Connecting the EX4300 to Power

 

Connecting Earth Ground to an EX Series Switch

To ensure proper operation and to meet safety and electromagnetic interference (EMI) requirements, you must connect an EX Series switch to earth ground before you connect power to the switch. You must use the protective earthing terminal on the switch chassis to connect the switch to earth ground (see Figure 2).

Note

A ground connection to the protective earthing terminal is not required for an AC-powered switch. The AC power cords provide adequate grounding when you connect the power supply in the switch to a grounded AC power outlet by using the AC power cord appropriate for your geographical location.

Warning

The switch is installed in a restricted-access location.

Caution

If external ground connection is required, ensure that a licensed electrician has attached an appropriate grounding lug to the grounding cable that you supply. Using a grounding cable with an incorrectly attached lug can damage the switch.

Parts and Tools Required for Connecting an EX Series Switch to Earth Ground

Table 1 lists the earthing terminal location, grounding cable requirements, grounding lug specifications, screws and washers required, and the screwdriver needed for connecting a switch to earth ground. Before you begin connecting a switch to earth ground, ensure you have the parts and tools required for your switch.

Table 1: Parts and Tools Required for Connecting an EX Series Switch to Earth Ground

Switch

Earthing Terminal Location

Grounding Cable Requirements

Grounding Lug Specifications

Screws and Washers

Screwdriver

Additional Information

EX2200

Rear panel of the chassis

14 AWG (2 mm²), minimum 90° C wire, or as permitted by the local code

Panduit LCC10-14BWL or equivalent—

not provided

  • Two 10-32 x .25 in. screws with #10 split-lock washer—

    not provided

  • Two #10 flat washers—not provided

Phillips (+)

 number 2

 

EX2300-C

Rear panel of the chassis

14 AWG (2 mm²), minimum 90° C wire, or as permitted by the local code

Panduit LCC10-14AW-L or equivalent—

not provided

  • Two 10-32 x .25 in. screws with #10 split-lock washer—

    not provided

  • Two #10 flat washers—not provided

Phillips (+)

 number 2

 

EX2300

Rear panel of the chassis

  • EX2300 switches except EX2300-24MP and EX2300-48MP models—14 AWG (2 mm²), minimum 90°C wire, or as permitted by the local code

  • EX2300-24MP and EX2300-48MP models—14-10 AWG STR (2.5-6 mm²), 12-10 AWG SOL (4-6 mm²) minimum 90°C wire, or as permitted by the local code—not provided

  • EX2300 switches except EX2300-24MP and EX2300-48MP models—Panduit LCC10-14AW-L or equivalent—not provided

  • EX2300-24MP and EX2300-48MP models—Panduit LCA10-10L or equivalent—not provided

  • EX2300 switches except EX2300-24MP and EX2300-48MP models

    • Two 10-32 x .25 in. screws with #10 split-lock washer—not provided

    • Two #10 flat washers—not provided

  • EX2300-24MP and EX2300-48MP models

    • One Pan Phillips M 4 x 6 mm Nickel plated screw—provided

Phillips (+)

 number 2

 

EX3200

Rear panel of the chassis

14 AWG (2 mm²), minimum 90° C wire, or as permitted by the local code

Panduit LCC10-14BWL or equivalent—

not provided

  • Two 10-32 x .25 in. screws with #10 split-lock washer—

    not provided

  • Two #10 flat washers—

    not provided

Phillips (+)

 number 2

See Special Instructions to Follow Before Connecting Earth Ground to a Switch.

