ML 1100 High Speed Counter not counting in high speed

Hello everyone,

I am using a ML1100 and a 2048 pulse incremental two channel encoder.

I have set up the high speed counter and the ML1100 according to AB's specifications. The HSC:0/acc value does count up and down (depending on direction of the encoder shaft), however, the HSC begins to stop counting pulses after the shaft speed exceeds 90 deg / sec, roughly.

This is 512/s or 500Hz input signal. Why does the HSC, which is supposed to be 20KHz input frequency max, not read an input signal of such low frequency?

I have tried going offline / online to modify the IO settings (input filter frequency) but I am unable to change the input filter frequency regardless of whether I am offline or online.

Can anyone give me any tips? I'm stumped.

Thanks,

Jon

Make sure the 'Base Type' is set to 'BWA', not 'Any Base'.

bernie_carlton said:

Make sure the 'Base Type' is set to 'BWA', not 'Any Base'.

Click to expand...

Thanks! That did it. I haven't tested the new settings yet but I'm confident the counter will now respond properly.

My curious nature now requires me to ask what the difference is between the various base types.

JonHopper said:

My curious nature now requires me to ask what the difference is between the various base types.

Click to expand...

See page 12 and 157 of manual below.

http://literature.rockwellautomation.com/idc/groups/literature/documents/um/1763-um001_-en-p.pdf