Fan Timer

[vitzwaters]

I have a coldroom fan which must start running upon start button. At the start of running process, a timer should be activated to countdown 3 hours. Timer must be set once by designer, users must not adjust process timer. When there is power Cut, the timer must not restart, but must continue counting down. Any maintenance time must be able to stop the fan, and start it during the 3 hour process but, the timer must never stop count down or be reset during such interferences. Process runs for 3 hours and stops for 2 hours and repeats for 24 hours. Help. I proposed electromechanical timers( See Attachment) but my idea was nt welcome coz of use neglegence in process.

 

[MacGyverS2000]

Sounds like a useful job for one of those "smart" PLD type controllers. Plenty of threads here about where to get them...

Dan - Owner

http://www.Hi-TecDesigns.com