OWC Mercury Elite Pro Dual Guide

MERCURY ELITE PRO DUAL
Assembly Manual & User Guide

INTRODUCTION
1.1 Minimum System Requirements............................................1
1.1.1 Apple Mac Requirements
1.1.2 PC Requirements
1.1.3 Supported Drives
1.2 Package Contents .................................................................1
1.3 About This Manual.................................................................1
1.4 Front View..............................................................................3
1.5 Rear View...............................................................................3
1.6 Usage Notes ..........................................................................4
DEVICE SETUP
2.1 Quick Start.............................................................................5
2.2 Assembly ...............................................................................5
2.3 RAID Settings ........................................................................8
2.3.1 Changing the RAID Mode
2.3.2 RAID Modes
2.4 Drive Failure...........................................................................9
2.4.1 Replacing Drives
SUPPORT RESOURCES
3.1 Formatting ...........................................................................12
3.2 Troubleshooting ...................................................................12
3.3 About Data Backup .............................................................12
3.4 Online Resources.................................................................12
3.5 Contacting Technical Support .............................................12
OWC MERCURY ELITE PRO DUAL CONTENTS
CONTENTS

OWC MERCURY ELITE PRO DUAL INTRODUCTION
1
1.1 Minimum System Requirements
1.1.1 Apple Mac Requirements
• USB 3.1 Gen 1: OS X 10.6.8 or later
• Thunderbolt™2: OS X 10.9.3 or later
1.1.2 PC Requirements
• USB 3.1 Gen 1: Windows XP or later
• Thunderbolt 2: Windows 7 or later
1.1.3 Supported Drives
• 3.5” SATA hard drives (identical model and capacity required for RAID 0 and RAID 1)
1.2 Package Contents
Not pictured: If the Mercury Elite Pro Dual was purchased without drives, a packet of screws is included.
1.3 About This Manual
The images and descriptions may vary slightly between this manual and the unit shipped. Functions and features
may change depending on the rmware version or driver version, if applicable. Please visit the product web page
for the most recent product requirements, specications, and warranty information.
Mercury Elite Pro Dual Power Supply
and cable
Thunderbolt™cable USB 3.1 Gen 1 (Standard-A
to Standard-B) cable
INTRODUCTION

OWC MERCURY ELITE PRO DUAL INTRODUCTION
2
To avoid damage, do not expose the device to temperatures outside: 41º — 107º F
(operating) or -40º — 149º F (non-operating)
Always unplug the device from the electrical outlet if there is a risk of lightning or if it will be
unused for an extended period of time. Otherwise, there is an increased risk of electrical
shock, short-circuiting or re.
Do not use the device near other electrical appliances such as televisions, radios or
speakers. Doing so may cause interference which will adversely aect the operation of the
other products.
Do not place the device near sources of magnetic interference, such as computer displays,
televisions or speakers. Magnetic interference can aect the operation and stability of hard
drives.
Do not place heavy objects on top of the device.
Protect your device from excessive exposure to dust during use or storage. Dust can build
up inside the device, increasing the risk of damage or malfunction.
Do not block any ventilation openings on the device. These help to keep the device cool
during operation. Blocking the ventilation openings may cause damage to the device and
cause an increased risk of short-circuiting or re.
Read this user guide carefully and follow the recommended steps for assembly.
Use proper anti-static precautions while installing your hard drives into this drive enclosure.
Failure to do so can cause damage to your drive mechanisms and/or the enclosure.
Do not attempt to disassemble or modify the device. To avoid any risk of electrical shock,
re, short-circuiting or dangerous emissions, never insert any metallic object into the device.
If it appears to be malfunctioning, please contact technical support.
Never expose your device to rain, or use it near water or in damp or wet conditions. Never
place objects containing liquids on the drive, as they may spill into its openings. Doing so
increases the risk of electrical shock, short-circuiting, re or personal injury.
General Use Precautions
Safety Precautions

