Cabling the Modular Switch

The following topics are covered in this section:

Cabling the Power Supplies

Before you begin, refer to the Arista Networks document Compliance and Safety Guide available at: https://www.arista.com/en/support/product-documentation.

Note: Power supplies may be loaded in the PSU bays in any order. The following order is recommended for each of the switches covered by this guide.

 

Table 1. Recommended PSU Bay Population Order
Switch Order
DCS-7804 8, 7, 6, 5, 4, 3, 2, 1
DCS-7808 6, 12, 5, 11, 4, 10, 3, 9, 2, 8, 1, 7
DCS-7812 9, 18, 8, 17, 7, 16, 6, 15, 5, 14, 4, 13, 3, 12, 2, 11, 1, 10
DCS-7816 8, 16, 24, 7, 15, 23, 6, 14, 22, 5, 13, 21, 4, 12, 20, 3, 11, 19, 2, 10, 18, 1, 9, 17

 

The following figure shows the recommended order. All unpopulated bays should be covered with a blank (X).

Note: '*' designates the recommended starting bay.
Important: Power down the switch: Remove all power cords from the power inlets.

 

Mettez le commutateur: Retirez tous les cordons d'alimentation des prises d'alimentation.

 

Important: Installation of this equipment must comply with local and national electrical codes. If necessary, consult with the appropriate regulatory agencies and inspection authorities to ensure compliance.

 

Installation de cet équipement doit être conformes aux codes électriques locaux et nationaux. Si nécessaire, consulter les organismes de réglementation appropriés et des autorités de contrôle pour assurer la conformité.

 

Note: Many configurations will require additional power supplies.

 

Nombreuses configurations exigera des alimentations supplémentaires.

 

Important: All power supply slots must be filled with either a power supply or blank to ensure proper air flow.

 

Tous les emplacements d'approvisionnement de puissance doivent être remplis avec une alimentation ou vide pour assurer un débit d'air appropriée.

 

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.

 

The Table 3 shows the minimum number of operating power supplies that must be connected to active circuits for each switch to operate.

Each power supply includes a fan that maintains proper power supply temperature. The appendices display the location of components for all switches described in this guide.

Cabling Chassis Ground

The Figure 1, Figure 2, Figure 3, and Figure 4 display the location of the chassis grounding locations on the front panel of the switches. Chassis ground locations are also located on the rear panel of the switch chassis. After mounting the switch into the rack, connect at least one of the chassis grounds to the data center ground using two-hole ground lugs with 16 mm (5/8 in.) spacing, and two M4 x 0.7 screws. After the switch is grounded, ESD wrist straps can be grounded by connecting them to one of the attach points.

Important: Grounding wires and grounding lugs are not supplied. Wire size should meet local and national installation requirements. Commercially available 2 or 4 AWG wire is recommended for installations in the U.S.

 

À la terre et de mise à la terre fils cosses ne sont pas fournis. Calibre des fils doit satisfaire des exigences de l'installation locale et nationale. Disponible dans le commerce 2 ou 4 AWG fil est recommandé pour les installations aux États-Unis.

 

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.

 

Important: Secondary Grounding wires, lugs, and screws (M4 x 0.7) are not supplied.

 

Secondaire à la terre, câbles, cosses et vis (M4 x 0.7) ne sont pas fournis.

 

Figure 1. Front Panel (DCS-7804)

1 Power supplies 4 Linecards 7 Supervisor lock
2 Linecard and Supervisor extraction tool tether 5 Linecard lock 8 Grounding locations
3 Extraction tool 6 Supervisor modules 9 ESD attach point

 

Figure 2. Front Panel (DCS-7808)

1 Power supplies 4 Linecards 7 Supervisor lock
2 Linecard and Supervisor extraction tool tether 5 Linecard lock 8 Grounding locations
3 Extraction tool 6 Supervisor modules 9 ESD attach point

 

Figure 3. Front Panel (DCS-7812)

1 Power supplies 4 Linecards 7 Supervisor lock
2 Linecard and Supervisor extraction tool tether 5 Linecard lock 8 Grounding locations
3 Extraction tool 6 Supervisor modules 9 ESD attach point

 

Figure 4. Front Panel (DCS-7816)

1 Power supplies 6 Supervisor modules 11 Extraction tool
2 Linecard and Supervisor extraction tool tether 7 Supervisor lock 12 Grounding locations
3 Extraction tool 8 Linecards 13 ESD attach point
4 Linecards 9 Linecard lock    
5 Linecard lock 10 Linecard and Supervisor extraction tool tether    
Note: To power down the switch, remove all power cords from the power inlets.

