Micro820 with 2080-MOT-HSC

[chikhim]

Hello everyone.
I'm having some error on the pulses read by the HSC card.
I'm using the 2080_MOT-HSC as a pulse counter; in the CCW in using HSCE_CFG for configure the HSC and HSCE instruction to get the accum pulses.
For calculating the rate Im using a single Timer to get the rate every 1 second.
The HSC is counting and the HSCE Instruction indicates the accum.
These are the issues:
First, the rate calculated using the timer vary more than the rate calculated by the HSCE instruction. I was thinking maybe in one scan lost the count of pulses, the scan is 5 ms and the max is 8 ms.
The other thing is that if I run the system to 1 HZ, I got a vary RPM about +- 3 (this is for the vary rate), but if I run the system faster the vary is bigger and doesn't seem consisted.
I set filters on the input, i change many parameters but the RPM vary is the same.
I found information about the 2080-MOT_HSC pulse counting error, but it says at 10 Hz the error is 0.001 % but I got errors starting at 1 Hz.
Anyone have had problems reading pulses with HSC?
I attached the HW Configuration.

 

[chikhim]

I solved it.

The wiring was good.

The way I was calculating the frequency was comparing the accumulator every second. I had some different values every X time Because the Timer was running on Main program while the PLC Scan.

I Thought at the beginning It was a pulses counting error; I used an oscilloscope to measure the real frequency of the pulses and compare with the rate1 output of HSCE instruction, the frequency matched so I prefer to use the rate1 output from HSCE instruction instead of calculate it with a timer.