#167 - Wiring some Digital Input sensors

Digital Input sensors are very common in the industry, and they can inform the system about different types of information. Here below some of the most common examples.

Examples:

> Cabinet Door Switch Disconnector: 1-wire connection

The Normally Open (NO) auxiliary contact has +24V on the 11 connection and is wired to a Digital Input connection on the terminal 14.

> Motor Local Isolator: 1-wire connection

The Normally Open (NO) auxiliary contact has +24V on the terminal 13, and it is wired to a Digital Input connection on the terminal 14.

This is similar for wiring Circuit Breakers (3P, 3P+N).

> Presence Sensor with Emitter and Receiver units: 1-wire connection

Power supply: +24VDC to emitter (L+) and to receiver (L+) 0VDC to emitter (L-) and to receiver (L-) Signal: receiver NO (Out) to DI

> Limit Switch: 2-wire connection

Sensor terminal 11 -> input 9 (L+) // sensor is powered by the DI card Sensor terminal 12 -> input 1 (DI0)

> Push-buttons are typically either 1-wire or 2-wire connection. Normally a 2-wire connection is done and then the +24V is jumped to the other PBs that are in an 1-wire connection.

> Presence Sensor: Magnetic 3-wire PNP (NO) in a 3-wire DI connection

Sensor wire 1 -> input 9 (L+) // sensor is powered by the DI card Sensor wire 3 -> input 1A (AUX) Sensor wire 4 -> input 1 (DI0) This is also the configuration for an inductive sensor with positive switching, where the positive output signal to L-.

Note:

It is good practice to add a fuse when bringing external sensors to the control cabinet. The fuse can protect the system against overcurrent, short-circuit or electrical faults.