It seems to happen only sometimes.
But i have bigger problem now, the ladder logic executes perfectly as i want it when i simulate it in tri-logic 6.3.But when i write the program to the FMD88-10 plc and connect it to the HMI keypad and LCD and try to execute the ladder logic it does not seem to work at all. I have used plently of input,outputs and timers in my program.Would you be able to run the ladder program in your PLC and tell me if it runs fine?