Cisco CRS-16 DC Instruction Manual

Installing and Removing Power Components
This chapter provides instructions on how to install and remove Cisco CRS Carrier Routing System 16-Slot
line card chassis power components.
This chapter presents the following topics:
•Power Component Information Common to the Two Types of Power Systems
•Installing and Remove Fixed Configuration Power Components
•Installing and Removing Modular Configuration Power Components
•Converting a Chassis from Fixed Configuration Power to Modular Configuration Power
•Power Systems Overview, on page 1
•Power Component Information Common to the Two Types of Power Systems, on page 2
•Installing and Remove Fixed Configuration Power Components , on page 15
•Installing and Removing Modular Configuration Power Components, on page 43
•Converting a Chassis from Fixed Configuration Power to Modular Configuration Power , on page 82
Power Systems Overview
There are two options for power systems: the fixed configuration power system and the modular configuration
power system. Power components are not interchangeable between the fixed and modular configuration power
system.
•Fixed configuration power system
Consists of two power shelves, DC power entry modules (PEMs) or AC rectifiers, and alarm modules. It is
available in versions for DC and AC power supplies. The AC version requires either 3-phase AC-Delta or
3-phase AC-Wye input power to the power shelves. It provides power sharing across power zones. The fixed
configuration power system includes SNMP MIBS and XML support.
•Modular configuration power system
Consists of two power shelves, AC or DC power modules (PMs), and alarm modules. It is available in versions
for DC and AC power supplies. However, unlike the fixed configuration power system, the AC version of
the modular configuration power system requires single-phase AC input power to the power shelves; there is
no 3-phase AC-Wye or AC-Delta. If you have 3-phase AC Delta or AC Wye at your equipment, a Cisco CRS
power distribution unit (PDU) will be required to convert 3-phase AC input power to single-phase AC input
power for the power shelf. At the shelf level, the power system provides 2N redundancy; the PMs themselves
Installing and Removing Power Components
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provide load-share redundancy. The modular configuration power system also includes SNMP MIBS and
XML support.
In a modular configuration AC power system, PDU refers to the Cisco CRS PDU which is required to convert
3-phase AC-Wye or AC-Delta input power to single-phase AC input power for the modular configuration
AC power shelf. For further information, see the Cisco CRS 3-Phase AC Power Distribution Unit Installation
Guide .
Note
Power Component Information Common to the Two Types of
Power Systems
This section introduces information shared by the fixed configuration power components and the modular
configuration power components in the following topics:
• Basic Chassis Power Details
• Bonding and Grounding Guidelines
• DC Power Systems
• AC Power Systems
Basic Chassis Power Details
The LCC can be configured with either an AC-input power subsystem or a DC-input power subsystem. Site
power requirements differ, depending on the source voltage used. Follow these precautions and
recommendations when planning power connections to the router:
• Check the power at your site before installation and periodically after installation to ensure that you are
receiving clean power. Install a power conditioner, if necessary.
• Install proper grounding to avoid damage from lightning and power surges.
The LCC requires that at least one power shelf and its components be installed to operate properly; however,
if you install only one power shelf and its components, your system will not be 2N redundant.
Two types of power shelves exist: an AC shelf and a DC shelf. A fixed configuration AC power shelf houses
the AC rectifiers, while a fixed configuration DC power shelf houses the DC PEMs. A modular configuration
AC power shelf houses the AC PMs, while a modular configuration DC power shelf houses the DC PMs. It
is required that you use only one type of power shelf in a chassis at a time.
In a modular configuration power system, both AC and DC power supplies are referred to as power modules
(PMs).
Note
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Installing and Removing Power Components
Power Component Information Common to the Two Types of Power Systems

