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Cisco ONS 15310-MA SDH Reference Manual, Release 9.1 and Release 9.2
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Chapter 1 Cisco ONS 15310-MA SDH Shelf Assembly Hardware
Fan-Tray Assembly
every 15 minutes (at 24 degrees Celsius or 120 degrees Fahrenheit), alternating between power supply
inputs A and B. This allows the ONS 15310-MA SDH to blow the low current fuse when there is a failure
or loss of the main fuse and report an alarm (FAN alarm).
The front of the fan-tray assembly has CRIT, MAJ, and MIN alarm LEDs that illuminate if a Critical,
Major, or Minor alarm is present anywhere on the ONS 15310-MA SDH assembly.
1.10.1 Fan Speed and Power RequirementsFan speed is controlled by temperature sensors on the 15310E-CTX-K9 card. The sensors measure the
input air temperature at the fan-tray assembly. Fan speed options are low, medium, and high.
1.10.2 Fan FailureIf one or more fans fail on the fan-tray assembly, replace the entire assembly. You cannot replace
individual fans. The red Fan Fail LED on the front of the fan tray illuminates when one or more fans fail.
For fan-tray replacement instructions, refer to the Cisco ONS 15310-MA SDH Troubleshooting Guide.
The red Fan Fail LED is unlit after you install a working fan tray.
Note The red Fan Fail LED on the front of the fan tray illuminates when only one power source is connected
to the chassis, or any fuse blows.
1.10.3 Air Filter The ONS 15310-MA SDH contains a reusable air filter (15310-MA SDH-FTF) that is installed above
the fan-tray assembly. The reusable filter is made of a gray, open-cell, polyurethane foam that is specially
coated to provide fire and fungi resistance. Spare filters should be kept in stock.
Caution Do not operate an ONS 15310-MA SDH without the mandatory fan-tray air filter.
1.10.4 OrderwireOrderwire allows a crafts person to plug a phone set into an ONS 15310-MA SDH and communicate
with crafts people working at other ONS 15310-MA SDH nodes or other facility equipment. The
orderwire is a pulse code modulation (PCM) encoded voice channel that uses E1 or E2 bytes in the
MSOH and in the regenerator section overhead.
The FTA allows simultaneous either local (RSOH signal) or express (MSOH signal) orderwire channels
on an SDH ring or particular optics facility. Express orderwire also allows communication through
regeneration sites when the regenerator is not a Cisco device.
You can provision orderwire functions with CTC similar to the current provisioning model for DCC
channels. In CTC, you provision the orderwire communications network during ring turn-up so that all
network elements (NEs) on the ring can communicate with one another. Orderwire terminations (that is,
the optics facilities that receive and process the orderwire channels) are provisionable. Both express and
local orderwire can be configured as on or off on a particular SDH facility. The ONS 15310-MA SDH
supports up to four orderwire channel terminations per shelf. This allows linear, single ring, dual ring,