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- Delay Relay, Active time = 1.1RC = e.g 47UF * 500K = 1.1 * 500,000 * 0.000047 = 25.85
Capacitor 47UF connect to Threshold Resistor 500K connect to Trigger
Flashing Blue Red LED Alarm
- Module combines of NE555 and CD4017, when the 1st, 3rd, 5th pulse comming, blue LED flashing, and when 2nd, 4th, 6th pulse comming, red LED flashing. When 11st, 13st, 15th pulse comming, blue LED flashing, again and again. Then it looks like alarm light.
- Change trim pot can change frequency.
Calculation T=1.1*500000*0.000047=25.85 seconds maximium
1.1 constant value 500 000 = 500K = trim pot maximium resistance value 0.000 047 = 47UF = fixed on board capacitor
- Re-count (top) = re-count time of delay
- Reset = reset relay status