Cont_c question about temp control in 4 rooms

Hello everyone!

I want to know if i can control temp via cont_c in 4 rooms in the same time.I dont have any hardware so i want to know if i can make this project and how..I use cont_c but something is going wrong for 2 or more rooms...It works well for just one room..So some help will help me a lot..

Thanks

hi Tonis,

for temperature controll usually TCONT_CP or TCONT_S is used. The first is a continous temperature controll with pulse generator. The second is a Temperature controller for actuators with integrating behavior. These blocks are available in S7-300 and s7-1500 PLC´s. Other PLC´s may have other blocks.

For using this blocks more than one time in your program, you need to call it everytime with an own instance-DB. Normally the blocks need to be called in a cyclic interrupt OB, like OB35 

hope this helps, 

regards,

Hi,

Is there multiple temp sensors and one actuator? What PLC you are using? Make a simple drawing for us to have a better understanding of your requirement!

Anyways. As a start see these examples:

Single and Multi Loop Controller Structures (Cascade Control) with PID_Temp

Ok i use cont_c to control temp in a room, i have made the block  and the PID works perfect.My question is if i can control temp with the PID that i made for one room to control temp of the other 3 rooms at the same time.So one PID for 4 different situations.Can i do this with some way or i need 4 PID for 4 rooms?(each room different  setpoint)

Hi,

In S7, in general: 4 independent PID loop needs 4 independent block instance. (Same block but different instance DB)

Anyways, I assume you use S7 1500. See this:

SIMATIC S7-1200, S7-1500 PID control under chapter" 3.3 Add technology object"

Hi,

I hope I understand you. Why not try to create 3 more separate block instance(all together you will have 4 block calls, 4 instance DB, 4 sets of parameters, one block).

Can you make me printscreen of the one PID you have? Just to make sure I understand your concept!