Help us improve your experience.

Let us know what you think.

Do you have time for a two-minute survey?


Connecting AC Power to a QFX5110

Ensure that you have a power cord appropriate for your geographical location available to connect AC power to the switch.

Before you begin connecting AC power to the switch:

  • Ensure that you have taken the necessary precautions to prevent electrostatic discharge (ESD) damage (see Prevention of Electrostatic Discharge Damage).

  • Ensure that you have connected the switch chassis to earth ground.


    Before you connect power to the switch, a licensed electrician must attach a cable lug to the grounding and power cables that you supply. A cable with an incorrectly attached lug can damage the switch (for example, by causing a short circuit).

    To meet safety and electromagnetic interference (EMI) requirements and to ensure proper operation, you must connect the chassis to earth ground before you connect it to power. For installations that require a separate grounding conductor to the chassis, use the protective earthing terminal on the switch chassis to connect to the earth ground. For instructions on connecting earth ground, see Connect the QFX5110 to Earth Ground.

    On AC systems, the switch gains additional grounding when you plug the power supply in the switch into a grounded AC power outlet by using the AC power cord appropriate for your geographical location (see QFX5110 AC Power Supply Description).

  • Install the power supply in the chassis. For instructions on installing a power supply in a QFX5110, see Installing a Power Supply in a QFX5110.

The QFX5110 is shipped 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 in the two slots next to the fan modules without powering off the switch or disrupting switch functions.


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

To connect AC power to a QFX5110:

  1. Attach the grounding strap to your bare wrist and to a site ESD point.
  2. Ensure that the power supplies are fully inserted in the chassis and the latches are secure. If only one power supply is installed, ensure that a blank cover panel is installed over the second power supply slot.
  3. Locate the power cord or cords shipped with the switch; the cords have plugs appropriate for your geographical location. See QFX5110 AC Power Specifications.

    Ensure that the power cord does not block access to device components or drape where people can trip on it.

  4. Connect each power supply to the power sources. Insert the coupler end of the power cord into the AC power cord inlet on the AC power supply faceplate.
  5. Push the power cord retainer onto the power cord (see Figure 1).
    Figure 1: Connecting an AC Power Cord to an AC Power Supply in a QFX5110Connecting an AC Power Cord to an AC Power Supply in a QFX5110
    Power cord retainer
  6. If the AC power source outlet has a power switch, set it to the off (O) position.

    The switch powers on as soon as power is provided to the power supply. There is no power switch on the device.

  7. Insert the power cord plug into an AC power source outlet.
  8. If the AC power source outlet has a power switch, set it to the on (|) position.
  9. Verify that the AC and DC LEDs on each power supply are lit green.

    If the amber fault LED is lit, remove power from the power supply, and replace the power supply (see Removing a Fan Module from a QFX5110). Do not remove the power supply until you have a replacement power supply ready: the power supplies or a blank cover panel must be installed in the switch to ensure proper airflow.


    Replace a failed power supply with a blank panel or new power supply within one minute of removal to prevent chassis overheating.