5-14
Cisco MGX 8260 Hardware Installation Guide
78-10966-02
Chapter 5 Connecting the Cables
Connecting Visual and Audible Alarms
Connecting Visual and Audible Alarms
To connect alarm relay contacts, follow these steps:
Step 1
Prepare a custom, multiple-conductor alarm cable for visual or audio alarms in your facility. Terminate
this cable in a DB-15 connector using the pinouts shown in
Appendix A, “Cable and Connector
Reference.”
Step 2
Connect the DB-15 cable to the alarm connector on the SCC back card.
Step 3
Connect the other end of the cable to a centralized alarm management system (CAMS).
Applying DC Power
Warning
Carefully read all instructions in the
“Electrical Safety Warnings” section on page 2-2
before
continuing with the instructions in this section.
This procedure explains how to connect and apply DC power to the MGX 8260.
Observe the recommended wire gauge and number of power cables. This procedure specifies two 12
AWG conductors for the Supply (–48V) and two 12 AWG conductors for the Return (RTN) wires from
the power source to the appropriate terminal blocks on the MGX 8260. The length of each wire should
be kept as short as possible and the same length. This specification provides the proper conductor
capacity for the MGX 8260’s maximum power requirements (1800 watts).
The supply wires to the input terminals on the MGX 8260 should be protected by a double-pole,
20-amp-per-pole circuit breaker for each circuit. This configuration is shown in
Figure 5-10
. Note that
each circuit (A and B) is connected to a separate power source and circuit breaker.
Caution
Make the connections as shown in
Figure 5-10
.
To connect DC power as shown in
Figure 5-10
and
Figure 5-11
, follow these steps:
Step 1
Disable DC power from the source by switching circuit breakers to the OFF position or removing fuses,
depending on your configuration. Circuit breaker switches should also be taped in the OFF position.
Caution
Make sure that you disable the power source for both power circuits, A and B.
Step 2
Prepare four power cables for each input feed—two for –48V supply and two for RTN. Use 12 AWG ST,
UL 1015 wire with #8 spade lugs for 12 AWG (MOLEX BB-8716-08) for each cable.
Step 3
Verify that the ground lead is already connected as indicated in
Step 5
of the
“Installing the Chassis”
section on page 4-2
.
Step 4
Remove the MGX 8260 power terminal cover from the feed A power terminals and set it aside. (See
Figure 5-12
.) To remove the cover, use a small bladed screwdriver to loosen the two captive screws and
lift the cover off.
