Replacing an M320 Fan Tray

Removing an M320 Front Fan Tray

The router has two front fan trays. The front fan trays install horizontally in the front of the chassis. Each front fan tray contains four fans. The two front fan trays are interchangeable, but the rear fan tray is not interchangeable with the front fan trays. The fan trays are hot-insertable and hot-removable.

The upper front fan tray is located above the FPC card cage, and the lower front fan tray is located below the front air filter. Each fan tray weighs about 11 lb (5.1 kg).

To remove a front fan tray (see Figure 1):

1. Attach an electrostatic discharge (ESD) grounding strap to your bare wrist, and connect the strap to one of the ESD points on the chassis.
2. If you are removing the lower fan tray, perform the following steps:
   1. Unwrap any PIC cables from the spools on the cable management system and remove the cables from the tray. Arrange the cables so that they do not block the front of the cable management system and tray, and secure them with temporary fasteners so that they are not supporting their own weight as they hang from the connector.

      Caution: Do not let fiber-optic cable hang free from the connector. Do not allow fastened loops of cable to dangle, which stresses the cable at the fastening point.

   2. Simultaneously pull the two releases labeled PULL on the cable management system. Lift it up and outward to lock it in place to access the lower fan tray.
3. Loosen the captive screw on each side of the fan tray faceplate.
4. Grasp the handles and pull the fan tray until it stops.

   Warning: To avoid injury, keep tools and your fingers away from the fans as you slide the fan tray out of the chassis. The fans might still be spinning.

5. Press the tabs on both sides of the fan tray and pull the fan tray halfway out of the chassis.
6. When the fans stop spinning, place one hand under the fan tray to support it, and pull the fan tray completely out of the chassis.

Figure 1: Removing a Front Fan Tray

Installing an M320 Front Fan Tray

To install a front fan tray (see Figure 2):

1. Attach an electrostatic discharge (ESD) grounding strap to your bare wrist, and connect the strap to one of the ESD points on the chassis.
2. Grasp the fan tray by its handles and insert it straight into the chassis.
3. Tighten the captive screws on each side of the fan tray faceplate to secure it in the chassis.
4. If you are installing the lower fan tray, follow these steps:
   1. Unlock the cable management system and lower it to the fully lowered position.
   2. Rearrange the PIC cables in the cable management system. For more information about proper cable arrangement, see Maintaining M320 PICs and PIC Cables.

Figure 2: Installing a Front Fan Tray

Removing an M320 Rear Fan Tray

The rear fan tray is mounted vertically on the right side of the rear of the chassis. The rear fan tray contains seven fans. The fan tray weighs about 8.4 lb (3.8 kg).

Caution: To maintain proper cooling, do not operate the router with the rear fan tray removed for more than 1 minute.

To remove the rear fan tray (see Figure 3):

1. Attach an electrostatic discharge (ESD) grounding strap to your bare wrist, and connect the strap to one of the ESD points on the chassis.
2. Loosen the captive screws on the top and bottom of the fan tray faceplate, using a Phillips (+) screwdriver, number 2.
3. Grasp the handle and pull the fan tray halfway out of the chassis.

   Warning: To avoid injury, keep tools and your fingers away from the fans as you slide the fan tray out of the chassis. The fans might still be spinning.

4. When the fans stop spinning, place one hand under the fan tray to support it, and pull the fan tray completely out of the chassis.

Figure 3: Removing the Rear Fan Tray

Installing an M320 Rear Fan Tray

To install a replacement rear fan tray (see Figure 4):

1. Attach an electrostatic discharge (ESD) grounding strap to your bare wrist, and connect the strap to one of the ESD points on the chassis.
2. Grasp the handle with one hand and place the other hand under the fan tray. Insert the fan tray straight into the chassis.
3. Tighten the captive screws on the fan tray faceplate to secure it in the chassis, using a Phillips (+) screwdriver, number 2.

Figure 4: Installing a Rear Fan Tray