4 channel relay module 4-channel relay control board with optocoupler. Relay Output for arduino

   5V 4 Channel Relay Module Board Shield For ARM PIC AVR DSP For arduino Diy MCU Starter Kit

   The new 5V Relay Module

   Can be used as microcontroller development board module can be used as home appliance control

   5 V-12V to TTL control signal

   The control signal DC or AC, 220V AC load can be controlled.

   There is a normally open and one normally closed contact

   A power indicator light

   A control indicator, pull off, disconnect does not shine

   Transistor drive to increase the relay coil control pins high impedance.

   The control pin has a pull-down circuit to prevent malfunction relay vacant.

   1Pcs 4 Channel Relay Module