The chassis might have more than one power connection. All connections must be removed to de-energize
the chassis. Statement 1028
Caution
Bonding and Grounding Guidelines
The router chassis has a safety earth ground connection in conjunction with power cabling to the fixed
configuration power shelves. The chassis allows you to connect the central office ground system or interior
equipment grounding system to the bonding and grounding receptacles on the router chassis, when either a
fixed or modular configuration power system is installed. Two threaded ground inserts are located on top of
the chassis rear (MSC) side panel to the left of the lower power shelf. The following figure shows the NEBS
and grounding points on the rear (MSC) side of the chassis with a modular configuration DC power shelf
installed. This grounding point is also referred to as the network equipment building system (NEBS) bonding
and grounding stud. The location of the grounding points on the LCC is the same for both fixed and modular
configuration power systems.
These bonding and grounding receptacles are provided to satisfy the Telcordia NEBS requirements for bonding
and grounding connections.
Note
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Installing and Removing Power Components
Bonding and Grounding Guidelines

Figure 1: NEBS Bonding and Grounding Points—Modular Configuration DC Power Shown
NEBS bonding and grounding points2Chassis ground cable1
The previous figure shows a 45-degree grounding. A 180-degree (straight) grounding lug can also be used.
Note
Do not remove the chassis ground cable unless the chassis is being replaced.
Caution
The grounding points are hidden by a cover plate. When the cover plate is removed, you can easily see the
labels indicating the location of the grounding points. Two grounding points are provided; use the top grounding
point for NEBS grounding purposes.
Modular configuration power shelf grounding is accomplished by installing an external ground bracket between
the power shelves and attached to the chassis, as shown in the next figure. The bolts that connect the external
grounding brackets to the chassis and the power shelf have a torque value of 30 in.-lb (3.39 N-m). See Installing
Power Shelf Grounding Brackets for more information about installing power shelf grounding brackets.
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Bonding and Grounding Guidelines

Figure 2: Power Shelf Grounding Brackets—Modular Configuration DC Power Shown
Two M6 hex nuts attaching grounding L-bracket to
shelf grounding bracket
5Chassis ground cable1
Grounding L-bracket6Two M6 hex bolts attaching ground lug to chassis2
Four M6 hex bolts attaching shelf grounding bracket
to power shelves
7Shelf grounding bracket3
Two M6 hex bolts attaching grounding L-bracket
to chassis
4
Installing the Chassis Ground Cable
This section describes how to install the ground cable on the LCC.
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Installing and Removing Power Components
Installing the Chassis Ground Cable

Prerequisites
To ensure a satisfactory ground connection, you need the following parts:
• One grounding lug that has two M6 bolt holes with 0.63 inches (5/8 inch) (1.60 cm) of spacing center
to center between them and a 6 AWG or larger multi strand copper wire. The grounding lug used can be
either a 180 degree (straight) lug or a 45-degree lug.
Figure 3: 180-Degree (Straight) Chassis Ground Lug
Figure 4: 45-Degree Chassis Ground Lug
• Two M6 hex head bolts and integrated locking washers are pre-installed on the chassis.
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Installing and Removing Power Components
Prerequisites

• Although we recommend at least 6 AWG multistrand copper ground cable, the actual cable diameter
and length depends on the router location and site environment. This cable is not available from Cisco
Systems; it is available from any commercial cable vendor. The cable should be sized according to local
and national installation requirements.
The DC return of this system should remain isolated from the system frame and chassis (DC-I: Isolated DC
Return).
Note
Required Tools and Equipment
• Ground lug
• Ground cable
• Crimping tool and lug specific die
• 10-mm 6 pt. combination wrench
• Torque wrench with 10-mm 6 pt. socket and rated accuracy at 30 in.-lb (3.39 N-m)
Steps
To attach the ground cable to the chassis, follow these steps:
SUMMARY STEPS
1. Use the crimping tool mandated by the lug manufacturer to crimp the lug to the ground cable.
2. Using the 10-mm wrench, attach the ground cable to the grounding point on top of the chassis rear (MSC)
side panel, as shown Figure 1: NEBS Bonding and Grounding Points—Modular Configuration DC Power
Shown. Then use the torque wrench to tighten to a torque of 30 in.-lb (3.39 N-m).
DETAILED STEPS
Step 1 Use the crimping tool mandated by the lug manufacturer to crimp the lug to the ground cable.
Step 2 Using the 10-mm wrench, attach the ground cable to the grounding point on top of the chassis rear (MSC) side panel, as
shown Figure 1: NEBS Bonding and Grounding Points—Modular Configuration DC Power Shown. Then use the torque
wrench to tighten to a torque of 30 in.-lb (3.39 N-m).
DC Power Systems
Each DC powered chassis contains two DC power shelves for 2N redundancy. The shelves contain the input
power connectors.
• In the fixed configuration power system, each power shelf contains three DC PEMs. The power shelves
and DC PEMs are field replaceable. Each DC PEM has its own circuit breaker.
•In the modular configuration power system, each shelf can accept up to eight DC PMs. The power shelves
and DC PMs are field replaceable.
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Installing and Removing Power Components
Required Tools and Equipment

