natus Xltek Trex HD Troubleshooting guide

Trex™HD Monitoring Amplifier
User & Service Manual

Publisher’s Notice
019694 Rev 03
Trex HD Monitoring Amplifier User & Service Manual
Natus Medical Incorporated
DBA Excel-Tech Ltd. (XLTEK)
2568 Bristol Circle
Oakville, Ontario, L6H 5S1 Canada
Tel: [phone] or Fax: [phone]
Toll Free (US & Canada): 800-303-0306
Technical Support Email: [e-mail]
Website: www.natus.com
Copyright © 2016 by Natus Neurology Incorporated.
All rights reserved. This manual contains proprietary information, which is protected by copyright and may not be copied in
whole or in part except with the prior written permission of Natus Neurology Incorporated. The copyright and the foregoing
restrictions on the copyright use extend to all media in which this information is preserved.
This copy of the User Manual shall be used only in accordance with the conditions of sale of Natus Neurology
Incorporated or its distributors. Natus Neurology Incorporated makes no representations or warranties of any kind
whatsoever with respect to this document. Natus Neurology Incorporated disclaims all liabilities for loss or damage arising
out of the possession, sale, or use of this document.

User & Service Manual Trex™ HD Monitoring Amplifier
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Table of Contents
1. Introduction .................................................................................................................. 5
1.1. Intended Use...............................................................................................................................6
1.2. Using the Manual........................................................................................................................6
1.3. Manual Conventions ..................................................................................................................6
2. Safety and Standards Conformity............................................................................... 7
2.1. Safety and Standards Conformity for Natus Trex HD.............................................................7
2.1.1. Standards of Compliance and Normative References........................................................7
2.1.2. Declaration of Compliance for IEC 60601-1-2....................................................................9
2.1.3. Electromagnetic Immunity (EMI) Information –FCC........................................................13
3. Warnings and Cautions...............................................................................................14
3.1. General Warnings.....................................................................................................................14
3.2. Electrical Warnings and Cautions ..........................................................................................16
3.3. Electrostatic Discharge (ESD) Precautions:..........................................................................17
3.4. Wireless Option Warnings and Cautions...............................................................................17
3.5. Patient Environment Warnings and Cautions .......................................................................17
3.6. Pulse Oximeter Warnings........................................................................................................18
3.7. Pulse Oximeter Sensor Warnings...........................................................................................20
3.8. Transportation Warnings.........................................................................................................21
3.9. Conducted Immunity Warnings ..............................................................................................21
4. Procedures and Warnings ..........................................................................................22
4.1. Electrostatic Discharge (ESD) Handling Procedures and Warnings ..................................22
4.2. Conducted Immunity Procedures and Warnings..................................................................23
5. Description of Symbols...............................................................................................24
6. Specifications..............................................................................................................26
7. Product Images ...........................................................................................................28
7.1. Front View .................................................................................................................................28
7.2. Rear View...................................................................................................................................29
8. Unpacking....................................................................................................................30
8.1. Trex HD Monitoring Package Items........................................................................................30
8.2. Optional Accessories...............................................................................................................31
9. Setting Up ....................................................................................................................32
9.1. Getting Started..........................................................................................................................32
9.1.1. Placement of the Operator and Patient ............................................................................32
9.1.2. Beginning a study..............................................................................................................32
9.1.3. Monitoring an ongoing ambulatory study..........................................................................33
9.1.4. Backfill and reviewing an ongoing ambulatory study........................................................33
9.1.5. Powering Down the System..............................................................................................34
9.2. Adding the Trex HD unit to a belt or a lanyard......................................................................34
9.2.1. Belt Setup..........................................................................................................................34
9.2.2. Lanyard Setup...................................................................................................................35
9.3. Setting up Trex HD Amplifier for a non-Video Study............................................................37
9.4. Testing the Trex HD Amplifier.................................................................................................37
9.4.1. Calibration and Verification...............................................................................................37
9.4.2. Channel Test.....................................................................................................................38
9.4.3. Impedance Check .............................................................................................................39
10. Nonin Xpod Pulse Oximeter .......................................................................................40

