Hello Auto_Gen,

An image that shows part of a program is a bad starting point. Why not upload the program as a zip file?

Regards Ella_68

I would replace B005 with an RS element. Then you have the option of additionally triggering the heating of the 500l tank on the negative edge of B016 when the target temperature of the 200l tank is reached.

Regards Ella_68

Thanks for repply,

Example 1: Ai1 is 60 deg and Ai2 drops to 50- then heater start and heat Ai2 to 75 ,then switch 3way valve to Ai1 and heat it to 75, then stop the heater 

Ex 2: Ai2 is 60 and Ai1 drops to 50 deg then heater start and heat Ai1 to 75 , then switch the valve to Ai1 and heat to 75 deg , then stop the heater 

 And the main condition is that Ai1 has  priority over Ai2 ( ex: if the Ai1 reach 50 deg when the heater is working on Ai2, switch the valve to Ai1...heat to 75 deg and then switch back to Ai2 and continue heating till 75 deg).

In my original program this was done only "half".

Do you think it is possible what i want?

 Hi AutoGen,

AutoGen_5086219

Example 1: Ai1 is 60 deg and Ai2 drops to 50- then heater start and heat Ai2 to 75 ,then switch 3way valve to Ai1 and heat it to 75, then stop the heater 

Ex 2: Ai2 is 60 and Ai1 drops to 50 deg then heater start and heat Ai1 to 75 , then switch the valve to Ai1 and heat to 75 deg , then stop the heater 

And the main condition is that Ai1 has  priority over Ai2 ( ex: if the Ai1 reach 50 deg when the heater is working on Ai2, switch the valve to Ai1...heat to 75 deg and then switch back to Ai2 and continue heating till 75 deg).

If I haven't made any mistakes, the program in the appendix should correspond to your description. The block B005 sets the priority.

Regards Ella_68

Hi Ella,

I can only thank you! I bow before you! It works exactly as I wanted! thank you a lot for your support!