Inter-M HDCC-400 - Manual (Page 12)

2.5 Termination.
The first and last devices in an installation (dome and keyboard controller) must have the data line
terminated by setting the DIP switch. Without proper termination, there is potential for control signal
errors. Total length of the cable for communication should not exceed 4000ft (1 .2Km).
Refer to Figure 6 for setting the dome camera and keyboard controller termination.
Figure 6 – Termination