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10.1. No Implied License.................................................................................................................40
10.2. Indications for Use .................................................................................................................40
10.3. Accessories.............................................................................................................................40
10.3.1. Cables.............................................................................................................................40
10.3.2. Available Oximetry Sensors............................................................................................41
10.4. Measurements ........................................................................................................................42
10.5. Displayed Ranges...................................................................................................................42
11. Guaranteeing Sufficient Battery Power .....................................................................43
11.1. Battery Power with AA Batteries (only)................................................................................43
11.2. Battery Power with AA Batteries and Power Pack..............................................................44
12. External Power Pack...................................................................................................45
12.1. Power Pack Symbols .............................................................................................................45
12.2. External Power Pack Specifications.....................................................................................45
12.3. External Power Pack Warnings and Cautions.....................................................................46
12.4. Using the External Power Pack Kit.......................................................................................47
12.5. External Power Pack and Charging Details.........................................................................48
12.5.1. External Power Pack LED Indicators..............................................................................48
12.6. Charging the External Power Pack.......................................................................................49
12.7. Disconnecting the External Power Pack..............................................................................49
12.8. Storing the External Power Pack ..........................................................................................49
12.9. Troubleshooting the External Power Pack ..........................................................................49
13. How to Disable Channels and Set Frequency...........................................................51
14. Maintenance, Cleaning, & Disposal............................................................................52
14.1. Recommendations .................................................................................................................52
14.2. Disposal...................................................................................................................................53
14.3. Expected Service Life ............................................................................................................53
15. Troubleshooting..........................................................................................................54
16. Getting Help.................................................................................................................55
17. EEG and Sleep Accessories.......................................................................................56
18. Index.............................................................................................................................57

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1. Introduction
The Natus Trex HD amplifier for ambulatory monitoring provides you with maximum reliability and
performance for clinical electroencephalographic (EEG) and polysomnographic (PSG) recordings. It is
designed to be used with Natus SleepWorks™or NeuroWorks®v8.1.x software to assist with diagnosis.
Trex HD offers these features:
Connects to Natus computer
24 referential AC inputs
4 differential AC inputs
4 non-isolated DC inputs for connection to Natus patient-worn transducers
Internal memory for up to 96hr of EEG recording
Battery powered by two AA alkaline batteries and an optional power pack providing up to 72
hours of continuous recording
Bluetooth module for live monitoring during ambulatory recording
Ability to backfill and review an ongoing ambulatory study
Isolated serial port
Patient-event button
Please read and follow all instructions that are provided with the system.
WARNING: We strongly recommend you read and follow the Safety and Warnings and
Cautions section of this manual before operating this amplifier.
WARNINGS:
The NeuroWorks 8.1.1 software for Trex HD monitoring is strictly for use with the Trex HD
monitoring amplifier. It does not support any other Natus amplifiers.
This Trex HD monitoring amplifier can only be used with the NeuroWorks 8.1.1 software for
Trex HD monitoring. This software comes installed on a qualified tablet computer. Do not load
the software on to any other computer model.
The Trex HD is intended to be used by either trained medical professionals or someone instructed by a
trained medical professional. It is designed for use in clinical environments such as hospital rooms,
epilepsy monitoring units, intensive care units, and operating rooms. It can be used with patients of all
ages, but is not designed for fetal use.
The Trex HD is supplied with a standard label displaying markings for EEG studies; for convenience
when performing Sleep studies, the user may apply the “Trex HD Sleep” label with markings designed for
Sleep studies (provided).
NOTE: The functionality of the Trex HD is not affected by the label and all instructions,
warnings and cautions described in this manual still apply.
WARNING: The Trex HD should NOT be used as an apnea monitor.