Cabling the AC Power Supplies

The switches use PWR-D1-3041-AC-BLUE (Figure 5) power supplies with SAF-D-GRID connectors on the PSU inputs. Power cables are included with the accessory kit (Table 1). To power the switch, insert the other side of the cable into the main power providing circuit.

Note: The power supply, handle color, orientation, etc. may be different in your device from the one shown in Figure 5.

 

Figure 5. AC Power Supply

The Front Panel displays the front panel location of the power supplies.

Note:
  • The LEDs on a PSU remain lit for a period of time even after you disconnect the power and remove the PSU from the chassis. They will eventually turn off in a short while.
  • The PWR-D1-3041-AC-BLUE PSU uses 2x 220 V supply inputs and uses 2 APP SAF-D-GRID 400 connectors.

 

Cabling the DC Power Supply

Note: The -48V and Battery-Return leads are a pair and should run adjacent to each other and be approximately the same length.

 

Le - 48V et câbles de batterie-retour sont une paire courir à côté de l'autre et doivent être à peu près la même longueur.

 

DC Power Supplies

The switches support the PWR-D2-3041-DC-BLUE DC power supply displayed in Figure 6.

Figure 6. PWR-D2-3041-DC-BLUE Power Supplies

Note: Release lever color indicates airflow direction.

 

Wire and Lug Preparation

Before performing any installation actions, ensure power is removed from DC circuits by turning off the power line servicing the circuits. Prepare the stranded wiring before you begin a DC power installation.
  1. Stranded copper wiring is required.
    • Commercially available 1 to 2 AWG wire is recommended for installations in the U.S.
    • Wire size should meet local and national installation requirements.
    • Grounding wires and grounding lugs are not supplied.
    • Strip the wires to the appropriate length for the lugs.

    The wires connecting the DC power supply to the power source must meet the following requirements:

    • DC Input Wire Size: 1– 2 AWG
    • Primary Ground Wire Size: 1– 2 AWG per power supply.
    • The conductors are copper
  2. Use agency-approved compression (pressure) lugs for wiring terminations (2x - Two M6 studs with 5/8" spacing).
  3. Slip on heat-shrink tubing on the wire ends before assembling the lugs on to the wire.
    • The lugs must be crimped with the proper tool.
    • The tubing should extend over the lug’s barrel and the wire's insulator.
  4. Shrink the tubing with a heat gun.
    Figure 7. Lugs Wiring Terminations

    1 Insulated wire 3 Lug 5 Half-inch width
    2 Heat-shrink tubing 4 Quarter-inch diameter hole 6 Five-eighth-inch apart centers
     

Power Supply Specifications

The Table 2 shows the power supply specifications for each of the PSUs supported.

Table 2. Power Supply Specifications (each PSU)
Power Supply Maximum Output Power Rating (DC) Input Voltage and Frequency Maximum Input Current Input Branch Circuit Protection
PWR-D1-3041-AC-BLUE 3000 W 200 to 240 VAC(nominal) 50/60 Hz (nominal) 2x 16 A 2x 20 A
PWR-D2-3041-DC-BLUE 3000 W -48 V to -60 VDC, 70 A to 55A 2x 70 A 2x 90 A
Important: Each power supply requires input branch circuit protection in compliance with AHJ requirements.

 

Chaque alimentation nécessite une protection du circuit de la branche d’entrée conformément aux exigences de l’AHJ.

 

Power Supply Configurations

The Table 3 shows the power supply configurations for the modular switches.

Table 3. Power Supply Configurations
Modular Switch Recommended Number of PSUs (for redundancy) Number of PSUs Shipped in Bundle Minimum Number of PSUs Required Maximum Number of PSUs Supported
DCS-7804 6 6 6 8
DCS-7808 8 8 8 12
DCS-7812 10 10 10 18
DCS-7816 12 12 12 24

Recommendations for Power Supply Usage

  • Use separate circuits (A & B) with required protection for each power supply.
  • Use the same PSU model when replacing a failed PSU. Any suitable alternative must be approved before using if the original model is no longer supported or available.
  • Unless your switch allows for mixing power supplies, do not mix power supply types.
  • To minimize distribution power loss, use an equal number of supplies in each row: (e.g 4 PSUs in slots 1-4 and 4 PSUs in slots 7-10 for a configuration with 8 PSUs for the DCS-7808 switch). Table 1 provides more details.