OWC MERCURY ELITE PRO DUAL INTRODUCTION
3
1.4 Front View
1. Power LED — emits a solid blue light when the
Mercury Elite Pro Dual is powered on.
2. LEDs 1 & 2 — these LEDs represent the two drives
inside the Mercury Elite Pro Dual. During normal
activity, each of these LEDs will blink green when
the corresponding drive is accessed. If one of the
drives in the enclosure fails, or if the drive bay is
empty, the corresponding LED will turn solid red.
3. Rebuild — If the Mercury Elite Pro Dual is set up
as a RAID 1 and one of the hard drives is being
rebuilt, this LED will blink orange during the rebuild
process.
1.5 Rear View
1. USB 3.1 Gen 1 port — attach the included USB
3.1 Gen 1 (Standard-A to Standard-B) cable to this
port.
2. RAID Dial & Set button— set the RAID mode by
using these items.
3. Thunderbolt ports — attach the included
Thunderbolt cable to one of these ports. Connect
a daisy-chained Thunderbolt device to the other
port as needed.
4. DC IN — connect the included power supply here.
5. Kensington® Security Slot — connect a security
tether here.
123
1
2
3
45

OWC MERCURY ELITE PRO DUAL INTRODUCTION
4
1.6 Usage Notes
• Use only one interface (USB 3.1 Gen 1 or Thunderbolt) at a time.
• Identical drives (model, capacity, rmware) are required for RAID 0 and RAID 1 congurations.
• During normal drive activity the Drive LEDs will display as solid green while the Activity LED blinks orange.
• If a drive fails or is not connected properly, the corresponding LED will display as solid red.
• If you are building a new array or if you have replaced a drive in a RAID 1 setup and are rebuilding the
array, the Activity LED will pulse orange.
• For the safe removal of your drive and to ensure that no data is lost, always eject or unmount the
corresponding disk(s) from your operating system before powering o. You can use the methods
described below to safely unmount your disk(s).
OS X :
• Drag the icon for the disk you wish to unmount to the trash can; OR
• Right-click the disk icon on the desktop, then click “Eject”; OR
• Highlight the disk on your Desktop and press Command-E.
Windows:
1. Go to the System Tray (located in the lower right corner of your screen). Click on the “Eject”
icon (a small green arrow over a hardware image).
2. A message will appear, detailing the devices that the “Eject” icon controls, i.e., “Safely remove...” Click on
this prompt.
3. You will then see a message that says, “Safe to Remove Hardware.” It is now safe to disconnect
the Mercury Elite Pro Dual from the computer.

OWC MERCURY ELITE PRO DUAL DEVICE SETUP
5
2.1 Quick Start
Follow the steps below to use the OWC Drive Guide utility to format your Mercury Elite Pro Dual for Mac (OS X
10.6 and later) or Windows (XP and later). If you installed your own drives, please use the formatting method you
are most familiar with or check Section 3.1 for a link to our online formatting tips.
1. Power on the Mercury Elite Pro Dual and plug it into to your computer using the proper data cable. If you prefer
to use a dierent formatting utility, do so at this time and skip the rest of these steps.
2. The disk will mount and your operating system will display it as “OWC SETUP”. Open the disk icon to view its
contents.
3. Double-click the OWC Drive Guide application.
4. Follow the simple on-screen instructions to complete the formatting process. Once the formatting is nished
the drive is ready to use.
2.2 Assembly
NOTE: these assembly instructions are written for users who purchased the Mercury Elite Pro Dual as an empty
enclosure. The instructions show how to open the enclosure in order to install drives. If you purchased the
Mercury Elite Pro Dual with drives already installed, opening the enclosure before the expiration of the original
warranty will VOID the warranty. If you wish to remove or replace the drives after the expiration of the original
warranty, you may do so at that time. You should start with Step 9 in that case and work backwards.
1. Remove the Mercury Elite Pro Dual from its packaging,
then set the enclosure on its side. Use a Phillips PH2
driver to remove the two screws shown at right.
2. Slide the inner chassis out the front of the outer
enclosure, as shown at left. Start by pushing on
the back cover, then grip the front grill and pull the
chassis the rest of the way.
DEVICE SETUP

