CJ1M Contacts and Timers

[Nicholas Christian 0]

Hello everyone,

Is it possible to make the address of an open/closed contact the name/address of a timer? Or, rather, how do you link a contact to a timer?

I'm working with a CJ1M CPU-11, and I think the available commands in CX-Programmer vary from PLC to PLC.

Thank you for your time and help, it is appreciated. God bless.

[Mendon Systems 22]

Not entirely sure what you are asking but ......

You can use any contact format of a timer that you want (NO or NC, and differentiated ON or OFF). The contact identification for timer #10 would be T0010. The mnemonic would be LD T0010 for a NO contact.

If you are defining a symbol for a timer be sure to define it as a BOOL not a TIMER. The TIMER object type only applies to the CJ2M, but CX-P will default to TIMER for other CPU types also.

[Nicholas Christian 0]

Sorry about that. Thank you for your reply!

I'm confused because I'm studying a ladder logic program and I see that it contains the following: a normally closed contact labelled TIM000. The corresponding Timer, TIMH000, is on the same rung of logic. Can you tell me what is happening here? I saw that and thought the contact's address was simply a timer name.

I should clarify also that this ladder logic is not from a CJ1M PLC. I'm trying to learn from it and apply it to a CJ1M.

Thank you again for your time and help. It is appreciated.

[BobB 58]

It is a timed, automatic reset I would suggest. Probably used to create a timed pulse.

[Mendon Systems 22]

I agree with Bob. That description sounds like a timer that is being used to generate some sort of clock pulse. The timer contact will be true for one program cycle whenever the timer expires. For example: if that timer is set to 5 seconds then the timer contact will be true for one scan every 5 seconds. There will be at least one more contact of that timer used somewhere else in the program as a clock pulse, probably to start (or stop) some logic sequence.

[Nicholas Christian 0]

Thanks guys! That makes sense.

Do you know of a tutorial or resource I can use to learn how to do just that? I only have the completed logic, but don't know how do it for a CJ1M controller.

Thanks again. I appreciate it.

[BobB 58]

Here is a simple example - a self resetting, free running timer set at 0.5 seconds. On the rising edge of the timer output 1 will be incremented into D1000. the timer will then reset and commence timing down again.