Depending on the hardware deployed at your site, your system may not consume the maximum power supplied
by the power system.
Note
Fixed Configuration DC Power
The LCC fixed configuration DC power system provides 13,200 watts to power the chassis.
Due to its power zones, the LCC using fixed configuration power requires a total of twelve dedicated 60 Amp
DC input power connections, two for each DC PEM, to provide redundant DC power to all six power zones.
We recommend that you have two separate, redundant –48 VDC power battery sources to provide power to
the LCC. Connect the six “A" 60 Amp DC inputs to the upper power shelf (PS0 in Figure 1-4) to one battery,
and the six “B” 60 Amp inputs to the lower power shelf (PS1 in Figure 1-4) to the other battery.
At sites where the LCC is equipped with a DC-input power supply shelf and DC PEMs, observe the following
guidelines:
• All power connection wiring should follow the rules and regulations in the National Electrical Code
(NEC) and any local codes.
• Each DC-input PEM connection is rated at 60 A maximum. A dedicated, commensurately rated DC
power source is required for each PEM connection.
• For DC power cables, we recommend that you use commensurately rated, high-strand-count copper
cable. Each DC PEM requires two DC inputs of nominal –48/–60 VDC, 60 A service. Each DC input
consists of one pair of cable leads, source DC (–) and source DC return (+). Each power shelf requires
one grounding cable. The length of the cables depends on the router location. These cables are not
available from Cisco Systems; they are available from any commercial vendor.
• DC power cables must be terminated by cable lugs at the power shelf end. The lugs should be dual hole
and able to fit over M6 terminal studs at 0.63 in. (5/8 in.) (1.60 cm) centers (for example, Panduit part
number LCD2-14A-Q), as shown in the next figure.
• Maximum wire size at the DC input terminal block is 2 AWG.
Figure 5: DC Power Cable Lug
The next figure shows a typical source DC power distribution scheme. The ground cable is to the far left on
the shelf. The DC terminal block cable connector screws have a 20 in.-lb (2.26 N-m) value; the power shelf
ground cable connector screws have a 30 in.-lb (3.39 N-m) torque value.
The color coding of the source DC power cable leads depends on the color coding of the site DC power source.
Typically, green or green and yellow indicates that the cable is a ground cable. Follow your local practices
for cable color code and markings. Ensure that the power cables are connected to the DC input power shelf
terminal studs in the proper positive (+) polarity and negative (–) polarity.
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Installing and Removing Power Components
Fixed Configuration DC Power