OWC MERCURY ELITE PRO DUAL DEVICE SETUP
6
3. Remove the packet of screws from the inner chassis
and set them aside; they will be used in upcoming
steps.
4. IMPORTANT: before installing the drives, note that each
SATA port on the blue circuit board is accompanied
by a label. These labels are printed on the board and
are located at the base of the two red SATA cables.
The ‘Drive A’ cable corresponds to LED 1 on the front
cover. The ‘Drive B’ cable corresponds to LED 2. This
is important when replacing a failed drive or checking
a drive’s connection.
To continue with the installation, carefully set the rst
hard drive into the inner chassis so that the edge with the SATA ports sits just to the right of the cable connectors
on the circuit board. Connect one set of data and power cables to the corresponding ports on the drive.
5. Set the second hard drive into the inner chassis so it is
aligned above the rst drive. Connect the second set
of data and power cables to the corresponding ports
on the drive. The cables may need to twist or bend
a modest amount; this is OK as long as you do not
crimp the cables and as long as none of the cables
protrude from the back plate once connected.
6. Using eight of the larger screws from the packet
removed in Step 3, fasten the inner chassis to the
hard drives. There are four screw holes on each side
of the inner chassis; you may need to move each
drive slightly to align its screwholes with the holes on
the inner chassis.

OWC MERCURY ELITE PRO DUAL DEVICE SETUP
7
7. To determine the correct orientation of the outer
enclosure relative to the inner chassis, turn the outer
enclosure on its side and look at the bottom. As
shown above, the screw holes at the front of the
outer enclosure are close to the silicone feet. The
screw holes at the rear of the outer enclosure are
farther away from the silicone feet.
8. Once you know the correct orientation from Step 7,
slide the inner chassis back into the outer enclosure
as shown.
9. Once the front grill of the inner chassis sits ush with the
edge of the outer enclosure, turn the device on its side
again. The screw holes in the outer enclosure should
line up with the screw holes in the inner chassis. Use
the four smaller screws to fasten the inner chassis to
the outer enclosure, shown above.
This completes the assembly process.
REAR FRONT

OWC MERCURY ELITE PRO DUAL DEVICE SETUP
8
2.3 RAID Settings
2.3.1 Changing the RAID Mode
The RAID mode is controlled by a dial on the rear of the unit, as shown below-left. The dial has four positions,
each labeled with a dierent RAID mode. To change the RAID mode, follow the simple steps below.
Adjust the RAID dial so that the arrow is pointing at the desired RAID mode. Each time the arrow is aligned
with a new mode, you will feel a slight click. A small athead screwdriver works the best to adjust the dial.
When starting from a powered-on state, rst unmount the disk, then
rotate the RAID dial to the desired mode and hold down the SET button
for 3 seconds. The LEDs on the front will blink for a brief time; once the
blinking stops the new array has been built. You can access and format
the disk in the OS at this time.
When starting from a powered-o state, rotate the dial on the back of
the enclosure to the desired RAID mode, then power on the Mercury
Elite Pro Dual and immediately press the SET button for three seconds. The LEDs on the front will blink; once
the blinking stops the new array has been built. You can access and format the disk in the OS at this time.
2.3.2 RAID Modes
RAID 0 “Drive Striping” Mode:
The two drives show up as a single large disk with a size equal to the combined capacities of both drives.
RAID 0 is used when speed is the primary objective; it does not provide data redundancy for protection.
The reading and writing of data les is spread across both drives to gain speed by distributing the workload.
This allows for the fastest data transfer rates, but if one drive fails the whole array becomes corrupted. The
data will be lost.
RAID 1 “Drive Mirroring” Mode:
The two drives show up as a single disk with a size equal to the capacity of a single drive from the array.
RAID 1 copies (or “mirrors”) the data from the rst drive to the second drive. This is useful when reliability
and redundancy are more important than capacity or maximum speed. When one drive fails, it can be
replaced and the data can be rebuilt automatically from the other functioning drive. See Section 2.4 for
more details on the drive replacement and rebuild process.
Warning Changing the RAID mode will destroy the data on the drives. Be sure to back up your data rst!
See Section 3.4 for information on proper backup strategies.
Note Changing the RAID mode for the Mercury Elite Pro Dual requires an active USB or Thunderbolt
connection.
Warning Drives of identical model and capacity are required for RAID 0 and RAID 1. Always maintain a full
and separate backup of your RAID disks, especially RAID 0 disks.