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1.1. Intended Use
The Trex HD is an Electroencephalograph intended to be used to acquire, display, store and archive
electroencephalographic signals, intended for electroencephalographic (EEG) or level 1-2
polysomnographic (PSG) recordings. The Trex HD amplifier is designed to be used with Natus
NeuroWorks or Natus SleepWorks software.
1.2. Using the Manual
This manual provides basic information and instructions that will enable you to set up and operate the
Trex HD amplifier. When going through the procedures, we recommend that you read the whole section
first, before starting the sequence. In order to achieve the optimal use, Trex HD must be installed and
operated according to the instructions provided in this user manual. Please follow all instructions
carefully.
NOTE: In addition to reading this manual, we encourage you to explore the online Help of the
software to enable you to take advantage of everything that Natus has designed the Trex HD
amplifier to do. More detailed instructions relating to the operation and customization of the
system are provided in the online Help.
1.3. Manual Conventions
Various symbols and typographical conventions are used throughout the manual. The following table
illustrates them and describes their meanings and functions.
Symbol/
Convention
Description/Function
This symbol denotes a warning or important information that should not be
missed. Read all warnings and cautions carefully before starting the system for
the first time.
This symbol indicates a note that contains important supplemental information.
Bold
Names of control keys, function keys, options, and labels are shown in bold. Bold
text is also used to emphasize important names or ideas.
Italic
Italic text is used for captions.

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2. Safety and Standards Conformity
2.1. Safety and Standards Conformity for Natus Trex HD
2.1.1. Standards of Compliance and Normative References
Electroencephalograph system, model Trex HD; rated two AA 1.5V batteries, 0.065A, 0.170W.
1. Type of protection against electric shock: Internally Powered Equipment
2. Degree of protection against electric shock: Type BF
3. Degree of protection against ingress of water: IPX0
4. Mode of operation: Continuous
5. Environmental Conditions: Normal: 5-40°C, 15-93% rH, 700-1060hPa
The essential performance of the Trex HD amplifier system is defined in the particular standards IEC
60601-2-26 and ISO 80601-2-61. It is EEG equipment that incorporates a pulse oximeter without an
alarm.
The Trex HD and its accessories have been designed to comply with the following national and
international standards.
Table 1 - Safety Standard of Compliance and Normative
CAN/CSA-C22.2 No. 60601-1: 08(R2013) +
C2:2011
ANSI/AAMI ES60601-1:2005/(R)2012 +
C1:2009/(R)2012 and A2:2010/(R)2012
IEC 60601-1:2005 + C1:2006 and C2:2007,
Third Edition
CENELEC EN 60601-1:2006 + A1:2013
Medical electrical equipment –Part 1: General
requirements for basic safety and essential performance
CAN/CSA C22.2 No 601.1-M90
UL 60601-1:2003
IEC 60601-1:1988 + A1:1991 + A2:1995
Medical Electrical Equipment Part 1: General
Requirements for Safety
IEC 60601-2-26:2012, Edition 3
CENELEC EN 60601-2-26 L2003, Edition 2
CAN/CSA C22.2 No. 60601-2-26-04
IEC 60601-2-26: 2002
Medical Electrical Equipment - Part 2-26: Particular
Requirements for the Safety of Electroencephalographs
CAN/CSA C22.2 No. 60601-1-4-02
IEC 60601-1-4: 1996 + A1: 1999
Medical Electrical Equipment - Part 1-4: General
Requirements for Safety - Collateral Standard:
Programmable Electrical Medical Systems
EN ISO 80601-2-61:2011, Edition 1
Medical electrical equipment –Part 2-61: Particular
requirements for basic safety and essential performance
of pulse oximeter equipment
IEC 60601-1-6:2010, Edition 3.0
CAN/CSA C22.2 No. 60601-1-6-05
IEC 60601-1-6: 2004
Medical Electrical Equipment - Part 1-6: General
requirements for safety - Collateral Standard: Usability

