Good day everyone, please help with setting up the Logo.
I want to control the chamber temperature (-5 to + 35 ° C adjustable).
I will set this temperature from TD. Unfortunately I don't know how to do this:
1) the temperature is lower than the set temperature - start the heating
2) the temperature is higher than the set - start cooling
Thank you for the idea

hello ixo, maybe the schema attached will help.

I need to enter a value between -5 and +35 ° C using TD. depending on the current temperature, I have to decide which controller will be active

 ideally, a three-state controller would be used. unfortunately there is no such block in LOGO

valsidal.alu

I need to enter a value between -5 and +35 ° C using TD. depending on the current temperature, I have to decide which controller will be active

 ideally, a three-state controller would be used. unfortunately there is no such block in LOGO

Maybe you are just searching for an easy solution like the program in the attachment.
If temperature is higher than setpoint + 1,0°C, cooling is started
If temperature is lower than setpoint, cooling is stopped
If temperature is between setpoint +/- 1,0°C, nothing is done
If temperature is lower than setpoint - 1,0°C, heating is started
If temperature is higher than setpoint, heating is stopped

You can setup the difference for starting and stopping as you want. This is a three-state controller for me.

Regards, Scorp