how many timers and counters can we have ?

[leonlai]

Hello,

I have a stupid questions
How many timers and counters we can have or can we create more timers and counters ???
For example in micrologix 1400, by default in RSLogix 500 I see there is T4:0 to T4:15 & C5:0 and C5:1;
I click properties to add more T4 and C5 (like T4:32 and C5:5)
but is it right ??? will the micrologix regconize them ?? or there are only 16 bits of T4 and 2 bits of C5 and no more ???

Thanks

[widelto]

yep go ahead, nothing will be broken

[bernie_carlton]

You can place into code up to T4:255 or up to C5:255. The already established tables will be automatically expanded to hold the highest number you enter.

In a like way you can right-click on the data table in the left column then, under properties, assign either the number (up to 256) or the last location (up to XX:255) in that table.

If you need yet more of these you can create more data tables by right-clicking on 'Data Files' and selecting 'New'. Fill in the (currently unused) number and type of the file. Enter the number of entries (this can always be expanded just as in the default files.)

[leonlai]

Thank you Carlton

[TConnolly]

It may be helpful to remember that a timer and a counter is not a device. It is a computer instruction that operates on a location in memory. As such when you add more timers or counters you are allocating a piece of memory to be used. Your only limitations are the limits of the file size (256 elements), which is an addressing limitation, not a memory limitation. By adding more files of the desired data types you can have as many bits, timers, counters, integers, etc. as you need up to the memory limits of the controller model you are working with.


In the AB line only the bottom dwelling Micrologix 1000 has a fixed timer/counter limitation. Some other PLC manufacturers pre-allocate memory for specific purposes so with those brands you may find that your data types are not expandable, although most are generous with the memory allocation.

[Lancie1]

In the AB line only the bottom dwelling Micrologix 1000 has a fixed timer/counter limitation.

The caveat "in modern times" should be added. Ocassionaly someone here will dig out on of the older Allen Bradley PLCs such as the PLC2 or the SLC 100. Then you are back to the "limited number of fixed timers.