Tom@Pton (Customer) asked a question.
HSC CLICK PLUS
I've set up my own counters in the past to determine RPM or lack of rotation. Low speed.
Bought a PLUS and a dc input so I can try my hand at higher speeds. No switch yet.
I set up Y1 out put to turn on every second via SC7. That fed input X1 as my counter input. DD1.
The closest DD1 comes to my expected 60 RPM is 120.
What am I counting?
Are you sure you're using SC7 and not SC6?
Yes, that was the first think * checked.
Just tried again to make sure. Could have sworn...
SC7 does get me 60 on occasion, but generally something much higher.
SC6 gets me the 120 on occasion, but generally something much higher.
It might help if you could provide a copy of your test program.
Are you measuring the period between two rising EDGES of SC7, or the time that SC7 is ON? in the latter case that is 500mS ON then 500 mS OFF in each second. 60 seconds divided by 500mS is of course 120
I don't have any idea why you are getting changing results. I don't have a PLUS to experiment with. I would double check wiring, loose connection maybe? , and since I have one, I'd put a 'scope on X1.
as bcarlton wrote seeing the code would help. Are you using the high speed functions or conventional ladder? if the HS, it looks there there are three options, ITV or DUR and do the math yourself, or FRQ.
If just experimenting, I'd wire three inputs together and try all three functions to see how they compare
What I have now.
The program is C20, sc7 to y1.
+ 24dc to x1 via y1. C208DR4V
HSC:
Freq, DD1, RPM, Pulse =2 (I changed it from 1)
Pulse of 1 gives me 120.
value goes all over.
Y1 is a relay output. I'm suspicious that contact bounce may induce inconsistent counts. It might be different with a solid state output. But I don't have a Click system to test.
I did wonder about contact bounce.
The load of the DC input barely equals the required minimum load for the relay output. Maybe a 1k ohm resistor in parallel across the input (X1 - C1) might help (adding 24 ma to the load current).
For RPM try a higher number of pulses. 10 should give you 6 RPM