Each module has 8 M12 connectors which are used to connect the sensors or actuators.
For the TSX EEF 16D2 module with 16 inputs, an M12 connector is used for two outputs.
A label on the rear of the module shows how to connect all of these connectors.
NOTE: the label is not accessible on a mounted module.
The M23 connector is used for the remotely supplied bus.