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General => Technical support => Topic started by: mhampson on March 30, 2004, 05:00:19 AM

Title: Pulse Frequency Measurement Problem
Post by: mhampson on March 30, 2004, 05:00:19 AM

I am trying to measure pulse frequency on my T100MD+ on channel 3 and am getting a 0 reading at all times. My actual pulse frequency should be around 5 (will be higher when installed). I have a "PMON 3" in my setup function which executes on the first scan, and every second thereafter, I have a function that runs which executes a "A = pulsefrequency(3)" instruction. A is always 0. I am using digital input #3 and can see the input light flashing rapidly, and I am not using the input for anything else (HSC etc.) in the program.

What am I missing here? I am going to try another channel and poke around with some things this morning. This is the only thing lacking before my customer trial.

Thanks,
Michael Hampson
XL Automation, Inc.

Title: Re:Pulse Frequency Measurement Problem
Post by: support on March 30, 2004, 11:28:24 AM

Input #3 is mapped to Pulse measurement channel 1. So you should execute PMON 1 and it should work.

Title: Re:Pulse Frequency Measurement Problem
Post by: mhampson on March 30, 2004, 02:54:05 PM

Oh, geez, I figured it was something stupid . :P  I now see that the channel numbers are noted in the installation guide, rather than being related to the digital input number. If I only had a brain!

Thanks for the quick response.

Michael

Title: Re:Pulse Frequency Measurement Problem
Post by: jung-honey on May 18, 2004, 06:09:13 PM

first, Digital input #3 is channel #1 for pulse measurement

so set like below

  PMON 1

and then press PLC RESET button on On-line Monitoring

then u can c what u want