I am using LED display board that can store 16 different temperature setpoints. sends these inputs to a control card to maintain the POT temperature. The Analog controller takes thermocouple inputs and displays in these boards.

The communication is through MODBUS. I observed a typical variation in ambient temperature as 36, 40, 65, 80, 100, and after that it stats UP and down values.

I changed my controller and thermocouple and plug and socket. Still Problem not identified

Sometimes it comes after one month this disappears. Also it occured after changing all the cards

CAN U SUGGEST ME HOW TO FIX THIS.

 

Hi,

You have not mentioned the controller your are using. i suspect stack overlay problem. please check you RAM and stack area defined in your code or defalut controller configuration.

 

yes,check the controller.
http://www.ledtop168.com maybe there some engineer can help.