Relays are important part of any electrical and electronic circuits. We use relays in control applications, switching applications, circuit protection applications and load transfer applications. Relays are also used to provide electrical isolation between two circuits. This 8-channel Relay module comes with Optocoupler protection is an active low relay module which means that the relay will conduct when the input signal falls below 2V and if it is above 2V then the relay is turned off you can also make it an active module by changing the jumper position on the power module. It can be controlled directly with both 3.3V and 5V microcontrollers easily. You can use it to control both DC and AC lines and it also has LED indicators to indicate the state of operation of the module. It also has high Impedance input pin so not to draw any more current than required from the controller. 8-Channel Relay Module Specifications Optically Isolated relays protect your microcontroller from damage if the equipment being controlled fails 5V 8-Channel Relay Interface Board, each one needs 15 20mA Driver current Equipped with high current relays 10A which can handle upto 250VAC Relay output status indication by LED Back EMF Protection High Input Impedance Product Description Take care of fact that the current flowing does not exceed its rating. Package Contents 18 Channel 5V Relay Module with Optocoupler