Powering the Modular Switch

Important:

Installation of this equipment must comply with local and national electrical codes. Consult with the appropriate regulatory agencies and inspection authorities to ensure compliance if necessary.

 

L'installation de cet équipement doit être conforme aux codes électriques locaux et nationaux. Consultez les agences de réglementation et les autorités d'inspection appropriées pour garantir la conformité si nécessaire.

 

 

Note: Arista modular switches take 15 to 30 minutes to boot completely.

 

The switch operates with multiple power supplies. Refer to Table 1 for information regarding your specific system. Table 2, and Table 3 list the quantities of modules each chassis can contain and the minimum operating requirements for each model.

 

Table 1. Power Supply Capacity and Requirements for DCS-7358X4, DCS-7368X4, and DCS-7289R3A Series Modular Switches
Switch Model Chassis Capacity (Power Supply Units) Minimum Operating Requirements (non-redundant power)
DCS-7358X4 4 1 active circuit
DCS-7368X4 4 1 active circuit
DCS-7289R3A(1) 4 1 active circuit

(1): Some configurations could require more than one active circuit.

 

 

Rear Panels displays the location of the power supplies on the switch.

This chapter includes sections that describe the procedure for grounding and cabling power supplies. After completing the instructions for your switch, proceed to Connecting Serial and Management Cables.

 

Important:

Read all installation instructions before connecting the system to the power source.

 

Lire toutes les instructions d'installation avant de brancher le système à la source d'alimentation.

 

  • Non-Redundant Configuration: Provide power to the minimum required power inputs.
  • Redundant Power Supply Configuration: Connecting power to modules over minimum requirements protects the switch against failed modules and can provide grid-level redundancy.
  • Power down the Switch: Remove all power cords from the power input sockets.

 

Important:

This equipment must be grounded. Never defeat the ground conductor. This unit requires over-current protection.

 

Cet équipement doit être mis à la terre. Ne jamais modifier le conducteur de terre. Cet appareil nécessite de protection contre les surintensités.

 

Cabling the AC Power Supply

Grounding the Switch

After mounting the switch into the rack, connect the switch to the data center ground. The grounding pads are located on the rear of the switch. It would help if you used a right-angle ground lug to attach the chassis ground wire and route it to the data center ground, as shown in the following figure.

 

Figure 1. Grounding the Switch

 

Important:

Grounding wires and grounding lugs (M4 x 0.7) are not supplied. Wire size should meet local and national installation requirements. Commercially available 6 AWG wire is recommended for installations in the U.S.

 

À la terre et de mise à la terre fils cosses (M4 x 0.7) ne sont pas fournis. Calibre des fils doit satisfaire des exigences de l’installation locale et nationale. Disponible dans le commerce des câbles 6 AWG sont recommandé pour les installations aux États-Unis.

 

After the switch is grounded, ESD wrist straps can be grounded by connecting them to the ESD port on either the rear or the front of the switch, as shown in the following figures.

 

Figure 2. ESD Sockets (Rear)



1 Switch Card Module Release Handle 6 PSU Status LED
2 Fan 7 PSU
3 Fan Release Handle 8 PSU Release Handle
4 Fan Installation Indicator 9 Ground
5 Fan Status LED 10 ESD

 

 

Figure 3. ESD Sockets (Front)

1 Supervisor Module 3 Linecard Ejector Latch
2 Supervisor Ejector Latch 4 ESD

 

Connecting the Power Cables to an AC Power Supply

The following figure displays an AC power supply module, including the power input socket.

 

Figure 4. AC Power Supply

1 Power Supply Status LED

 

The power supplies require power cables that comply with an IEC-320 C19 plug. The accessory kit provides 14 AWG, C19, to C20 power cables.

To insert a power cable:

  1. Pull the retaining clip back on each power input socket.

     

    Note: The retaining clip is optional (if provided).

     

  2. Plug the power cables into the sockets.
  3. Adjust the retaining clips for your power cords (if a retaining clip was provided).
  4. Push the retaining clip back down over the cable (if a retaining clip was provided).
     

DC Power Supplies

The following figure displays a DC power supply module.

Figure 5. DC Power Supply


 

Important:

A disconnect device must be provided as part of the installation.

 

Un dispositif de sectionnement doit être fourni dans le cadre de l'installation.

 

Important:

Ensure power is removed from DC circuits before performing any installation actions. Locate the disconnect device, circuit breakers, or fuses on DC power lines servicing the circuits. Turn off the power line circuits or remove the fuses.

 

Pouvoir assurer qu'il est retiré de circuits DC avant d'effectuer des actions d'installation . Localiser les disjoncteurs ou des fusibles sur les lignes de courant continu desservant les circuits. Coupez les circuits de lignes d'alimentation ou retirer les fusibles.

 

Important:

Wire size must comply with local and national requirements and electrical codes. Use only copper wire.

 

Le calibre du fil doit être conforme aux exigences locales et nationales et les codes électriques. Utiliser du fil de cuivre.

 

Important:

Apply ground connection to the switch first during installation and remove last when removing power.

 

Appliquer connexion à la terre à l'interrupteur premier lors de l'installation et de supprimer la dernière alimentation lors du débranchement.

 

Wire and Lug Preparation

Before installing, remove power from DC circuits by turning off the power line servicing the circuits. Prepare the stranded wiring before you begin a DC power installation.

 

Note: Stranded copper wiring is required and should meet local and national installation requirements. Wires and grounding lugs are not supplied.

 

  1. Attach an ESD grounding strap.
  2. Prepare the stranded copper wiring for the power supply to be used. The following table provides wiring, lug, and tightening torque information for the power supplies covered in this guide.

     

    Table 2. Wiring, Lug, and Tightening Torques for DC PSUs
    PSU Wire Size (1) Lug Type (2) Tightening Torque
    (AWG) (mm 2 ) N • m in. • lbs.
    PWR-1900-DC 4 - 6 21.2 - 13.3 dual-hole 2.7 24

    1 Unless otherwise noted, wire size applies to -48V, Battery return, and Protective earth wires.

    2 Unless otherwise noted, twin #10 studs spaced for dual-hole lug with 5/8" hole spacing.

     

     

  3. Strip the wires to the appropriate length for the lugs to be used.
  4. Select agency-approved compression (pressure) lugs for wiring terminations.
  5. Slip on heat-shrink tubing on the wire ends before assembling the lugs onto the wire.
  6. Crimp the lugs with the proper tool, and ensure that the tubing extends over the barrel of the lugs and the insulation on the wires. The following figure shows an example lug.

     

    Figure 6. Lug Preparation

    1 Insulated wire A 1/4”
    2 Heat-shrink tubing B 1/2”
    3 Lug C 5/8”
     
  7. Shrink the tubing with a heat gun.
     

Connecting a DC Power Supply to Power Source

To connect a DC power supply to a power source, perform the following:
  1. Prepare the stranded wiring (Wire and Lug Preparation).
  2. Attach the appropriate lugs to the source DC wires.
  3. Connect the DC-input wires to the appropriate terminals using the specified torque (Table 2) in the following order.

     

    Note: Remove terminal covers as needed.

     

    1. Ground wire to the Protective Earth (PE ) terminal.
    2. Negative source DC cable to the negative (- / -48V) terminal.
    3. Positive (+) source DC cable to the positive (+ / Rtn) terminal.

       

  4. Replace the terminal covers as required.

     

    Figure 7. DC PSU Connection Example