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Installing a Power Supply in a QFX3500 Device

  • Before you install a power supply in a QFX3500 device, ensure that you have taken the necessary precautions to prevent electrostatic discharge (ESD) damage (see Prevention of Electrostatic Discharge Damage).

  • Ensure that the airflow direction of the power supply is the same as the chassis. Labels on the power supply handle indicate the direction of airflow. See Cooling System and Airflow for a QFX3500 Device for more information.

  • Ensure that you have the following parts and tools available to install a power supply in a QFX3500 device:

    • ESD grounding strap

The QFX3500 is shipped from the factory with two 650 W power supplies pre-installed. Each power supply is a hot-removable and hot-insertable field-replaceable unit (FRU) when the second power supply is installed and running. You can install replacement power supplies without powering off the device or disrupting the switching function.

To install a power supply in a QFX3500 device (see Figure 1):

  1. Attach the ESD grounding strap to your bare wrist, and connect the strap to the ESD point on the chassis.
  2. Taking care not to touch power supply components, pins, leads, or solder connections, remove the power supply from its bag.

    Verify that the direction of the arrow on the power supply handle matches the direction of airflow in the chassis. Ensure that each power supply you install in the chassis has the same airflow direction. If you install power supplies with two different airflow directions, Junos OS raises an alarm, and the status (OK/!) LED blinks amber.

  3. Using both hands, place the power supply in the power supply slot on the front panel of the device and slide it in until it is fully seated and the locking lever slides into place.
Figure 1: Installing a Power Supply in a QFX3500 DeviceInstalling a Power Supply in a QFX3500 Device

Each power supply must be connected to a dedicated power source outlet.


If you have a Juniper Care service contract, register any addition, change, or upgrade of hardware components at . Failure to do so can result in significant delays if you need replacement parts. This note does not apply if you replace existing components with the same type of component.