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):

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 https://www.juniper.net/customers/support/tools/updateinstallbase/ . 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.