The CB15 terminal board connects to the DB15 connector on applicable LabJacks (not the U12). It provides convenient screw terminal access to the 12 digital I / O available on the DB15 connector. The CB15 is designed to connect directly to the Labjack (see image below), or can connect via a standard 15-line 1: 1 male-female DB15 cable (not included).
The green LED on the CB15 is directly powered by the 5 volt supply (Vs) from the Labjack, so it Should be lit whenever the CB15 is connected to a powered Labjack.
The CB15 PCB is mounted to a piece of Snap Track. The Snap Track is DIN rail mountable using TE Connectivity part #TKAD (not included).