May be this question was asked before but i searched this Forum but could not find any satisfying answer.
I want to control a water valve according to a tank temperature in my automation task. details are ; Tank temperature Set Point (SP) : 25 degree , allowed band width is +, - 2 degree (27-23) .my high limit is 35 degree and minimum tank temp is. 10 degree .
I want my water valve fully open %100 at 35 degree and fully closed at 10 degree.
I studied this problem but coulndt solve. in FB41 manipulated value LMN goes suddenly to 100 when temperature goes over 27. and goes suddenly to 0 when temp. below 23.
for example I want my valve to open % 70-80 when goes over 27.
How can i configure these parameters in FB41. also information i used are Gain :1 , PV_FAC :1 , LM_HLM : 100, LM_LLM : 0, TI time :20 sec, TD time 20 sec. no manuel control selected.
İ called also this block in OB1.
Please inform me as soon as possible because now the task is controlled manually.