EX3300

Rear panel of the chassis

14 AWG (2 mm²), minimum 90° C wire, or as permitted by the local code

Panduit LCC10-14BWL or equivalent—

not provided

  • Two 10-32 x .25 in. screws with #10 split-lock washer—

    not provided

  • Two #10 flat washers—

    not provided

Phillips (+)

 number 2

 

EX3400

Rear panel of the chassis

14 AWG (2 mm²), minimum 90° C wire, or as permitted by the local code

Panduit LCC10-14AW-L or equivalent—

not provided

  • Two 10-32 x .25 in. screws with #10 split-lock washer—

    not provided

  • Two #10 flat washers—not provided

Phillips (+)

 number 2

 

EX4200

Left side of the chassis

14 WG (2 mm²), minimum 90° C wire, or as permitted by the local code

Panduit LCC10-14BWL or equivalent—

not provided

  • Two 10-32 x .25 in. screws with #10 split-lock washer—

    not provided

  • Two #10 flat washers—

    not provided

Phillips (+)

 number 2

See Special Instructions to Follow Before Connecting Earth Ground to a Switch.

EX4300

Left side of the chassis

14 AWG (2 mm²), minimum 90° C wire, or as permitted by the local code

Panduit LCC10-14BWL or equivalent—

not provided

  • Two 10-32 x .25 in. screws with #10 split-lock washer—

    not provided

  • Two #10 flat washers—

    not provided

Phillips (+)

 number 2

See Special Instructions to Follow Before Connecting Earth Ground to a Switch.

EX4500

Left side of the chassis

14 AWG (2 mm²), minimum 90° C wire, or as permitted by the local code

Panduit LCC10-14BWL or equivalent—

not provided

  • Two 10-32 x .25 in. screws with #10 split-lock washer—

    not provided

  • Two #10 flat washers—

    not provided

Phillips (+)

 number 2

See Special Instructions to Follow Before Connecting Earth Ground to a Switch.

EX4550

Left side of the chassis

14 AWG (2 mm²), minimum 90° C wire, or as permitted by the local code

Panduit LCC10-14BWL or equivalent—

not provided

  • Two 10-32 x .25 in. screws with #10 split-lock washer—

    not provided

  • Two #10 flat washers—

    not provided

Phillips (+)

 number 2

See Special Instructions to Follow Before Connecting Earth Ground to a Switch.

EX6210

Rear panel of the chassis (on lower left side)

The grounding cable must be the same gage as the power feed cables and as permitted by the local code.

Panduit LCD2-14A-Q or equivalent

—provided

  • Two ¼ -20 x 0.5 in. screws with #¼” split-washer

    —provided

  • Two #¼” flat washers—

    provided

Phillips (+)

 number 2

 

EX8208

Left side of the chassis

6 AWG (13.3 mm²), minimum 60° C wire, or as permitted by the local code

Panduit LCD2-14A-Q or equivalent

—provided

  • Two ¼ -20 x 0.5 in. screws with #¼” split-washer

    —provided

  • Two #¼” flat washers—

    provided

Phillips (+)

 number 2

 

EX8216

Two earthing terminals:

  • Left side of the chassis

  • Rear panel of the chassis

2 AWG (33.6 mm²), minimum 60° C wire, or as permitted by the local code

Panduit LCD2-14A-Q or equivalent

—provided

  • Two ¼ -20 x 0.5 in. screws with #¼” split-washer

    —provided

  • Two #¼” flat washers—

    provided

Phillips (+)

 number 2

See Special Instructions to Follow Before Connecting Earth Ground to a Switch.

EX9204

Rear panel of the chassis

One 6 AWG (13.3 mm²), minimum 60° C wire, or one that complies with the local code

Thomas& Betts LCN6-14 or equivalent—

provided

  • Two ¼ -20 x 0.5 in. screws with #¼” split-washer—

    provided

  • Two #¼” flat washers—

    provided

Phillips (+)

 number 2

See Grounding Cable and Lug Specifications for EX9200 Switches.

EX9208

Rear panel of the chassis

One 6 AWG (13.3 mm²), minimum 60° C wire, or one that complies with the local code

Thomas& Betts LCN6-14 or equivalent—

provided

  • Two ¼ -20 x 0.5 in. screws with #¼” split-washer—

    provided

  • Two #¼” flat washers—

    provided

Phillips (+)

 number 2

See Grounding Cable and Lug Specifications for EX9200 Switches.

