16-Channel Relay Module with Optocoupler for Arduino and PLC

A panel with sixteen loads to switch usually means a stack of small boards and a lot of jumper wires. This module puts the sixteen relay channels on one board, with optocoupler isolation between the control inputs and the relay side. It is aimed at Arduino and PLC builders wiring lights, pumps or valves.

Sixteen Channels, One Board, One Control Feed

✅ Sixteen outputs, one board Group sixteen circuits on a single module instead of stacking four-way boards along the rail.

✅ Isolated control side Optocouplers sit between the logic inputs and the relays, keeping coil switching off the controller pins.

✅ Arduino and PLC control Drive the channels from an Arduino sketch or a PLC output, whichever the panel already uses.

✅ Voltage options Choose the 5 V, 12 V or 24 V version that matches the supply already in the enclosure.

The wiring follows one path per channel: a controller output feeds an input, the optocoupler carries that signal across the isolation barrier, and the matching relay contact closes the load circuit. Sixteen of those paths sit on one board with a single supply feed.

Isolation earns its place with inductive loads. Pumps, solenoids and contactor coils produce a spike when they switch off, and the optocoupler is the part that keeps that spike away from the logic pins. It does not replace fusing or a correctly rated contact, but it keeps switching transients off the controller side.

Voltage is the decision to make before ordering. A 24 V module on a 5 V rail will not pull in, and a 5 V version fed from a 24 V rail is worse. Match the module to the supply already inside the enclosure, then count the loads you need to switch.

Technical details

• Channels: 16 relay outputs
• Output type: Relay contacts with optocoupler isolation
• Supply options: 5 V, 12 V and 24 V versions
• Control compatibility: Arduino, PLC and automation controllers
• Condition: New

Check the supply voltage in your panel, then choose the 16-channel module that matches it.

See more: explore more smart home control gear