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General => Technical support => Topic started by: Mikkel Steen Pedersen on September 30, 2002, 02:37:02 AM

Title: Measuring pulse frequency
Post by: Mikkel Steen Pedersen on September 30, 2002, 02:37:02 AM

I'm using a T100MD1616+ PLC for my project, among other functions i want to measure the rotation speed of a wheel (just as descriped in the user manual page 1-10).

I'm using an inductive sensor and the input works fine when i count the pulses normally.

When use the PMON, PULSEFREQUENCY commands nothing happes (not even an error code)

What can be wrong???

- pulse frequency range 0-200 Hz is that to slow?


Regards

Mikkel

Title: Re: Measuring pulse frequency
Post by: support on September 30, 2002, 10:29:41 AM

Pulse measurement channel #1 maps to input #3, PM channel #2 maps to input #4.

You need to execute PMON 1 once only. Then connect your pulse signal to input #3, and whenever you execute

X = PULSEFREQUENCY(1)

the frequency of incoming pulses will be assigned to variable X.

The same goes for PMON 2 and  PULSEFREQUENCY(2). However, remember that you should connect the pulses to input #4 in this case.

TBASIC is a generic language and PM1 and PM2 happen to share the same inputs terminals as input #3 and input #4 for T100MD+ PLC.

Title: Re: Measuring pulse frequency
Post by: Mikkel on October 08, 2002, 08:59:18 PM

I've done what you described and it now works perfectly. ;D


Regards

Mikkel