User Guide
Table Of Contents
- Dell PowerEdge R720 and R720xd Owner's Manual
- About Your System
- Using The System Setup and Boot Manager
- Installing System Components
- Recommended Tools
- Front Bezel (Optional)
- Opening And Closing The System
- Inside The System
- Cooling Shroud
- System memory
- Hard Drives
- Removing A 2.5 Inch Hard-Drive Blank
- Installing A 2.5 Inch Hard-Drive Blank
- Removing A 2.5 Inch Hard-Drive Blank (Back)
- Installing A 2.5 Inch Hard-Drive Blank (Back)
- Removing A 3.5 Inch Hard-Drive Blank
- Installing A 3.5 Inch Hard-Drive Blank
- Removing A Hot-Swap Hard Drive
- Installing A Hot-Swap Hard Drive
- Removing A Hard Drive From A Hard-Drive Carrier
- Installing A Hard Drive Into A Hard-Drive Carrier
- Optical Drive (Optional)
- Cooling Fans
- Internal USB Memory Key (Optional)
- PCIe Card Holder
- Top Cover Lock Latch
- Cable Retention Bracket
- Expansion Cards And Expansion-Card Risers
- Expansion Card Installation Guidelines
- Removing An Expansion Card From The Expansion-Card Riser 2 Or 3
- Installing An Expansion Card Into The Expansion-Card Riser 2 Or 3
- Removing An Expansion Card From The Expansion-Card Riser 1
- Installing An Expansion Card Into The Expansion-Card Riser 1
- Removing Expansion-Card Risers
- Installing Expansion-Card Risers
- GPU Card Installation Guidelines
- Installing A GPU Card
- Removing A GPU Card
- SD vFlash Card
- Internal Dual SD Module
- Internal SD Card
- Integrated Storage Controller Card
- Network Daughter Card
- Processors
- Power Supplies
- System Battery
- Hard-Drive Backplane
- Control Panel Board
- System Board
- Troubleshooting Your System
- Safety First—For You And Your System
- Troubleshooting System Startup Failure
- Troubleshooting External Connections
- Troubleshooting The Video Subsystem
- Troubleshooting A USB Device
- Troubleshooting A Serial I/O Device
- Troubleshooting A NIC
- Troubleshooting A Wet System
- Troubleshooting A Damaged System
- Troubleshooting The System Battery
- Troubleshooting Power Supplies
- Troubleshooting Cooling Problems
- Troubleshooting Cooling Fans
- Troubleshooting System Memory
- Troubleshooting An Internal USB Key
- Troubleshooting An SD Card
- Troubleshooting An Optical Drive
- Troubleshooting A Tape Backup Unit
- Troubleshooting A Hard Drive
- Troubleshooting A Storage Controller
- Troubleshooting Expansion Cards
- Troubleshooting Processors
- Using System Diagnostics
- Jumpers And Connectors
- Technical Specifications
- System Messages
- Getting Help

Wiring Instructions For A DC Power Supply
Your system supports up to two –(48–60) V DC power supplies (when available).
WARNING
: For equipment using –(48–60) V DC power supplies, a qualified electrician must perform all
connections to DC power and to safety grounds. Do not attempt connecting to DC power or installing grounds
yourself. All electrical wiring must comply with applicable local or national codes and practices. Damage due to
servicing that is not authorized by Dell is not covered by your warranty. Read and follow all safety instructions that
came with the product.
CAUTION
: Wire the unit with copper only, unless otherwise specified, use only 10 American Wire Gauge (AWG)
wire rated minimum 90 ºC for source and return. Protect the –(48–60) V DC (1 wire) with a branch circuit over-
current protection rated 50 A for DC with a high interrupt current rating.
CAUTION
: Connect the equipment to a –(48–60) V DC supply source that is electrically isolated from the AC source
(reliably grounded –(48–60) V DC SELV source). Ensure that the –(48–60) V DC source is efficiently secured to earth
(ground).
NOTE
: A readily accessible disconnect device that is suitably approved and rated shall be incorporated in the field
wiring.
Input Requirements
• Supply voltage: –(48–60) V DC
• Current consumption: 32 A (maximum)
Kit Contents
• Dell part number 6RYJ9 terminal block or equivalent (1)
• #6-32 nut equipped with lock washer (1)
Required Tools
Wire-stripper pliers capable of removing insulation from size 10 AWG solid or stranded, insulated copper wire
NOTE
: Use alpha wire part number 3080 or equivalent (65/30 stranding)
Required Wires
• One UL 10 AWG, 2 m maximum (stranded) black wire [–(48–60) V DC]
• One UL 10 AWG, 2 m maximum (stranded) red wire (V DC return)
• One UL 10 AWG, 2 m maximum green/yellow, green with a yellow stripe, stranded wire (safety ground)
Assembling And Connecting The Safety Ground Wire
WARNING
: For equipment using –(48–60) V DC power supplies, a qualified electrician must perform all
connections to DC power and to safety grounds. Do not attempt connecting to DC power or installing grounds
yourself. All electrical wiring must comply with applicable local or national codes and practices. Damage due to
servicing that is not authorized by Dell is not covered by your warranty. Read and follow all safety instructions that
came with the product.
1. Strip the insulation from the end of the green/yellow wire, exposing approximately 4.5 mm (0.175 inch) of copper
wire.
2. Using a hand-crimping tool (Tyco Electronics, 58433-3 or equivalent), crimp the ring-tongue terminal (Jeeson
Terminals Inc., R5-4SA or equivalent) to the green/yellow wire (safety ground wire).
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