4-Channel 5V Relay Shield for Arduino

The 4-Channel 5V Relay Shield allows your Arduino-compatible microcontroller to switch high-power circuits and equipment using low-current control signals. Featuring a direct plug-in shield form factor, it eliminates the need for messy patch cables and supports stacked expansion. It is an ideal switching solution for makers, students, and hobbyists building smart home automation and SCM control projects.

Stackable shield design

Built to the standard Arduino shield interface and shape, this module mounts directly onto compatible motherboards to simplify project assembly. The pass-through header design allows you to continue stacking additional expansion boards above it.

Relay specifications and operation

The board features four 5V DC relays (model HJR-4102-L-5V) offering high-drive control compatible with 5V or 3.3V logic signals. Each relay provides high-power screw terminal connections broken out to normally open (NO), normally closed (NC), and common (COM) contacts, accompanied by dedicated red LED status indicators.

Mounting and installation notes

Three M3 screw positioning holes are included on the PCB for secure mounting in project housings. When pairing with an Arduino Uno, ensure the underside of the green terminal blocks does not short against the raised metal USB connector casing.