Sometimes, the source DC cable leads might have a positive (+) or a negative (–) label, but you must verify
the polarity by measuring the voltage between the DC cable leads. When making the measurement, the positive
(+) lead and the negative (–) lead must always match the (+) and (–) labels on the power shelf.
The DC input PEM contains circuitry to trip the breaker on the PEM if it detects a reverse polarity condition.
When installing DC power cables, make sure that the polarity of the DC input wiring is correct.
Caution
This figure shows the cable wiring for the fixed configuration power shelf.
Figure 6: DC Power Shelf Cable Wiring for Fixed Configuration Power Shelf
The table lists the fixed configuration DC input current and voltage specifications.
Table 1: DC Input Current and Voltage Information
–48 VDC North America–60 VDC European Community(range: –42 VDC to –75
VDC)
Nominal input voltage
50 A maximum at –48 VDC40 A maximum at –60 VDCInput line current
168 A peak at –75 VDC(maximum for 1 ms)Inrush current
Each wiring block on the fixed configuration power shelf contains two sets of terminals, one positive and one
negative, and is covered by a plastic block cover that snaps onto the power shelf and is secured by a screw to
a torque value of 4 to 5 in.-lb (0.46 to 0.58 N-m). You must remove the block cover or rotate it out of the way
before you work with the cables. The block covers are slotted in such a way that the cables can exit only one
end. For the cables to point in a different direction, remove the block cover, rotate it, and snap it back on.
Modular Configuration DC Power
The LCC modular configuration DC power system can provide up to 16,800 watts to power the chassis.
However, by default, the power capability of a system when shipped, with six DC PMs per power shelf, is
12,600 watts.
Depending on the hardware deployed at your site, your system may not consume the maximum power supplied
by the power system.
Note
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Installing and Removing Power Components
Modular Configuration DC Power

Each modular configuration DC power shelf supports up to eight DC PMs. The power shelves and DC PMs
are field replaceable.
Although each modular configuration DC power shelf can support up to eight DC PMs, the modular
configuration DC power shelf is shipped with six DC PMs per shelf.
Note
This figure shows the cable wiring for the modular configuration power shelf.
Figure 7: DC Power Shelf Cable Wiring for Modular Configuration Power Shelf
Each power shelf operates with up to eight DC inputs of –48/–60 VDC (nominal), 60A. The power shelf
accepts input DC power in the range –40 to –72 VDC.
This table lists the modular configuration DC input current and voltage specifications.
Table 2: DC Input Current and Voltage Information
–48 VDC North America–60 VDC European Community(range: –40 VDC to –72
VDC)
Nominal input voltage
50 A maximum at –48 VDC40 A maximum at –60 VDC60 A maximum at –40 VDCInput line current
Each wiring block on the modular configuration DC power shelf contains two sets of terminals, one positive
and one negative, and is covered by a plastic terminal block cover that is secured by a screw to a torque of 5
to 7 in.-lb (0.56 to 0.79 N-m). Each DC power cable is connected to the power shelf with a torque of 20 in.-lb
(2.26 N-m). Maximum wire size at the DC input terminal block is 2 AWG.
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Installing and Removing Power Components
Modular Configuration DC Power

The power supply terminal posts are centered 0.63 inches (5/8 inch) (1.60 cm) apart and are M6-threaded.
We recommend that you use an appropriately sized 180-degree angle (straight) industry standard 2-hole,
standard barrel compression lug, as shown in this figure.
Figure 8: DC Power Cable Lug
The power shelf grounding is accomplished by installing an external ground bracket between the power shelves
and attached to the chassis. The bolts that connect the external grounding brackets to the chassis and the power
shelf have a torque value of 30 in.-lb (3.39 N-m).
Input-Power-Present LEDs
In both power configurations, the DC input-power-present LEDs provide a visual indication to service personnel
that there is voltage present across the input terminal connection. The LED provides a warning to the service
person that there is power present.
Power should be disconnected before servicing the input power connection.
Note
This figure shows the input-power-present LEDs on the rear of the fixed configuration DC power shelf.
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Installing and Removing Power Components
Input-Power-Present LEDs

Figure 9: Input-Power-Present LEDs—Fixed Configuration DC Power Shown
This figure shows the input-power-present LEDs on the rear of the modular configuration DC power shelf.
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Installing and Removing Power Components
Input-Power-Present LEDs