     

    Note: PSUs can be housed in either of two rows for the DCS-7808 switch. The LEDs for PSUs in each row indicate correct status only after at least one of the PSUs in that row (PSU1 to PSU6 or PSU7 to PSU12) is energized from a power source. For the DCS-7812 and DCS-7816 switches, as long as one PSU is powered, all PSU LEDs will report status correctly.

     

  • All power supply slots must be filled with a powered supply, or a blank (X), or a non-powered power supply.
  • Valid redundancy configurations for each domain are described in Power Supply Redundancy section.

Power Supply Redundancy

Important: Installation of this equipment must comply with local and national electrical codes. If necessary, consult with the appropriate regulatory agencies and inspection authorities to ensure compliance.

 

Installation de cet équipement doit être conformes aux codes électriques locaux et nationaux. Si nécessaire, consulter les organismes de réglementation appropriés et des autorités de contrôle pour assurer la conformité.

 

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.

 

Most installations will have redundant, dual, independent power feeds. Each independent power feed will be referenced as A and B.

 

The recommended installation is to wire input_A and input_B of each supply to independent power feed (A or B).
Note: When powered cables are connected to both A and B inputs of the PSU, the AC PSU will draw current from the A input. The B input is held in standby. The DC PSU will share power based on the input voltage.

 

Each power supply includes a fan that maintains proper power supply temperature. The following appendices display the location of the following component on all switches described in this guide.

The Front Panel displays the front panel location of the supervisor modules, line cards and PSUs.

The Rear Panel displays the rear panel location of fabric modules.

Important: This unit requires over-current protection.

 

Cet appareil nécessite de protection contre les surintensités.

 

 

Important: Unused slots must be occupied or covered with a blank to ensure proper airflow through the chassis.

 

Les emplacements inutilisés doivent être occupés ou recouvert d'un blanc pour assurer la bonne circulation d'air dans le châssis.

 

Connecting Supervisor Cables

Supervisor modules contain console, management, and USB ports. Figure 8 displays port and status LED locations on the supervisors. Refer to the chassis specification in Figure 9 for additional information about the serial port.

Figure 8. Supervisor DCS-7800-SUP, DCS-7800-SUP1A, and DCS-7816-SUP

1 Locking mechanism 5 Line card status LED 9 RJ-45 Serial management port
2 Supervisor status LED 6 Fabric Module status LED 10 USB Ports
3 Supervisor active status LED 7 Fan status LED 11 RJ-45 Ethernet management port
4 PSU status LED 8 Clock In 12 SFP Ethernet management port

 

  • Console (Serial) Port:Connect to a PC with RJ-45 to DB-9 serial adapter cable. Default switch settings include:
    • 9600 baud
    • No flow control
    • 1 stop bit
    • No parity bits
    • 8 data bits

The appropriate supervisor cards must be installed in one of the two slots designated for them. They are shown in Figure 9 for the DCS-7808 switch. For the DCS-7816 switch, the supervisor slots are in the middle of the chassis.

Figure 9. DCS 7808 Supervisor Slots

1 Power supplies 4 Linecards 7 Supervisor lock
2 Linecard and Supervisor extraction tool tether 5 Linecard lock 8 Grounding locations
3 Extraction tool 6 Supervisor modules 9 ESD attach point

 

RJ-45 to DB-9 Connections

RJ-45 DB-9 RJ-45 DB-9
RTS 1 8 CTS GND 5 5 GND
DTR 2 6 DSR RXD 6 3 TXD
TXD 3 2 RXD DSR 7 4 DTR
GND 4 5 GND CTS 8 7 RTS

 

  • Ethernet management port: Connect to 10/100/1000 management network with RJ-45 cable.
  • USB Port: May be used for software or configuration updates.
  • Clock Input Port: Port type is MCX connector, 2-5.5V, 50 ohm termination.

Connecting Line Card Modules and Cables

Install required SFP, SFP+, QSFP+, QSFP100, OSFP, and QSFP-DD optic modules in line card module ports (Figure 10).

Figure 10. SFP or SFP+ Ports

Connect cables as required to line card module ports. Supervisor and line card module ejectors on the front of the chassis assist with cable management.

CAUTION: Excessive bending can damage interface cables, especially optical cables.

 

Flexion excessive peut endommager les câbles d'interface, en particulier les câbles optiques.

 

Note: You must ensure that any open slots for modules, power supplies, etc. are covered by the appropriate “blank” plates. Check with your local Arista Networks representative if you have questions.