MX10004 Cooling System

Fan Tray

The JNP10004-FAN3 fan tray contains an array of six fans modules, each with two counter-rotating fans. JNP10004-FAN3 fan tray operates as a single hot-removable and hot-insertable field-replaceable unit (FRU). The fan trays are installed vertically, side by side, next to the power supplies on the rear of the chassis and provide front-to-back chassis cooling. You can remove or insert the fan trays by using the two handles provided on the face plate, See Figure 1 and Figure 3.

The JNP10004-FAN2 fan tray contains an array of internal fans, a non-removable control board, and LEDs.

The two fan trays install vertically, side by side, next to the power supplies on the rear side of the chassis. Two handles on each front faceplate facilitate handling of the fan tray. See Figure 2 and Figure 3.

See Table 1 for the physical specifications of the fan trays.

Table 1: Fan Tray Specifications

Specification	JNP10004-FAN3	JNP10004-FAN2
Corresponding fan tray controller model	JNP10004-FTC3	JNP10004-FTC2
Number of fan modules per fan tray	6	6
Number of fan modules per chassis	12	12
Fan numbering	0 through 11	0 through 11
Volume flow at 100 percent	1100 CFM for both fan trays (550 CFM per tray)	948 CFM for both fan trays
Height	12.09 in. (30.7 cm)	12.08 in. (30.68 cm)
Width	6.6 in. (16.8 cm)	6.6 in. (16.8 cm)
Depth	5.88 in. (14.94 cm) without handles	5.5 in. (13.97 cm) without handles, 6.85 in. (17.4 cm) with handles
Weight	14.4 lb (6.53 kg)	9.8 lb (4.45 kg)

The fan tray operates as a single unit. If an individual fan in the tray fails, you must replace the entire fan tray. However, the fan tray continues to operate indefinitely and provides sufficient cooling even when a single fan rotor fails. The fan tray operates indefinitely provided that the room temperature is within the operating range.

If you want to replace an existing fan tray while the router is running, remove only one fan tray. The router continues to operate for a limited time with a single operating fan tray without triggering a thermal alarm.

CAUTION:

To avoid triggering a thermal alarm, remove only one fan tray while the router is operating.

Fan Tray Controller

The MX10004 supports two fan tray controllers to provide the control logic and power to hot-insert and hot-remove a fan tray

• JNP10004-FTC2—Supports model JNP10004-FAN2 fan tray; see .

• JNP10004-FTC3—Supports JNP10004-FAN3 fan tray and JNP10004-FAN2 fan trays; see Figure 4.

  Table 2: Fan Tray Controller - Fan Tray Compatability

  Fan Tray Controller	Compatible Fan Tray
  JNP10004-FTC2	JNP10004-FAN2
  JNP10004-FTC3	JNP10004-FAN3, JNP10004-FAN2

  Warning:

  Do not mix the fan tray controller models. Use only the supported fan tray model for each fan tray controller. See Table 3.

  Do not use JNP10004-FTC2 with JNP10004-FAN3 fan tray.

  Figure 4: Fan Tray Controller JNP10004-FTC2 or JNP10004-FTC3

Table 3: Fan Tray Controller Specifications

Specification	JNP10004-FTC3	JNP10004-FTC2
Corresponding fan tray model	JNP10004-FAN3	JNP10004-FAN2
Height	1.5 in. (3.81 cm)	1.5 in. (3.81 cm)
Width	6.5 in. (15.24 cm)	6.5 in. (15.24 cm)
Depth	12.4 in. (31.5 cm)	12.4 in. (31.5 cm)
Weight	1.1 lb (0.5 kg)	1.1 lb (0.5 kg)

The system continually monitors the temperature of critical parts across the chassis and adjusts the chassis fan speed according to the temperature. Junos OS controls the fan speed. Under normal operating conditions, the fans in the fan tray run at less than full speed. If one fan tray controller fails or appears missing , the other fan tray controller sets the fans to full speed. (A fan tray can appear to be missing when you replace an SFB, for example.) The ability to modify fan speed enables the router to continue to operate normally as long as the remaining fans cool the chassis sufficiently. Use the show chassis fan command to see the status of individual fans and fan speed.

To determine the cooling of all the components in the system, use the show chassis environment command.

Airflow Direction in the MX10004

The air intake to cool the chassis is located on the port (line card) side of the chassis. Air flows into the chassis from the ports in the Routing and Control Boards (RCBs) and line cards, through the Switch Fabric Boards (SFBs), and exits from the fan trays and the power supplies. See Figure 5.

The fan tray continues to operate indefinitely and provide sufficient cooling even when a single rotor fails, provided the room temperature is within the operating range. You can check the status of fans by viewing the LEDs on each fan tray.

You cannot replace a single fan. If one or more fans fail, you must replace the entire fan tray.

In addition to the fans in the fan trays, an internal fan in each power supply also helps to cool components such as line cards.

Fan Tray LEDs

Each fan tray has a set of five LEDs that represent the status of the fans in the fan tray, the fan tray controller, and three of the Switch Fabric Boards (SFBs) that are installed behind the fan tray. The LEDs are located on the top left corner of each fan tray. Figure 6 shows the location of the LEDs on JNP10004-FAN2 and JNP10004-FAN3 fan trays.

