AB TON to Siemens TON

Hello I'm converting a SLC 5/04 to a S7-1500 both in ladder. My question is the equivilent bits in a Siemens TON.

.DN = .Q
.TT = ?
.EN = ?

Are there equivilent bits? If not, how would make code to get the same thing done?

Thanks!

Yes .DN = .Q

.TT and .EN don't have equivalent bits. (Except maybe for the .EN see below *).
You can create them yourself though.
Place an intermediary coil (#) in front of the IN pin. The variable that you assign to the intermediary coil is then the equivalent of .EN.
You generate the .TT by combining .EN and .DN, i.e.
.TT := .EN AND NOT .DN ;

*: I have never done it, but maybe you can query the .IN directly and omit the intermediary coil. But since that is an input variable, I think that possible the compiler will complain.

Behavior of Siemens IEC timers is different from AB timers as well cf. here.

Thanks for the article! I have been using .Q in the program, I'm going to switch that out now

Maybe not the best way... but you can use greater than and less than and do a compare to the timer value, I did it last week in a Automation Direct, just a simple greater than 0 was TT

geniusintraining said:

Maybe not the best way... but you can use greater than and less than and do a compare to the timer value, I did it last week in a Automation Direct, just a simple greater than 0 was TT

Click to expand...

That's a nice approach if the first ms of .TT being 1 does not matter, but it would also need to test whether .ET was less than .PT if it's not self-resetting logic.



A lot depends how the input rung of the timer is driven; it should be possible to get a .TT-equivalent for self-resetting logic, but it might get messy.


I think there are also non-IEC timers; they may behave in a more conventional manner.

drbitboy said:

That's a nice approach if the first ms of .TT being 1 does not matter,

Click to expand...

LOL... man the programs I write are give and take a few minutes

Just as long as I get the signal some time today

Click to expand...

geniusintraining said:

LOL... man the programs I write are give and take a few minutes

Click to expand...

touche'!