EX9214

Rear panel of the chassis

One 6 AWG (13.3 mm²), minimum 60° C wire, or one that complies with the local code

Thomas& Betts LCN6-14 or equivalent—

provided

  • Two ¼ -20 x 0.5 in. screws with #¼” split-washer—

    provided

  • Two #¼” flat washers—

    provided

Phillips (+)

 number 2

See Grounding Cable and Lug Specifications for EX9200 Switches.

EX9251

Rear panel of the chassis

12 AWG (2.5 mm²), minimum 60° C wire, or one that complies with the local code—

not provided

Panduit LCD10-10A-L or equivalent—

not provided

Two 10-32 screws—

provided

Phillips (+)

 number 2

Grounding Cable and Lug Specifications for EX9251 Switches

Special Instructions to Follow Before Connecting Earth Ground to a Switch

Table 2 lists the special instructions that you might need to follow before connecting earth ground to a switch.

Table 2: Special Instructions to Follow Before Connecting Earth Ground to a Switch

Switch

Special Instructions

EX3200

Note: Some early variants of EX3200 switches for which the Juniper Networks model number on the label next to the protective earthing terminal is from 750-021xxx through 750-030xxx require 10-24x.25 in. screws.

EX4200

Note: Some early variants of EX4200 switches for which the Juniper Networks model number on the label next to the protective earthing terminal is from 750-021xxx through 750-030xxx require 10-24x.25 in. screws.

Note: The protective earthing terminal on an EX4200 switch mounted on four posts of a rack is accessible through the slot on the left rear bracket only if the rack is 27.5 in. (69.85 cm) through 30.5 in. (77.47 cm) deep for a switch mounted flush with the rack front and 29.5 in. (74.93 cm) through 32.5 in. (82.55 cm) deep for a switch mounted 2 in. (5.08 cm) recessed from the rack front. See Figure 1.

Figure 1: Connecting the Grounding Lug to a Switch Mounted on Four Posts of a Rack
Connecting the Grounding
Lug to a Switch Mounted on Four Posts of a Rack
  1
Protective earthing terminal
  3
Grounding lug
  2
Side mounting-rail
  4
Rear mounting-blade

Note: The brackets must be attached to the chassis before the grounding lug is attached. (The brackets are shown pulled away from the chassis so that the protective earthing terminal is seen.)

EX4300

Note: The protective earthing terminal on an EX4300 switch mounted on four posts of a rack is accessible through the slot on the left rear bracket only if the rack is 27.5 in. (69.85 cm) through 30.5 in. (77.47 cm) deep for a switch mounted flush with the rack front and 29.5 in. (74.93 cm) through 32.5 in. (82.55 cm) deep for a switch mounted 2 in. (5.08 cm) recessed from the rack front.

EX4500

Note: If you plan to mount your switch on four posts of a rack or cabinet, mount your switch in the rack or cabinet before attaching the grounding lug to the switch. See Mounting an EX4500 Switch on Four Posts in a Rack or Cabinet.

Note: The protective earthing terminal on an EX4500 switch mounted on four posts of a rack is accessible through the slot on the left rear bracket only if the rack is 27.5 in. (69.85 cm) through 30.5 in. (77.47 cm) deep for a switch mounted flush with the rack front and 29.5 in. (74.93 cm) through 32.5 in. (82.55 cm) deep for a switch mounted 2 in. (5.08 cm) recessed from the rack front.

EX4550

Note: The protective earthing terminal on an EX4550 switch mounted on four posts of a rack is accessible through the slot on the left rear bracket only if the rack is 27.5 in. (69.85 cm) through 30.5 in. (77.47 cm) deep for a switch mounted flush with the rack front and 29.5 in. (74.93 cm) through 32.5 in. (82.55 cm) deep for a switch mounted 2 in. (5.08 cm) recessed from the rack front.

EX8216

Note: Only one of the two protective earthing terminals needs to be permanently connected to earth ground.

