Step 7 Multi-instance question...

Hi,

I'm doing some experimentation to try and expand my knowledge of Step 7 (specifically multi-instance stuff).

I've created an FB with two SFB 4's (TON) in the STAT area.

They are called:
firstTimer
secondTimer

I've then created another FB and put the first FB in the STAT area of that under the name: myTimers

From this FB I can access variables called:
#myTimers.firstTimer.IN
#myTimers.firstTimer.PT
etc etc

But I can't seem to get the timers to work. Is this possible to have a kind of 'nested' multiple instance???

It might simply be a problem with my code. The "myTimers" block in my Multiple Instances folder doesn't have any inputs or outputs, it's just a block.

My code in the main FB looks like this:

As I said, maybe it's just a problem with my code or maybe I'm missing something else.

Can anyone clear this up for me?

Many thanks

Are you calling the IEC timers in the multiinstanced FB ?
It is not enough to set aside the data to be used by the IEC timers.

Are you testing it with PLCSIM ?
There have been problems with the IEC timers in several versions of PLCSIM.

JesperMP said:

Are you calling the IEC timers in the multiinstanced FB ?
It is not enough to set aside the data to be used by the IEC timers.

Are you testing it with PLCSIM ?
There have been problems with the IEC timers in several versions of PLCSIM.

Click to expand...

Hi Jesper,

You're a genius!!

I put in the call out of the Multiple Instances folder to myTimers and the software worked!!

(I am using PLCSim by the way. v5.4 SP4 and it seems to be ok so far.)

Many thanks

John ;-)