For led, we can use power from the arduino board (≤ 5v).
41+ Arduino Relay Board Schematic Background. The arduino can be programmed to turn on the relay when a certain event occurs, for example would be grateful for a schematic of the circuit. This relay module provides four relays that are rated for 7a at either 28vdc or 10a at 125vac.
5V Relay Board 8 Channel Connections .. HELP from i47.tinypic.com
Each relay has a normally open (no) and a normally closed (nc) the following schematic shows how to connect the module to an arduino, i have only shown one device (lightbulb) connected to one relay. Double check the schematics diagrams and breadboard wiring for any then connect the relays input pin (the pin comes from the transistor's base pin) to the arduino's digital pin 13. This relay module provides four relays that are rated for 7a at either 28vdc or 10a at 125vac.
Alternatively if the arduino board is powered via 12v to its power plug, limit the number of 10ma reed relays to less than 6 as the on board 12v to 5v unfortunately there is no schematic provide for the very inexpensive module, so you need to test it to see if it is suitable for use with a 3.3v output from.
Basically, a relay is an electromagnetic switch. Qunqi 4pcs 5v 2 channel 5v relay module with optocoupler low level trigger expansion board for arduino uno r3 mega 2560 1280 dsp arm pic avr stm32 raspberry pi. Looking to make a relay board yourself? Assemble all the parts as shown in the schematic diagram.
