Hellooo

I want to make an alternate ventilation where 4 fans run for a while and then the other 4 run. I use tia portal with a dimmer that controls 8 monitors on which 8 fans are put. Thanks for your help

CaOd

Hello,

you can do this in a lot different ways.
It's depending of your PLC which you use.

One solution  for a 1200/1500 is that you use a frequency generator, e.g. LGF_frequency from  the 

Library of general functions (LGF) for SIMATIC STEP 7 (TIA Portal) and SIMATIC S7-1200 / S7-1500 

You parameterize them so that you have a signal which change every 200 seconds.

Then you can switch with a logic that when the output signal of the generator is FALSE Fan 1 to 4 is running and when the signal is TRUE, the other fans are running.

Also work it with a clock generator with 2 timers.

There are so much more solutions for this challenge. This solution is only one suggestion.

Hope this is a little bit helpful.

regards
CaOd

 Thank you very much !