PTX10008 Cooling System

Fan Trays

Both fan tray models contain 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 FRU side of the chassis. Two handles on each front faceplate facilitate handling of the fan tray. See Figure 1 and Figure 2.

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

Table 1: Fan Tray Specifications

Specification	JNP10008-FAN	JNP10008-FAN2
Corresponding fan tray controller model	JNP10008-FAN-CTLR	JNP10008-FTC2
Number of fans per fan tray	11	22
Number of fans per chassis	22	44
Fan numbering	0 through 10	0 through 21
Volume flow per fan tray at 100% at 72° F	720 cubic feet per minute (CFM)	920 CFM
Volume flow per chassis at 100% at 72° F	1580 CFM	2050 CFM
Switch fabric compatibility	JNP10008-SF	JNP10008-SF or JNP10008-SF3
Introduced in Junos OS Release	15.1X53-D30	19.2R1-S1
Height	22.4 in. (56.9 cm)	22.4 in. (56.9 cm)
Width	6.6 in. (16.8 cm)	6.6 in. (16.8 cm)
Depth	4.0 in. (10.2 cm) without handles, 5.2 in. (13.2 cm) with handles	5.5 in. (13.97 cm) without handles, 6.7 in. (17.01 cm) with handles
Weight	11.8 lb (5.4 kg)	20 lb (9.07 kg)

The array of fans in both models operate as a single unit. If an individual fan in the array fails, the entire fan tray must be replaced.

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 a thermal alarm, do not remove both fan trays while the router is operating.

CAUTION:

The chassis will shut down if a thermal alarm is raised for more than three minutes.

The internal fan control board in each fan tray contains the LEDs for the associated fan tray controllers and the LEDs for the three SIBs directly behind the fan tray.

Fan Tray Controllers

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

There are two fan tray controller models:

• JNP10008-FAN-CTRL—Supports model JNP10008-FAN; see Figure 3.

  Figure 3: Fan Tray Controller JNP10008-FAN-CTRL

• JNP10008-FTC2—Supports model JNP10008-FAN2; see Figure 4.

  Figure 4: Fan Controller JNP10008-FTC2

Warning:

Do not mix the fan tray controller models. Use only the supported fan tray model for each fan tray controller. See Table 2.

Table 2: Fan Tray Controller Specifications

Specification	JNP10008-FAN-CTRL	JNP10008-FTC2
Corresponding fan tray model	JNP10008-FAN	JNP10008-FAN2
Switch fabric compatibility	JNP10008-SF	JNP10008-SF or JNP10008-SF3
Introduced in Junos OS Release	15.1X53-D30	19.2R1
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	9.3 in. (23.62 cm)	9.4 in. (23.88 cm)
Weight	1.5 lb (0.68 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 software 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 (such as when a SIB is being replaced), the other fan tray controller sets the fans to full speed. This allows 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. The following examples of the show chassis fan command show the fan status for a system running JNP10008-FAN and JNP10008-FAN-CTRL:

1. This example shows the output from a JNP10008-SF fabric system running JNP10008-FAN and JNP10008-FAN-CTRL and standard Junos OS.

2. This example shows the output from a JNP10008-SF3 fabric system running JNP10008-FAN2 and JNP10008-FTC2 and standard Junos OS.

3. This example shows the output from a JNP10008-SF3 fabric system running JNP10008-FAN2 and JNP10008-FTC2 and Junos OS Evolved.

Airflow Direction in the PTX10008

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 RCBs and line cards, through the Switch Interface Boards (SIBs), 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 fan 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. See PTX10008 Fan Tray LEDs and Fan Tray Controller LEDs.

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, there is an internal fan in each power supply that also helps to cool components, such as the line cards.

Fan Tray LEDs

Each fan tray has a set of LEDs that represent the status of the fans in the fan tray, the fan tray controller, and the three Switch Interface Boards (SIBs). The fan tray LEDs are located in the top left corner of each fan tray. Figure 6 shows the location of the LEDs on JNP10008-FAN fan trays. See Figure 7 for the location of LEDs on the JNP10008-FAN2 fan trays.

Table 3 describes the functions of the fan tray LEDs.

Table 3: Fan Tray LEDs on a PTX10008 Router

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.
	Yellow	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.
	None	Off	The fan is not receiving power from the fan tray controller.
FTC (fan tray controller status)	Green	On steadily	The fan tray controller is online and is operating normally.
	Yellow	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 SIBs. 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.
SIB Status (SIB 0 status)	Green	On steadily	The left-most SIB in the chassis is online.
	Yellow	Blinking	An error has been detected in SIB 0. Replace the SIB as soon as possible. The SIB is located behind the left fan tray and is the left-most SIB 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 SIB.
	None	Off	The SIB is offline.
SIB Status (SIB 1 status)	Green	On steadily	The center SIB behind the left fan tray is online.
	Yellow	Blinking	An error has been detected in SIB 1. Replace the SIB as soon as possible. The SIB is located behind the left fan tray and is the middle SIB 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 SIB.
	None	Off	The SIB is offline.
SIB Status (SIB 2 status)	Green	On steadily	The right-most SIB behind the left fan tray is online.
	Yellow	Blinking	An error has been detected in SIB 2. Replace the SIB as soon as possible. The SIB is located behind the left fan tray and is the right-most SIB 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 SIB.
	None	Off	The SIB is offline.
SIB Status (SIB 3 status)	Green	On steadily	The left-most SIB behind the right fan tray is online.
	Yellow	Blinking	An error has been detected in SIB 3. Replace the SIB as soon as possible. The SIB is located behind the right fan tray and is the left-most SIB 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 SIB.
	None	Off	The SIB is offline.
SIB Status (SIB 4 status)	Green	On steadily	The center SIB behind the right fan tray is online.
	Yellow	Blinking	An error has been detected in SIB 4. Replace the SIB as soon as possible. The SIB is located behind the right fan tray and is the middle SIB 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 SIB.
	None	Off	The SIB is offline.
SIB Status (SIB 5 status)	Green	On steadily	The right-most SIB behind the right fan tray is online.
	Yellow	Blinking	An error has been detected in SIB 5. Replace the SIB as soon as possible. The SIB is located behind the right fan tray and is the right-most SIB 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 SIB.
	None	Off	The SIB is offline.

Fan Tray Controller LEDs

All models of fan tray controller have the same 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 JNP10008-FAN-CTRL or the JNP10008-FTC2 fan tray controller faceplate.

Table 4 describes the functions of the fan tray controller LEDs.

Table 4: Fan Tray Controller LEDs on a PTX10008

Name	Color	State	Description
PWR (fan tray controller power)	Green	On steadily	The fan tray controller has power and is operating normally.
	Yellow	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.
	Yellow	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.