Figure 10: Input-Power-Present LEDs—Modular Configuration DC Power Shown
The input-power-present LED starts to light up when the input voltage reaches –20 VDC and the LED gets
brighter as voltage increases; the input-power-present LED is fully lit when the input voltage reaches –38
VDC.
If the input voltage polarity is reversed, or if the LED circuit fails, the LED will not light. When this is the
case, service personnel should check for hazardous voltages before working on the unit.
Caution
AC Power Systems
Each AC powered chassis contains two AC power shelves for 2N redundancy. The shelves contain the input
power connectors.
•In the fixed configuration power system, each shelf contains three AC power rectifiers. The power shelves
and AC power rectifiers are field replaceable. Each shelf and AC power rectifier has its own circuit
breaker.
• In the modular configuration power system, each shelf can contain up to six AC PMs. The power shelves
and the AC PMs are field replaceable.
Depending on the hardware deployed at your site, your system may not consume the maximum power supplied
by the power system.
Note
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Installing and Removing Power Components
AC Power Systems

Fixed Configuration AC Power
The LCC fixed configuration AC power system provides 13,200 watts to power the chassis.Two versions of
the 3-phase AC power shelf are available to provide either an AC Delta or an AC Wye input configuration.
Each of the AC power shelf versions has a different Cisco part number to distinguish the Wye from the Delta
configuration. The AC connections to the LCC are made to terminal blocks on the AC power shelves that
have been hard wired for a Wye or Delta configuration. All chassis should have two power shelves of the
same type, that is, two Delta or two Wye AC power shelves.
In the fixed configuration power system, each shelf supports three AC-to-DC rectifiers that are field replaceable.
The AC-to-DC rectifiers convert 200-to-240 VAC power to –54 VDC used by the LCC.
The AC Wye power shelf has a Wye 3-phase, 5-wire connection: 200 to 240 (L-N)/346 to 415 (L-L) VAC,
3W+N+PE, 50 to 60 Hz, 25 A. For redundant operation, two 3-phase Wye branch circuits are required: 40 A
(North America) or 32 A (International). One power connection is required for each power shelf.
The AC Delta power shelf has a Delta 3-phase, 4-wire connection: 200 to 240 VAC, 3-phase, 3W+PE, 50 to
60 Hz, 42 A. For redundant operation, two 3-phase Delta 60-A branch circuits are required. One power
connection is required for each power shelf.
The power cord for the fixed configuration AC power shelf does not arrive preattached and needs to be
installed.
Note
Modular Configuration AC Power
The LCC modular configuration AC power system can provide up to 18,000 watts to power the chassis.
However, by default, the power capability of a system when shipped, with 5 AC PMs per power shelf, is
15,000 watts.
Each modular configuration power shelf supports up to six PMs. The power shelves and PMs are field
replaceable.
Depending on the hardware deployed at your site, your system may not consume the maximum power supplied
by the power system.
Note
Unlike the fixed configuration AC power system, which requires 3-phase AC Delta or AC Wye input power,
the modular configuration AC power system requires single-phase AC input power. If you have 3-phase AC
Delta or AC Wye at your equipment, a Cisco CRS PDU will be required to convert 3-phase AC input power
to single-phase AC input power for the power shelf. For more information, see the Cisco CRS 3-Phase AC
Power Distribution Unit Installation Guide .
The modular configuration AC power shelf has the following input VAC power requirements:
• Single-phase, 200 to 240 VAC nominal, 50 to 60 Hz, 16 A.
Each power shelf contains six IEC-320-C22 receptacles which can accept up to six IEC-320-C21 connector
female cords.
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Installing and Removing Power Components
Fixed Configuration AC Power

