TX Matrix Plus Cooling System Overview
Cooling System Description
The cooling system components work together to keep all TX Matrix Plus components within the acceptable temperature range (see Figure 1).
To function properly, the entire cooling system requires an unobstructed airflow and proper clearance around the site. Figure 1 shows the airflow through the router.
Figure 1: Airflow Through the TX Matrix Plus Chassis

The cooling system consists of the following components:
- Two front fan trays
- Three front air filters
- Four rear fan trays
Fan Trays
The TX Matrix Plus router contains two front fan trays and four rear fan trays. The fan trays are hot-insertable and hot-removable. In addition, each power supply has two fans that cools that power supply.
Each fan tray contains multiple fans that work in unison to cool the TX Matrix Plus components. When the router is operating normally, the fans function at lower than full speed. If a fan fails or the ambient temperature rises above a threshold, the speed of the remaining fans is automatically adjusted to keep the temperature within the acceptable range and to maintain proper cooling. If the ambient maximum temperature specification is exceeded and the system cannot be adequately cooled, the Routing Engine shuts down some or all of the hardware components. A red alarm is triggered when a fan fails, and a yellow alarm is triggered when a fan tray is removed.
The front fan trays, installed horizontally in the front of the chassis, cool the components installed in the front card cage (the TXP-F2 SIBs, TXP-CIPs, TXP-CBs, and Routing Engines). Each front fan tray contains six fans. The two front fan trays are interchangeable with each other, but are not interchangeable with the front fan trays.
![]() | Caution: The two front fan trays work as a pair. To avoid damage to the router, do not remove more than one of the two front fan trays at a time. If you remove both front fan trays, the router might shut down. |
The rear fan trays install vertically in the rear of the chassis, and cool the components installed in the rear card cage (TXP-F13 SIBs). Each rear fan tray contains nine fans (shown in Figure 2). The four rear fan trays are interchangeable with each other.
Figure 2: TX Matrix Plus Rear Fan Tray

![]() | Caution: The upper rear fan trays 2 and 4 work as a pair, and the lower rear fan trays 3 and 5 work as a pair. For each fan tray pair, only one fan tray can be removed at a time. The router might shut down if you remove both fan trays in a pair. |
Air Filters
Air filters help keep dust and other particles from entering the cooling system. The TX Matrix Plus router has three air filters located in the front of the chassis. Two air filters are located to the left of the TXP-F2S SIBs. The third air filter is located below the lower front fan tray. The left air filters are interchangeable with each other; the lower air filter is not interchangeable with the left air filters. The air filters are hot-insertable and hot-removable.