Trex™ HD Monitoring Amplifier User & Service Manual
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IEC 62366:2007, Edition 1.0
Medical devices –Application of usability engineering to
medical devices
IEC 60601-1-11:2010, Edition 1.0
Medical electrical equipment –Part 1-11: General
requirements for basic safety and essential performance
–Collateral Standard: Requirements for medical electrical
equipment and medical electrical systems used in the
home healthcare environment
CAN/CSA C22.2 No. 60601-1-1-02
IEC 60601-1-1: 2000
Medical Electrical Equipment - Part 1-1: General
Requirements for Safety - Collateral Standard: Safety
Requirements for Medical Electrical Systems
Table 2 - EMC Standard of Compliance and Normative References
IEC 60601-1-2:2007, Edition 3.0
IEC 60601-1-2:2001 +A1:2004 / EN 60601-
1-2:2001 +A1:2006
Medical Electrical Equipment Part 1-2:General
Requirements for Safety - Collateral Standard:
Electromagnetic Compatibility - Requirements and Tests
IEC 61000-4-2:2008 / EN 61000-4-2:2009
Electromagnetic Compatibility (EMC) Part 4-2: Testing
and Measurement Techniques - Electrostatic Discharge
Immunity Test
IEC 61000-4-3:2006 +A1:2007 +A2:2010 /
EN 61000-4-3:2006 +A1:2008 +A2:2010
Electromagnetic Compatibility (EMC) Part 4-3: Testing
and Measurement Techniques - Radiated, Radio-
frequency, Electromagnetic Field Immunity Test
IEC 61000-4-4:2012, ed 3.0
IEC 61000-4-4:2004 +A1:2010 / EN 61000-
4-4:2004 +A1:2010
Electromagnetic Compatibility (EMC) Part 4-4: Testing
and Measurement Techniques - Electrical Fast
Transient/Burst Immunity Test
IEC 61000-4-5:2014, ed 3.0
IEC 61000-4-5:2005 / EN 61000-4-5:2006
Electromagnetic Compatibility (EMC) Part 4-5: Testing
and Measurement Techniques - Surge Immunity Test
IEC 61000-4-6:2008 / EN 61000-4-6:2009
Electromagnetic Compatibility (EMC) Part 4-6: Testing
and Measurement Techniques - Immunity to Conducted
Disturbances, Induced by Radio-frequency Fields
IEC 61000-4-8:2009 / EN 61000-4-8:2010
Electromagnetic Compatibility (EMC) Part 4-8: Testing
and Measurement Techniques - Power Frequency
Magnetic Field Immunity Test
IEC 61000-4-11:2004 / EN 61000-4-11:2004
Electromagnetic Compatibility (EMC) Part 4-11: Testing
and Measurement Techniques - Voltage Dips, Short
Interruptions and Voltage Variations Immunity Tests
IEC 61000-3-2:2014, ed 4.0
IEC 61000-3-2:2005 +A1:2008 +A2:2009 /
EN 61000-3-2:2006 +A1:2009 +A2:2009
Electromagnetic Compatibility (EMC) Part 3-2: Limits -
Limits for Harmonic Current Emissions
IEC 61000-3-3:2013, ed 3.0
IEC 61000-3-3:2008 / EN 61000-3-3:2008
Electromagnetic Compatibility (EMC) Part 3-3: Limits -
Limitation of Voltage Changes, Voltage Fluctuations and
Flicker in Public Low-voltage Supply Systems

