Question: what is a 5v relay module?
Answer: 2-Channel 5V Relay Module is a relay interface board, it can be controlled directly by a wide range of microcontrollers such as Arduino, AVR, PIC, ARM and so on. It uses a low level triggered control signal (3.3-5VDC) to control the relay. ... 5V relay signal input voltage range, 0-5V. VCC power to the system.