Diamond Systems OPMM-1616-XT 16-Channel Optoisolated Input & 16-Ch Relay Output PC/104 Module

Field signals from switches, sensors and contactors often sit at voltages and ground potentials that should never reach the computer’s logic. The OPMM-1616-XT is the Opal-MM-1616 module from Diamond Systems: a PC/104 digital I/O board built for industrial applications that need isolation between the computer and the external signals it monitors and controls, with 16 optoisolated inputs and 16 relay outputs.

Each input accepts 0 to 30 V DC through current-limiting resistors, with 8k input impedance, logic 0 up to 1.5 V and logic 1 from 3 to 30 V. Either or both banks of eight inputs can generate an interrupt when any input changes state, and Diamond’s Universal Driver software lets your own code run when the interrupt occurs. The board withstands 500 V DC or AC between the I/O lines and the rest of the circuitry, and no channel shares a signal trace with another, so every channel is isolated from every other.

The 16 relays are SPDT Form C, each with common, normally open and normally closed contacts, switching 30 V DC at 2 A or 125 V AC at 0.1 A resistive, up to 30 W DC. Operate and release times are 5 ms maximum with break-before-make action, and the relays are rated for 10,000,000 operations. All relays start in their power-off state at power-up or reset. Inputs use one 34-pin header and the relays two 26-pin headers. The PMM-P offers relays only, and the IR104-PBF raises the count to 20 inputs and 20 relays.

The OPMM-1616-XT runs on +5 V, drawing 70 mA typical with all relays off plus 28 mA for each active relay, and operates from -40 to 85 °C. It stacks on the PC/104 ISA bus of Diamond hosts such as the HELIOS SBCs, and sits in the same digital I/O range as the GPIO-MM-XT series.