Author Topic: Freq to RPM  (Read 2979 times)

MimmoA

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Freq to RPM
« on: March 31, 2014, 05:24:16 PM »
Hello,
could anyone give me some advice on how to make the most Freq to RPM block ? I connected a speed sensor on multifunction pin 26 but always has a delay in the return to the value 0. it is due to the fact that when you lock the shaft position sensor is not changing state leave the last stored value?
I have used freq input and pinconfig1=2.
best regards
« Last Edit: March 31, 2014, 05:33:55 PM by MimmoA »

bgtwuk

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Re: Freq to RPM
« Reply #1 on: April 02, 2014, 06:18:48 PM »
I would use the Function Block....Freq/Rpm.



Works great...

Bgtwuk

Offline oiltronic

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Re: Freq to RPM
« Reply #2 on: April 05, 2014, 07:38:36 PM »
... always has a delay in the return to the value 0. it is due to the fact that when you lock the shaft position sensor is not changing state leave the last stored value?

Given that this block allows integer frequency values down to zero, and given that the API spec for frequency doesn't specify a lower range, I would say that your guess is correct.  It makes sense that the input frequency will continue to decrease until no input pulses are seen for a full second or two (depending on rounding).

I often use timers and/or limits to help speed calculations maintain their sanity.

Offline BRIan

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Re: Freq to RPM
« Reply #3 on: April 07, 2014, 12:22:49 AM »
If you need to use decimal frequencies, you can calculate these by using the PER signal