Relay Temporizador 555DescriptionChip: NE555 Dimension: 68mmX21mm Working Voltage: DC 12V Feature 1. the relay time delay and power supply is connected. 2. delay time is adjustable, (0 ~ 10 seconds) 3. add potentiometer can increase delay time 4. add capacitor C1 can increase latency time 5. with input power light 6. with relay and indicator lamp 7. can control device with AC 220 v / 10 or below. (maximum control equipment 2000 w) 8. stream with relay protection. 9. the delay time formula: T = 1.1 RC. For example: 100 uf capacitance resistance 100 k T = 1.1 * 100000 * 0.0001 = 11 seconds