OWC MERCURY ELITE PRO DUAL DEVICE SETUP
9
Span Mode:
Both drives show up as a single large disk, but one which functions dierently than RAID 0. The total size
will depend on the drives installed; unlike RAID 0 or RAID 1 you can use drives of dierent capacities. A
Span is an array (but not a RAID) in which the data is written sequentially across the drives. When one drive
becomes full, subsequent data is written to the second drive. This combines the capacities of the drives,
but it does not provide any performance or data redundancy benets.
Independent Drive Mode
Each drive will appear individually without being combined. If you are using drives of diering capacity and
model, or if you are using only one drive, this is the mode to use.
2.4 Drive Failure
If one of the drives fails, the corresponding drive LED will turn solid red. If the Mercury Elite Pro Dual was congured
as a RAID 0 or Span, the data on the array is lost and the disk is no longer usable. In a span, only the data stored
on the failed drive is lost, although data recovery software will be required to retrieve the data from the other drive.
If the drives were congured independently, then the data on the drive that did not fail will remain intact.
2.4.1 Replacing Drives
If the Mercury Elite Pro Dual is set up as a RAID 1, a drive that has failed can be replaced. The data will remain
accessible via the functioning drive until the array is rebuilt with a new drive. If the enclosure was purchased
with drives and it is still under warranty, contact OWC technical support for assistance (see Section 3.5). If
the unit is outside its warranty or was purchased without drives, follow the assembly instructions in Section
2.2 to access and replace the failed drive.
If the Drive 1 LED is solid red, the failed drive is the one connected to the data and power cable labeled as
Port 1 on the printed circuit board (Section 2.2 Step 4). If the Drive 2 LED is solid red, the failed drive is the
one connected to the data and power cable labeled Port 2.
Once the drive has been replaced, if the Mercury Elite Pro Dual is congured as a RAID 1, the array will
automatically begin to rebuild when the enclosure is powered on. This process may take several hours to
more than a day, based on the capacity of the drives. During the rebuild process, the LED for both drives will
blink green. The Rebuild LED will blink orange.
If possible, leave the Mercury Elite Pro Dual powered on during the entire rebuild process; if power is
interrupted (or the computer sleeps), the unit will continue rebuilding automatically when power is restored.
Once the rebuild process is complete, the rebuild LED will turn o and the LED for the rebuilt drive will
resume normal activity. See Section 1.6 for more information on the behavior of the LEDs.
Note
The Mercury Elite Pro Dual needs an active data signal to remain powered on. If it is disconnected
from the computer, or if the computer goes to sleep or turns o, the device will power o.
To minimize the total rebuild time, it is recommended to keep the device connected to the
computer (with the computer powered on), and disable any hard drive sleep settings on the
computer for the duration of the rebuild process.
Note A failed drive must be replaced with an identical drive (model, capacity, rmware).

