windows does not (at least not win2000).