Connecting Earth Ground to an EX Series Switch

To connect earth ground to a switch:

  1. Connect one end of the grounding cable to a proper earth ground, such as the rack in which the switch is mounted.
  2. Place the grounding lug attached to the grounding cable over the protective earthing terminal. See Figure 2.
    Figure 2: Connecting a Grounding Cable to an EX Series Switch
    Connecting a Grounding Cable to an EX Series Switch
  3. Secure the grounding lug to the protective earthing terminal with the washers and screws.
  4. Dress the grounding cable and ensure that it does not touch or block access to other switch components.Warning

    Ensure that the cable does not drape where people could trip over it.

Connecting AC Power to an EX4300 Switch

EX4300 switches support 350 W, 715 W, 1100 W, or 1400 W AC power supplies depending on the switch model. After you install at least one power supply, you can connect power to the switch.

Caution

Do not mix:

  • AC and DC power supplies in the same chassis

  • Power supplies with different airflow labels (AIR IN (AFI) and AIR OUT (AFO)) in the same chassis.

  • Fan modules with different airflow labels (AIR IN (AFI) and AIR OUT (AFO)) in the same chassis.

  • Power supplies and fan modules with different airflow labels (AIR IN (AFI) and AIR OUT (AFO)) in the same chassis.

Before you begin connecting AC power to an EX4300 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 device chassis to earth ground, if required by your site guidelines or installation. A ground connection to the protective earthing terminal is not required for an AC-powered EX4300 switch. The AC power cords provide adequate grounding when you connect the power supply in the switch to a grounded AC power outlet by using the AC power cord appropriate for your geographical location (see AC Power Cord Specifications for an EX4300 Switch).

    Caution

    For installations that require a separate grounding conductor to the chassis, have a licensed electrician complete this connection before you connect the switch to power. For instructions on connecting earth ground, see Connecting Earth Ground to an EX Series Switch.

  • Install the power supply in the chassis. For instructions on installing a power supply in an EX4300 switch, see Installing an AC Power Supply in an EX4300 Switch.

  • Install a dedicated suitably rated two pole circuit breaker as per local electric code to provide protection against short circuit and over current.

Ensure that you have the following parts and tools available:

  • A power cord appropriate for your geographical location (provided)

Note

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

To connect AC power to an EX4300 switch:

  1. Wrap and fasten one end of an ESD wrist strap around your bare wrist, and connect the other end of the strap to the ESD point on the switch.Note

    The power supply slots are at the right end of the rear panel on 24-port and 48-port switches, and at the left end on 32-port switches.Figure 3 shows how to connect an AC power cord to an AC power supply installed on 24-port or 48-port EX4300 switches. The procedure is the same for 32-port EX4300 switches.

  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 cover panel is installed over the second power supply slot.
  3. Locate the power cord and power cord retainer shipped with the switch; the cords have plugs appropriate for your geographical location. See AC Power Cord Specifications for an EX4300 Switch.
  4. Push the end of the retainer strip into the hole next to the inlet on the power supply face plate until it snaps into place. Ensure that the loop in the retainer strip faces toward the power cord.
  5. Press the small tab on the retainer strip to loosen the loop. Slide the loop until you have enough space to insert the power cord coupler into the inlet.
  6. Insert the power cord coupler firmly into the inlet.
  7. Slide the loop toward the power supply until it is snug against the base of the coupler.
  8. Press the tab on the loop and draw out the loop into a tight circle (see Figure 3 and Figure 4).
    Figure 3: Connecting an AC Power Cord to an AC Power Supply in EX4300 Switches Except EX4300-48MP and EX4300-48MP-S Switches
    Connecting
an AC Power Cord to an AC Power Supply in EX4300 Switches Except EX4300-48MP
and EX4300-48MP-S Switches
    Figure 4: Connecting an AC Power Cord to an AC Power Supply in EX4300-48MP and EX4300-48MP-S Switches
    Connecting
an AC Power Cord to an AC Power Supply in EX4300-48MP and EX4300-48MP-S
Switches
  9. If the AC power source outlet has a power switch, set it to the OFF (O) position.
  10. Insert the power cord plug into an AC power source outlet.
  11. If the AC power source outlet has a power switch, set it to the ON (|) position.
  12. Verify that the IN OK and OUT OK LEDs on each power supply are lit green.

