Posted 24 Jun 2014 Hi All I have a program where I have a Solenoid Valve controlled by a Digital Output. The tricky part is getting it to heat up 1.5°C/min starting from 40°C to 100°C. I have tried to make sense of it but I am battling to figure it out. Could someone please guide as to what instructions I could possibly use? Share this post Link to post Share on other sites
Posted 24 Jun 2014 What is your PLC, do you have a controler or a temperature input card? If you have a temperature controler, I recall on E5ZN that we can control the rate of change (ramp). If you have a temperature input card, you could use the PID and TPO instructions. And you could raise your SV 0,5°C every 20 seconds. Or 0,1°C every 4 sec, etc. Share this post Link to post Share on other sites
Posted 25 Jun 2014 I am using a CJ2M PLC with a CJ1W-MAD42 analogue card. The temperature is a is read as 0-10V signal. I tried to use a BCD add without carry instruction (+B). Problem is when I add #3(using 3°/2mins) to 40 it makes the new value 49. Which could have something to do the fact that BCD only goes up to 1001. I am going to try the binary add to see if that will work. Share this post Link to post Share on other sites
Posted 25 Jun 2014 If I remember correctly the process value from the MAD42 is in Decimal. You should verify this from the manual. Also, be sure you are monitoring the values in CX Programmer correctly. You can select from Decimal, Signed Decimal and Hex. Share this post Link to post Share on other sites