8 Channel USB Relay Module (USB-RLY16L, Low Power, 16A)

The USB-RLY16L is an 8-channel relay controller engineered for switching high-current electrical loads up to 16A and 277VAC directly from a computer. Featuring latching relays with volt-free contacts, it retains switching states without power and operates entirely over the USB bus without an external power supply. It is ideal for makers, engineers, and students developing PC-based automation, laboratory test rigs, and remote switching setups.

Bus-powered USB operation

The module runs completely from the host USB connection, removing the need for auxiliary power supplies or extra wiring. This low-power architecture streamlines integration into desktop automation systems, equipment test benches, and experimental rigs.

High-capacity latching relays

Eight independent Single Pole Change Over (SPCO) channels handle switching currents up to 16A, voltages up to 277VAC, and a maximum power of 5000VA. The latching mechanism preserves relay states even when power is disconnected, ensuring reliable process continuity.

Volt-free screw terminals

Relay outputs feature volt-free contacts broken out to labelled screw connectors for position 0, common, and position 1. This delivers safe electrical isolation between host control logic and high-power external circuits.

Visual LED status monitoring

Dedicated red status LEDs beside each channel provide immediate visual confirmation of the relay state. An active LED indicates position 1, while an unlit LED indicates position 0, speeding up diagnostics during testing and deployment.

Robust operational specifications

Engineered for reliable performance across a temperature range of -40°C to +70°C, the board features a contact resistance of 50 mOhms at 1A 24VDC. The package includes one USB-RLY16L module ready for direct hardware integration.

Downloads & documentation

• Datasheet
• usb-devtech-inf
• RelayModulesSetup