    If the OUT OK LED is lit amber, remove power from the power supply, and replace the power supply (see Removing an AC Power Supply from an EX4300 Switch). Do not remove the power supply until you have a replacement power supply ready: the power supplies or a cover panel must be installed in the switch to ensure proper airflow.

    Caution

    We recommend that you install either a replacement power supply or a cover panel in the empty power supply slot to prevent chassis overheating and dust accumulation.

Connecting DC Power to an EX4300 Switch

EX4300 switches can be configured with up to two DC power supplies. After you install at least one power supply, you can connect power to the switch.

Note

EX4300-24T, EX4300-24P, EX4300-32F, EX4300-48T, EX4300-48T-AFI, EX4300-48P, EX4300-48MP, and EX4300-48MP-S models do not support DC power. EX4300-24T-S, EX4300-24P-S, EX4300-32F-S, EX4300-32F-DC, EX4300-48T-S, EX4300-48T-DC, EX4300-48T-DC-AFI, and EX4300-48P-S models support DC power.

Caution

Do not mix:

  • AC and DC power supplies in the same chassis

  • Power supplies with different airflow labels (AIR IN (AFI) and AIR OUT (AFO)) in the same chassis.

  • Fan modules with different airflow labels (AIR IN (AFI) and AIR OUT (AFO)) in the same chassis.

  • Power supplies and fan modules with different airflow labels (AIR IN (AFI) and AIR OUT (AFO)) in the same chassis.

Before you begin connecting DC power to an EX4300 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.

    Caution

    Ensure that you install the power supply module first and then install the DC input wire, before closing input breaker ON.

    Caution

    Before you connect power to the device, 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 device (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 Connecting Earth Ground to an EX Series Switch.

  • Install the power supply in the chassis. For instructions on installing a DC power supply in an EX4300 switch, see Installing a DC Power Supply in an EX4300 Switch.

Ensure that you have the following parts and tools available:

  • DC power source cables (14– 16  AWG) with ring lug (Molex 190700067 or equivalent) (not provided)

  • Phillips  (+) screwdriver, number 2 (not provided)

  • Multimeter (not provided)

  • A 14  AWG (2 mm²), minimum 90° C wire grounding cable, or one permitted by the local code, with a Panduit LCC10-14BWL or equivalent grounding lug attached (not provided)

  • Two 10-32 x  .25  in. screws with #10 split-lock washer (not provided)

  • Two #10 flat washers (not provided)

To connect DC power to an EX4300 switch:

  1. Wrap and fasten one end of an ESD wrist strap around your bare wrist, and connect the other end of the strap to the ESD point on the switch.Note

    The power supply slots are at the right end of the rear panel on 24-port and 48-port switches, and at the left end on 32-port switches. Figure 5 shows how to secure ring lugs to the terminals on the DC power supply installed on 24-port or 48-port EX4300 switches. The procedure is the same for 32-port EX4300 switches.

  2. Verify that the DC power cables are correctly labeled before making connections to the power supply. In a typical power distribution scheme where the return is connected to chassis ground at the battery plant, you can use a multimeter to verify the resistance of the – 48V and RTN DC cables to chassis ground:
    • The cable with very low resistance (indicating a closed circuit) to chassis ground is positive  (+) and will be installed on the V+ (return) DC power input terminal.

    • The cable with very high resistance (indicating an open circuit) to chassis ground is negative  (–) and will be installed on the V– (input) DC power input terminal.

    Caution

    You must ensure that power connections maintain the proper polarity. The power source cables might be labeled (+) and (–) to indicate their polarity. There is no standard color coding for DC power cables. The color coding used by the external DC power source at your site determines the color coding for the leads on the power cables that attach to the DC power input terminals on each power supply.