Table 4 describes the functions of the fan tray LEDs.

Table 4: Fan Tray LEDs on an MX10004

Name	Color	State	Description
FAN (fan status)	Green	On steadily	All fans are operating normally. The system has verified that the fan tray is engaged, that the airflow is in the correct direction, and that all fans are operating correctly.
	Green	Blinking	The fan tray is starting. The fan tray is not ready.
	Amber	Blinking	An error has been detected in one or more fans in the fan tray. Replace the fan tray as soon as possible. Either the fan has failed or it has become disconnected. To maintain proper airflow through the chassis, leave the fan tray installed in the chassis until you are ready to replace it.
	Amber	Blinking	Beacon is enabled.
	None	Off	The fan is not receiving power from the fan tray controller. All fans are off.
FTC (fan tray controller status)	Green	On steadily	Power is on. The fan tray controller is online and is operating normally.
	Amber	Blinking	An error has been detected in the fan tray controller. Replace the fan tray controller as soon as possible. The fan tray controller is located behind the fan tray above the SFBs. To maintain proper airflow through the chassis, leave the fan tray installed in the chassis until you are ready to replace the fan tray controller.
	Amber	Blipping	Beacon is enabled.
	None	Off	The fan tray controller is not receiving power.
SIB Status (SFB 0 status)	Green	On steadily	The left-most SFB in the chassis is online.
	Amber	Blinking	An error has been detected in SFB 0. Replace the SFB as soon as possible. The SFB is located behind the left fan tray and is the left-most SFB in the chassis. To maintain proper airflow through the chassis, leave the fan tray installed in the chassis until you are ready to replace the SFB.
	Amber	Blipping	Beacon is enabled.
	None	Off	The SFB is offline.
SIB Status (SFB 1 status)	Green	On steadily	The center SFB behind the left fan tray is online.
	Amber	Blinking	An error has been detected in SFB 1. Replace the SFB as soon as possible. The SFB is located behind the left fan tray and is the middle SFB in the group of 3. To maintain proper airflow through the chassis, leave the fan tray installed in the chassis until you are ready to replace the SFB.
	None	Off	The SFB is offline.
SIB Status (SFB 2 status)	Green	On steadily	The right-most SFB behind the left fan tray is online.
	Amber	Blinking	An error has been detected in SFB 2. Replace the SFB as soon as possible. The SFB is located behind the left fan tray and is the right-most SFB in the group of 3. To maintain proper airflow through the chassis, leave the fan tray installed in the chassis until you are ready to replace the SFB.
	Amber	Blipping	Beacon is enabled.
	None	Off	The SFB is offline.
SIB Status (SFB 3 status)	Green	On steadily	The left-most SFB behind the right fan tray is online.
	Amber	Blinking	An error has been detected in SFB 3. Replace the SFB as soon as possible. The SFB is located behind the right fan tray and is the left-most SFB of the group of 3. To maintain proper airflow through the chassis, leave the fan tray installed in the chassis until you are ready to replace the SFB.
	Amber	Blipping	Beacon is enabled.
	None	Off	The SFB is offline.
SIB Status (SFB 4 status)	Green	On steadily	The center SFB behind the right fan tray is online.
	Amber	Blinking	An error has been detected in SFB 4. Replace the SFB as soon as possible. The SFB is located behind the right fan tray and is the middle SFB in the group of 3. To maintain proper airflow through the chassis, leave the fan tray installed in the chassis until you are ready to replace the SFB.
	Amber	Blipping	Beacon is enabled.
	None	Off	The SFB is offline.
SIB Status (SFB 5 status)	Green	On steadily	The right-most SFB behind the right fan tray is online.
	Amber	Blinking	An error has been detected in SFB 5. Replace the SFB as soon as possible. The SFB is located behind the right fan tray and is the right-most SFB in the group of 3. To maintain proper airflow through the chassis, leave the fan tray installed in the chassis until you are ready to replace the SFB.
	Amber	Blipping	Beacon is enabled.
	None	Off	The SFB is offline.

Fan Tray Controller LEDs

The fan tray controller LEDs are visible only when the associated fan tray is removed. The fan tray controller LEDs are located on the right of the controller panel. Figure 8 shows the location of the LEDs on the JNP10004-FTC2 fan tray controller faceplate.

Table 5 describes the functions of the fan tray controller LEDs.

Table 5: Fan Tray Controller LEDs on an MX10004

Name	Color	State	Description
PWR (fan tray controller power)	Green	On steadily	The fan tray controller has power and is operating normally.
	Amber	Blinking	A power error has been detected in the fan tray controller. Replace the fan tray controller as soon as possible. To maintain proper airflow through the chassis, leave the fan tray installed in the chassis until you are ready to replace the fan tray controller.
	None	Off	The fan tray controller is not powered on or is not receiving power.
STATUS (fan tray controller status)	Green	On steadily	The fan tray controller is online and is operating normally.
	Amber	Blinking	An error has been detected in the fan tray controller. Replace the fan tray controller as soon as possible. To maintain proper airflow through the chassis, leave the fan tray installed in the chassis until you are ready to replace the fan tray controller.
	None	Off	The fan tray controller is not receiving power.