If you have a Cisco CRS 3-Phase AC PDU installed, six AC PMs are required to be installed in each LCC
AC modular configuration power shelf to maintain a balanced 3-phase power load,.
Note
We recommend that you use appropriate short-circuit protection in compliance with national and local electrical
codes.
Note
Installing and Remove Fixed Configuration Power Components
This section contains the following procedures:
• Installing a Fixed Configuration Power Shelf
• Removing a Fixed Configuration Power Shelf
• Installing Fixed Configuration AC Power Cords
• Removing Fixed Configuration AC Power Cords
• Installing Fixed Configuration DC Power Shelf Wiring
• Removing Fixed Configuration DC Power Shelf Wiring
• Installing an AC Rectifier or DC PEM
• Removing an AC rectifier or DC PEM
• Installing a Fixed Configuration Alarm Module
• Removing a Fixed Configuration Alarm Module
• Powering Up and Down a Chassis with Fixed Configuration AC Power
• Power Up and Power Down a Chassis with Fixed Configuration DC Power
• Converting from One Fixed Configuration Power System to Another
For complete information on regulatory compliance and safety, see Cisco CRS Carrier Routing System
Regulatory Compliance and Safety Information.
Note
Installing a Fixed Configuration Power Shelf
This section describes how to install a fixed configuration power shelf in the LCC. For information on the
differences between the power types, see DC Power Systems and AC Power Systems.
The power shelf encloses:
• The power modules: three AC rectifiers for an AC power shelf or three DC PEMs for a DC power shelf
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Installing and Removing Power Components
Installing and Remove Fixed Configuration Power Components

• An alarm module
• Power distribution connections and wiring.
The power shelf is installed in the LCC from the front (PLIM) side. Although differences exist among the
different power shelf types (AC Wye, AC Delta, and DC), they are installed in the same manner. This figure
shows a fixed configuration AC power shelf. The fixed configuration DC power shelf is similar.
Figure 11: AC Wye Power Shelf with AC Rectifiers Installed
Power shelf captive screws3Lever handle captive screws1
Power shelf I/O switch4Lever handle (left handle shown)2
Prerequisites
Before performing this task, remove the upper grille on the front (PLIM) side of the chassis (if installed).
Do not install the power shelf in the chassis with DC PEMs, AC rectifiers, or alarm module installed in the
power shelf.
Note
Required Tools and Equipment
You need the following tools and part to perform this task:
• ESD-preventive wrist strap
• 1/4-in. x 6-in. long slotted screwdriver
• Fixed configuration AC or DC power shelf
• AC Delta power shelf (Cisco product number CRS-16-LCC-PS-ACD=), or
• AC Wye power shelf (Cisco product number CRS-16-LCC-PS-ACW=), or
• DC power shelf (Cisco product number CRS-16-LCC-PS-DC=)
Steps
To install a fixed configuration power shelf, perform the following steps:
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Prerequisites

