Hi guys, 

I am new to Siemens PLC programming and I appreciate if you could help me.

What is the best way to run a job by receiving a signal. I have a S7 300 CPU connected to ABB 800xa. When ABB sends a signal, certain task needs to be done which is controlled by s7 300. Should I program the task in one of interrupt OBs or I should just make a Function Block and call it when the signal is sent?

I really appreciate your help.

Cheers

Hi

If you are looking for a programming manual look at  Programming with step 7 .

Your program needs to be written in an "OB" anyway but its up to you to use structured programming or linear . use above link

hi

it depends on how fast you have to react. 

I will describe the two possibilities you have mentioned. 

#1 read the input, you get from the ABB. Do a conditioned Call in OB1, e.g. FB1 and do your tasks in it. 

in this case the in the cyclic Programm(OB1) your tasks will be done when it is in sequence. you have the possibility to execute it every cycle, or call it with a positive or negative edge only once.

#2 HW-Interrupt - When a Input on a digital input module is coming/going an Interrupt-OB, e.g. OB40 is called. You can do your tasks inside it. But the OB is only called once, when there is a positive or negative edge.  

I guess, like Daniel already said, #1 would be more practicable for you.

hope this helps,

regards,