QUESTION
Can any one help with the design of a timer that would turn on a small DC motor for 1 minute, followed by a variable 20 - 40 minute rest period, to cycle continuously.
I am fully competent in building the building side, but the maths involved escapes me.
REPLIES
AnalogKid2DigitalMan
There are off the shelf units to do so if interested, digital time delay cycle timers that have programmable on/off times and number of cycles to execute with the option of repeat indefinitely.
Macromatic TR-63xxx or TR-65xxx repeat cycle timers, about $90 from Newark
https://www.macromatic.com/literature/catalog/time-delay-relays/
Also came across an Amperite 12DF/FHDFA for about $55, also from Newark.
These may be overkill (handle up to 10A loads), just a suggestion if you need a minimum of hassle.
SOURCE
https://www.eng-tips.com/viewthread.cfm?qid=105658
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