Figure 168: M320 Router Cooling System And Airflow - Juniper M Series Monitoring And Troubleshooting Manual

Hide thumbs Also See for M Series:

Table of Contents

M Series and T Series Routers Monitoring and Troubleshooting Guide

Figure 168: M320 Router Cooling System and Airflow

Documentation

T320 and T640 Router Cooling Systems

Checklist for Monitoring the Cooling System on page 317

The cooling system in the T320 and T640 routers consists of the following components:

Two front fan trays—The front fan trays each contain six fans and are interchangeable.

The fan trays in the front of the chassis, each with six fans, cool the components

installed in the FPC card cage (the FPCs, PICs, CIP, and midplane).

Rear fan tray—The rear fan tray contains five fans and is not interchangeable with the

front trays. It cools the components installed in the rear card cage (the Routing Engines,

Control Boards, PCGs, and SIBs).

Front and rear air filter—Air filters for both the front and rear fan trays help keep dust

and other particles from entering the cooling system.

Power supply fans—The power supplies each have a fan that cools that power supply.

During normal operation, the fans in each fan tray function at less than full capacity.

Temperature sensors on the midplane and the host subsystem control the speed of the

fans. A fan failure triggers the red alarm LED on the craft interface. If the temperature

passes a certain threshold, the Junos OS turns off the power supplies.

Figure 169 on page 331

shows the T320 router cooling system components.