jims

jimboy

Member
J
Join Date
May 2014
Location
Kilmarnock
Posts
4
Good day all,

I need to count the revolutions of a drum, using a Siemens 135 step 5 PLC, with a digital proxy how do I increment the input bit by one, so that I can use it in the visual screen to display the count.

Regards,

Jims.
 
Hi Jimboy....

Not sure if I can help but noticed you joined the website in 2014 and 3 years later you asked a question :)

Not many people are using Step 5 anymore but your input would be going to a counter and indexing every time the prox is true are you using ladder or STL?
 
Here is my quick take in STL:

Code: 
A E0.0	// Input from sensor
AN M0.0	// Memory of previous status
= M0.1	// One-shot impulse of input

A E0.0
= M0.0	// Store the memory for next scan

A M0.1	// Impulse ?
JCN M001	// Jump past if no impulse
L MW100	// If not jumped past then increment counter
L 1
+I
T MW100
M001: NOP1 // Jump past label
NB. Also add a check for the counter not counting past 32767. I dont remember if an overflow will cause a CPU stop.

Disclaimer: It is more than 20 years since I worked seriously with STEP5 :)
 
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