Cisco Systems 15454-FTF2 1.15 Power and Ground Description

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Cisco ONS 15454 Reference Manual, R8.5.x
78-18106-01
Chapter 1 Shelf and Backplane Hardware
1.14.5 Pilot Fuse
Caution Do not operate an ONS 15454 without the man datory fan-tray air filter.
Caution Inspect the air filter every 30 days, and clean the filter every three to six months. Replace the air filter
every two to three years. Avoid cleaning the air filter with harsh cleaning agents or solvents. Refer to the
Cisco ONS 15454 Troubleshooting Guide for information about cleaning and mainta ining the fan-tray
air filter.
1.14.5 Pilot Fuse
The Pilot Fuse in the Fan tray assembly allows you to blow a low rate fuse when the main fuse of the
lower power battery is not installed in the equipment.
CC-FTAs 15454-CC-FTA 800-27558-01 and 15454-CC-FTA 800-27561-01 can automatically generate
an electrical pulse (without external commands) at power on and a bout every 25-35 minutes in order to
drain extra current from both the batteries. The am ount of current and the duration of the pulse th at the
CC-FTA can generate, is suitable to blow the fuses listed in the Table 1-28. Similar to CC-FTA,
15454-FTA3-T 800-23907-01 and 800-23907-05 can also operate the pilot fuses mentio ned in
Table 1-28 when the main fuse is missing. Unlike CC-FTA, FTA3-T alternatively drains the current from
the two batteries every 50-100 msec to feed the fans.
Table 1-28 Pilot Fuse Ratings
This is accomplished in the I-temp range (-40°C to +65°C) in either of these conditions:
• When the lower power battery is in the 43.0V to 60.0V range and the higher power battery is more
than 1V greater than the lower power battery (or)
• When the lower power battery is in the 40.0V to 60.0V range and the difference between the two
batteries does not exceed 0.5V.
1.15 Power and Ground Description
Ground the equipment according to Telcordia standards or local practices.
Cisco recommends the following wiring conventions, but customer conventions prevail:
• Red wire for battery connections (–48 VDC)
• Black wire for battery return connections (0 VDC)
• The battery return connection is treated as DC-I, as defined in GR-1089-CORE, issue 3.
Type of Fuse Current rating
Bussmann GMT-18/100A 18/100A
Bussmann GMT-1/4A 1/4A
Bussmann 70E 18/100A
Bussmann 70F 1/4A