SUMMARY STEPS
1. Attach the ESD-preventive wrist strap to your wrist and connect its leash to one of the ESD connection
sockets on the front (PLIM) side of the chassis or a bare metal surface on the chassis.
2. Make sure that the power shelf I/O switch, located on the front (PLIM) side of the chassis, is in the OFF
position.
3. The lever handles are fastened down for shipment. Use the screwdriver to turn the two captive screws,
one on each lever handle, to unfasten them.
4. Supporting the unit by the bottom and grasping one side for balance, lift the power shelf up and slide it
into one of the power shelf slots on the chassis.
5. Slide the power shelf fully into the chassis and lift the lever handles up to lock the tray into position.
6. Use the screwdriver to turn the two lever screws on the front panel of the power shelf clockwise to seat
the power shelf firmly in the slot.
7. Use the screwdriver to turn the four captive screws on the interior of the power shelf clockwise to firmly
anchor the shelf to the sides of the chassis.
DETAILED STEPS
Step 1 Attach the ESD-preventive wrist strap to your wrist and connect its leash to one of the ESD connection sockets on the
front (PLIM) side of the chassis or a bare metal surface on the chassis.
Step 2 Make sure that the power shelf I/O switch, located on the front (PLIM) side of the chassis, is in the OFF position.
Step 3 The lever handles are fastened down for shipment. Use the screwdriver to turn the two captive screws, one on each lever
handle, to unfasten them.
Step 4 Supporting the unit by the bottom and grasping one side for balance, lift the power shelf up and slide it into one of the
power shelf slots on the chassis.
An empty power shelf weighs approximately 36 lb (16.3 kg). Because of the rack-mounted height of the chassis,
you should be especially careful while lifting and removing the power shelf. To prevent injury, keep your back
straight and lift with your legs, not your back. Avoid sudden twists or lateral moves. It is safer to use two people
and a ladder to install or remove the power shelf rather than a single person.
Caution
Step 5 Slide the power shelf fully into the chassis and lift the lever handles up to lock the tray into position.
Step 6 Use the screwdriver to turn the two lever screws on the front panel of the power shelf clockwise to seat the power shelf
firmly in the slot.
Step 7 Use the screwdriver to turn the four captive screws on the interior of the power shelf clockwise to firmly anchor the shelf
to the sides of the chassis.
What to do next
After performing this task, wire the power shelf (Installing Fixed Configuration AC Power Cords and Installing
Fixed Configuration DC Power Shelf Wiring), install the power modules (Installing an AC Rectifier or DC
PEM) and install the alarm module (Installing a Fixed Configuration Alarm Module).
Removing a Fixed Configuration Power Shelf
This section describes how to remove a power shelf from the 16-slot LCC. For information on the differences
between the power types, see DC Power Systems and AC Power Systems.
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Installing and Removing Power Components
Removing a Fixed Configuration Power Shelf

The power shelf is installed and removed from the front (PLIM) side and plugs into the chassis power interface
connector panel. Although differences exist among the different power shelf types (AC Wye, AC Delta, and
DC), they are installed and removed in the same manner. Figure 11: AC Wye Power Shelf with AC Rectifiers
Installed shows a fixed configuration AC power shelf.
Prerequisites
Before performing this task, remove the upper grille on the front (PLIM) side of the chassis (if installed), and
power down and remove AC rectifiers (or DC PEMs) and the alarm module in the shelf you want to remove.
Remove the AC or DC power shelf wiring. See Removing an AC rectifier or DC PEM,Removing a Fixed
Configuration Alarm Module ,Removing Fixed Configuration AC Power Cords and Removing Fixed
Configuration DC Power Shelf Wiring.
Required Tools and Equipment
You need the following tools to perform this task:
• ESD-preventive wrist strap
• 1/4-in. x 6-in. long slotted screwdriver
Steps
To remove a fixed configuration AC or DC power shelf, perform the following steps:
SUMMARY STEPS
1. Attach the ESD-preventive wrist strap to your wrist and connect its leash to one of the ESD connection
sockets on the front (PLIM) side of the chassis or a bare metal surface on the chassis.
2. Turn the shelf power switch, located on the front (PLIM) side of the chassis, to the OFF position.
3. For AC, at the AC service circuit breaker box open all associated equipment circuit breakers for shelf(s)
to be removed. Use the lockout and tag procedures per your local practices. Unplug the power cords from
the associated power shelves and remove. See Removing Fixed Configuration AC Power Cords for more
information.
4. Remove all power modules (three AC power rectifiers in an AC power shelf or three DC PEMs in a DC
power shelf) from the shelf you are removing.
5. Remove the alarm module.
6. Use the screwdriver to loosen the four captive screws (two on each side) on the interior of the power shelf
by turning them counterclockwise.
7. Use the screwdriver to loosen the two lever screws on the front panel of the power shelf by turning them
counterclockwise.
8. Pull the lever handles down with both hands and slide the power shelf slowly from the slot in the chassis.
After partially removing the power shelf from the chassis using the handles, grab both side of the power
shelf and slide the shelf completely from the chassis.
9. Set the power shelf carefully aside.
DETAILED STEPS
Step 1 Attach the ESD-preventive wrist strap to your wrist and connect its leash to one of the ESD connection sockets on the
front (PLIM) side of the chassis or a bare metal surface on the chassis.
Step 2 Turn the shelf power switch, located on the front (PLIM) side of the chassis, to the OFF position.
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Installing and Removing Power Components
Prerequisites

