ADC 19717-A - Manual (Page 28)

ADCP-75-169 • Issue 1 • June 2004
Page 20
© 2004, ADC Telecommunications, Inc.
4.11 External Alarm System Connections
The alarm interface between the HU and an external alarm system is supported by a six-terminal
plug (with screw-type terminals) that connects to a receptacle mounted on the HU front panel.
The terminal plug provides connections to normally open (NO) and normally closed (NC) dry
type alarm contacts for both major and minor alarms. A category 3 or 5 cable is typically used to
connect the HU to the external alarm system. Use the following procedure to install the alarm
wiring and connect it to the HU:
1. Obtain the required length of category 3 or 5 cable.
2. Route the cable between the HU and the external alarm system (if not already routed) and
then cut to the required length. Allow sufficient slack for dressing and organizing the cable
at the HU.
3. Strip back the outer cable sheath and insulation to expose the wires at both ends of the
cable and strip back 0.2 inches (5 mm) of insulation from each wire.
4. Connect the Major alarm wire pair to the MAJOR COM/NC or MAJOR COM/NO
terminals (whichever is required by the external alarm system) on the HU alarm terminal
connector (supplied with HU) as shown in
Figure 19 .
Figure 19. External Alarm System Connections
5. Connect the Minor alarm wire pair to the MINOR COM/NC or MINOR COM/NO
terminals (whichever is required by the external alarm system) on the HU alarm terminal
connector (see
Figure 19 ).
17871-A
ALARM
CONNECTOR
MAJOR ALARM WIRES
MINOR ALARM WIRES
NO
COM
NC
NO COM
NC