OWC MERCURY ELITE PRO DUAL SUPPORT RESOURCES
10
3.1 Fo r ma t ti ng
For additional formatting information, including instructions on how to format your Mercury Elite Pro Dual for Mac
or Windows, go to: www.owcdigital.com/format
3.2 Troubleshooting
Begin by verifying that the power cable is connected to the Mercury Elite Pro Dual and to a power source. If the
power cable is connected to a power strip, make sure that the power strip switch is in the ON position. Next,
verify that both ends of the data cable are properly plugged into the computer and the Mercury Elite Pro Dual,
respectively.
If you are still having trouble, try connecting a dierent type of data cable and see if the Mercury Elite Pro Dual
works properly; you can also connect the device to a dierent computer or use dierent cables of the same type.
If one of the drive LEDs (Drive 1 or Drive 2) is solid red, then that drive has failed or is missing. If you purchased the
Mercury Elite Pro Dual as an empty enclosure, or the enclosure shipped with drives installed but is past the three
year warranty period, unmount the disk from the OS, power o, then check the cables connected to drive and
enclosure. See Section 2.4 if you are sure the drive has failed. If the Mercury Elite Pro Dual is congured as a RAID
1 and the rebuild LED is blinking, simply wait for the rebuild process to complete. If the rebuild LED is still blinking
after more than 48 hours, or if you still need assistance for other reasons, Section 3.5 provides information for
contacting technical support.
3.3 About Data Backup
To ensure that your les are protected and to prevent data loss, we strongly suggest that you keep two copies
of your data: one copy on your Mercury Elite Pro Dual and a second copy on either your internal drive or another
storage medium, such as an optical backup, or on another external storage unit. Any data loss or corruption while
using the Mercury Elite Pro Dual is the sole responsibility of the user, and under no circumstances may OWC,
its parents, partners, aliates, ocers, employees, or agents be held liable for loss of the use of data including
compensation of any kind or recovery of the data.
3.4 Online Resources
To access our online knowledge base, which includes topics like migrating your data from an old drive to a new
one, please visit: www.owcdigital.com/faq
3.5 Contacting Technical Support
8am - 5pm (CT) Monday - Friday
SUPPORT RESOURCES
Live chat is available during business hours:
www.owcdigital.com/support
Email support is available at:
www.owcdigital.com/support
Contact us by phone at:
[phone] (North America only)
[phone] (International)

Copyright 2016 OWC. All Rights Reserved.
OWC’s Limited Warranty is not transferable and subject to limitations. OWCMANMEPDTB2U3R1 11/08/16 DM
Changes:
The material in this document is for information purposes only and subject to change without notice. While
reasonable eorts have been made in the preparation of this document to assure its accuracy, OWC, its
parent, partners, aliates, ocers, employees, and agents assume no liability resulting from errors or
omissions in this document, or from the use of the information contained herein. OWC reserves the right
to make changes or revisions in the product design or the product manual without reservation and without
obligation to notify any person of such revisions and changes.
FCC Statement:
Warning! Modications not authorized by the manufacturer may void the user’s authority to operate this
device.
NOTE: This equipment has been tested and found to comply with the limits for a Class B digital device,
pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against
harmful interference in a residential installation. This equipment generates, uses and can radiate radio
frequency energy and, if not installed and used in accordance with the instructions, may cause harmful
interference to radio communications. However, there is no guarantee that interference will not occur in a
particular installation. If this equipment does cause harmful interference with radio or television reception,
which can be determined by turning the equipment o and on, the user is encouraged to try to correct the
interference by one or more of the following measures:
• Reorient or relocate the receiving antenna.
• Increase the separation between the equipment and receiver.
• Connect the equipment to an outlet on a circuit dierent from that to which the receiver is connected.
Warranty:
The Mercury Elite Pro Dual has a 3 Year OWC Limited Warranty if it was bundled with drives. Mercury Elite
Pro Dual enclosures that do not ship with drives have a 1 Year OWC Limited Warranty. Please visit the web
site for details.
Copyrights and Trademarks:
No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by
any means, electronic, mechanical, photocopying, recording or otherwise, without the prior written consent
of OWC.
© 2016 OWC. All rights reserved.
OWC is trademark of New Concepts Development Corporation, registered in the U.S. Patent and Trademark
Oce and/or in Canada. The OWC logo is a trademark of New Concepts Development Corporation. Apple,
Mac, and OS X are trademarks of Apple Inc., registered in the United States and/or other countries. Windows
and Windows Vista are either registered trademarks or trademarks of Microsoft Corporation in the United
States and/or other countries. Other marks may be the trademark or registered trademark property of their
owners.