Step 3 For AC, at the AC service circuit breaker box open all associated equipment circuit breakers for shelf(s) to be removed.
Use the lockout and tag procedures per your local practices. Unplug the power cords from the associated power shelves
and remove. See Removing Fixed Configuration AC Power Cords for more information.
For DC, at the BDFB or power plant, remove the associated fuses / circuit breakers for shelf(s) to be removed. Use the
lockout and tag procedures per your local practices. Remove DC distribution cables from the rear of the associated power
shelf and tape the bare lugs for protection. See Removing Fixed Configuration DC Power Shelf Wiring for more
information.
Step 4 Remove all power modules (three AC power rectifiers in an AC power shelf or three DC PEMs in a DC power shelf)
from the shelf you are removing.
Step 5 Remove the alarm module.
Step 6 Use the screwdriver to loosen the four captive screws (two on each side) on the interior of the power shelf by turning
them counterclockwise.
Step 7 Use the screwdriver to loosen the two lever screws on the front panel of the power shelf by turning them counterclockwise.
Step 8 Pull the lever handles down with both hands and slide the power shelf slowly from the slot in the chassis. After partially
removing the power shelf from the chassis using the handles, grab both side of the power shelf and slide the shelf
completely from the chassis.
An empty power shelf weighs approximately 36 lb (16.3 kg). Because of the rack-mounted height of the chassis,
you should be especially careful while lifting and removing the power shelf. To prevent injury to your back,
keep your back straight while lifting the shelf and lift the equipment as you stand up. Avoid sudden twists or
lateral moves. It is safer to have two people use a ladder to install or remove the power shelf rather than do it
yourself.
Caution
Step 9 Set the power shelf carefully aside.
What to do next
After performing this task, you can install a replacement power shelf (Installing a Fixed Configuration Power
Shelf).
Installing Fixed Configuration AC Power Cords
This section describes how to install the AC Wye and AC Delta power cord in the fixed configuration power
system.
Prerequisites
Before performing this task, ensure that both power shelves are installed in the chassis. Remove the upper air
grille on the rear [MSC] side of the chassis (if installed).
Before installing the AC power cord on the power shelf, make sure that the AC power cord is not plugged
into the facility power.
Note
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Installing and Removing Power Components
Installing Fixed Configuration AC Power Cords

Required Tools and Equipment
You need the following tools to perform this task:
• ESD-preventive wrist strap
• 10-mm socket wrench
• Stripping tool to remove power cable conductor insulation
• 1/4-in. x 6-in. long slotted screwdriver
• Torque screwdriver with 1/4-in. slotted head and rated accuracy at 9 in-lb (1.04 N-m)
• Torque wrench with 10-mm 6 pt. socket and rated accuracy at 20 in.-lb (2.26 N-m)
AC Wye Power Shelf
The AC Wye power shelf arrives with a 5-wire Wye cord and an IEC 60309 plug rated 415 V/32 A, IP44,
3W+N+PE; it is 4 meters long. The power shelf has five corresponding terminations: three active (hot), one
neutral, and one ground. The ground lug and terminal block are located behind a removable cover on the rear
of the power shelf. The terminal block contains four terminations to attach the three active cable conductors
and one neutral cable conductor from the input power cord. The ground cable conductor from the input power
cord is attached to the ground lug.
The rear of the AC Wye power shelf with the rear cover removed is shown in this figure.
Figure 12: AC Wye Power Shelf Rear
Lead 4 (L4, neutral)4Lead 1 (L1)1
Ground5Lead 2 (L2)2
Lead 3 (L3)3
Leads 1, 2, and 3 (L1, L2, and L3) are not associated with any particular color of cable conductor because
they are not connected to neutral (L4) or the safety ground (L5).
Note
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Installing and Removing Power Components
Required Tools and Equipment