I'm looking for a way to do the following:
Once triggered, the circuit will
- close the first relay (R1) for 10 seconds, then open
- then close the second relay (R2) for 10 seconds, then open
- have a pause of 60 seconds until it can be retriggered.
Electrical Engineering Stack Exchange is a question and answer site for electronics and electrical engineering professionals, students, and enthusiasts. It only takes a minute to sign up.Sign up to join this community
If you realy want a complex solution with 3 555 chips: read the datasheet, configure all 3 as one-shots with a common trigger, one for 10 seconds, second for 20 seconds, third for 80 seconds. Use the first one to activate the first relay (resistor-transistor-diode) AND to disable the second relay (you could use a spare contact of the first relay for that). Use the 2nd one to activate the 2nd relay (unless it is disabled). Use the last one to disable retriggering.
Or: learn to program a microcontroller, maybe an Arduino is a good fit for your level.
555 Timers can only be triggered at one frequency with a specific duty cycle, there are many calculators online which will help you choose the proper components.
As for the 60 second pause until the circuit can be retriggered, it would be easiest to use a simple microcontroller rather than a 555 timer to coordinate this. A 556 timer (which is essentially two 555 timers in one package) could conceivably be used as well.