  3. Ensure that the input circuit breaker is open so that the voltage across the DC power source cable leads is 0  V and that the cable leads will not become active while you are connecting DC power.Note

    The V+ terminals are referred to as +RTN and V– terminals are referred to as – 48  V in DC Power Wiring Sequence Warning and DC Power Electrical Safety Guidelines.

  4. Ensure that the power supplies are fully inserted in the chassis.
  5. Remove the terminal block cover. The terminal block cover is a piece of clear plastic that snaps into place over the terminal block.
  6. Remove the screws on the terminals by using the screwdriver. Save the screws.Warning

    Ensure that the power cables do not block access to switch components or drape where people can trip on them.

    Note

    The DC power supply has five terminals, two positive terminals labeled V+ and two negative terminals labeled V– , for connecting the power supply to a dedicated DC power source by using the DC power source cables labeled positive  (+) and negative  (–), and one terminal for connecting the power supply to earth ground (see Figure 5). The V+ terminals are shunted internally together, as are the V– terminals to provide parallel current path.

  7. Connect one end of the grounding cable to a proper earth ground, such as the rack in which the switch is mounted.
  8. Place the grounding lug attached to the grounding cable over the earthing terminal on the DC power supply.
  9. Secure the grounding lug to the protective earthing terminal with the washers and screws.
  10. Dress the grounding cable and ensure that it does not touch or block access to other switch components.Warning

    Ensure that the cable does not drape where people could trip over it.

    Note

    To supply sufficient power, terminate the DC input wiring on a facility DC source that is capable of supplying a minimum of 20 A at – 48 VDC.

  11. Connect each power supply to the power source. Secure power source cables to the power supplies by screwing the ring lugs attached to the cables to the appropriate terminals by using the screw from the terminals (see Figure 5).
    • To connect a power supply to a power source:

      1. Secure the ring lug of the positive  (+) DC power source cable to one of the + terminals on the DC power supply.
      2. Secure the ring lug of the negative (–) DC power source cable to the –   terminal adjacent to the +  terminal that you connected to on the DC power supply.
      3. Connect the ground wire to earth ground if the switch is not in a grounded rack.
      4. Tighten the screws on the power supply terminals until they are snug by using the screwdriver. Do not overtighten— apply between 5  lb-in (0.56  Nm) and 6  lb-in (0.68 Nm) of torque to the screws.

      If you have a second installed power supply, connect it in the same way you did the first.

    • To connect one power supply to two power sources:

      1. Secure the ring lug of the positive  (+) DC power source cable from the first DC power source to a + terminal on the power supply.
      2. Secure the ring lug of the negative (–) DC power source cable from the first DC power source to the –   terminal adjacent to the +  terminal on the DC power supply to which you connected the ring lug of the positive  (+) DC power source cable from the first DC power source.
      3. Secure the ring lug of the positive (+) DC power source cable from the second DC power source to the other +  terminal on the power supply.
      4. Secure the ring lug of the negative  (–) DC power source cable from the second DC power source to the –   terminal adjacent to the +  terminal on the DC power supply to which you connected the ring lug of the positive  (+) DC power source cable from the second DC power source.
      5. Connect the ground wire to earth ground if the switch is not in a grounded rack.
      6. Tighten the screws on the power supply terminals on both the power supplies until snug using the screwdriver. Do not overtighten—apply between 8 lb-in. (0.9 Nm) and 9  lb-in. (1.02 Nm) of torque to the screws.

      If you have a second installed power supply, connect it in the same way you did the first.

    Figure 5: Securing Ring Lugs to the Terminals on the DC Power Supply
    Securing Ring Lugs
to the Terminals on the DC Power Supply
  12. Replace the terminal block cover.
  13. Close the input circuit breaker.
  14. Verify that the IN OK and OUT OK LEDs on the power supply are lit green and are on steadily.