How to find the right IO Blocks AI guide

What the AI looks for in IO Blocks

Levels per point

For 3-wire sensors, use a three-level block that carries signal, +24V and 0V on one footprint. Two-level blocks suit 2-wire devices and actuators. Matching levels to the device wiring avoids extra potential-distribution blocks and keeps each sensor on one compact block.

Signal polarity and indicator voltage

LED and diode versions must match the I/O voltage, usually 24 VDC, and the input type, either PNP (sourcing) or NPN (sinking). An LED block with the wrong voltage or polarity stays dark or misreports the state, and this is the most common ordering mistake here.

PLC cable or connector compatibility

For interface or breakout modules, the connector type, pin count, pitch and pinout must match the PLC card or its prefabricated cable, either from the same family or with a documented pinout. A connector that fits physically but has the wrong pinout puts field signals on the wrong terminals.

Connection technology and wire range

Choose push-in, spring or screw clamp to match your existing panel. Confirm the rated conductor range covers your sensor leads, including ferruled stranded wire. Fine sensor leads that sit below the clamp's range work loose, and mixing clamp types complicates panel maintenance.

Mounting and accessories

Most IO blocks mount on 35 mm DIN rail. Buy end plates, end stops, jumpers and marker strips from the same series. Jumpers and markers from a different series or brand rarely fit.