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CISPR 11:2009 +A1:2010 / EN 55011:2009
+A1:2010
Industrial, Scientific and Medical (ISM) Radio-Frequency
Equipment - Electromagnetic Disturbance Characteristics
- Limits and Methods of Measurement
2.1.2. Declaration of Compliance for IEC 60601-1-2
Table 1 - Electromagnetic Emissions
1
Guidance and Manufacturer’s Declaration – Electromagnetic Emissions
The Trex HD is intended for use in the electromagnetic environment specified below. The customer or the
Trex HD should assure that it is used in such an environment.
Emissions Test
Compliance
Electromagnetic Environment –Guidance
RF emissions
CISPR 11
Group 1
The Trex HD uses RF energy only for its internal
function. Therefore, its RF emissions are very low and
are not likely to cause any interference in nearby
electronic equipment.
RF emissions
CISPR 11
Class B
The Trex HD is suitable for use in all establishments,
including domestic establishments and those directly
connected to public low voltage power supply network
that supplies buildings used for domestic purposes.
Harmonic emissions
IEC 61000-3-2
Class A
Voltage fluctuations/
flicker emissions
IEC 61000-3-3
Complies
1
The conducted, harmonic, and flicker emissions testing was only performed on the mains-powered
camcorder and mains-powered PC when providing power to the Trex HD amplifier via USB connection.
This testing was not performed on the Trex HD amplifier in isolation because it is a battery-powered
device.

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Table 2 - Electromagnetic Immunity
2
Guidance and Manufacturer’s Declaration – Electromagnetic Immunity
The Trex HD is intended for use in the electromagnetic environment specified below. The customer or the
user of the Trex HD should assure that it is used in such an environment.
Immunity Test
IEC 60601
Test Level
Compliance
Level
Electromagnetic Environment -
Guidance
Electrostatic
Discharge (ESD)
IEC 61000-4-2
±6 kV contact
±8 kV air
±6 kV contact
±8 kV air
Floors should be wood, concrete or
ceramic tile. If floors are covered with
synthetic material, the relative
humidity should be at least 30%.
Electrostatic fast
transient/burst
IEC 61000-4-4
±2 kV for power
supply lines
±1 kV for
input/output lines
±2 kV for power
supply lines
N/A –lines <3m
Mains power quality should be that of
a typical commercial or hospital
environment.
Surge
IEC 61000-4-5
±1 kV Line to Line
±2 kV Line to
Earth
±1 kV Line to Line
±2 kV Line to
Earth
Mains power quality should be that of
a typical commercial or hospital
environment.
Voltage dips, short
interruptions and
voltage variations on
power supply input
lines
IEC 61000-4-11
<5% UT
(>95% dip in UT)
for 0.5 cycle
40% UT
(60% dip in UT)
for 5 cycles
70% UT
(30% dip in UT)
for 25 cycles
<5% UT
(>95% dip in UT)
for 5 sec
<5% UT
(>95% dip of UT)
for 0.5 cycle
40% UT
(>60% dip of UT)
for 5 cycles
70% UT
(>30% dip of UT)
for 25 cycles
<5% UT
(>95% dip of UT)
for 5 sec
Mains power quality should be that of
a typical commercial or hospital
environment. If the user of the Trex
HD requires continued operation
during power mains interruption, it is
recommended that the Trex HD to be
powered from a suitable
uninterruptible power supply or a
battery.
Power frequency
(50/60 Hz) magnetic
field
IEC 61000-4-8
3 A/m
3 A/m
Power frequency magnetic fields
should be at levels characteristic of a
typical location in a typical commercial
or hospital environment.
NOTE: UT is the AC supply voltage prior to application of the test level.
2
The electrostatic fast transient, surge, and voltage dips testing was only performed on the mains-
powered camcorder and mains-powered PC when providing power to the Trex HD amplifier via USB
connection. This testing was not performed on the Trex HD amplifier in isolation because it is a battery-
powered device.

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Table 3 - Electromagnetic Immunity –for EQUIPMENT and SYSTEMS that are not LIFE-
SUPPORTING
Guidance and Manufacturer’s Declaration – Electromagnetic Immunity
The Trex HD is intended for use in the electromagnetic environment specified below. The customer or the
user of the Trex HD should assure that it is used in such an environment.
Immunity test
Test Level
IEC60601-1-2
Compliance
Level
Electromagnetic Environment - Guidance
Conducted RF
IEC 61000-4-6
Radiated RF IEC
61000-4-3
3 Vrms
150 kHz to 80
MHz
3 V/m
80 MHz to 2.5
GHz
3 Vrms
3 V/m
Portable and mobile RF communications equipment
should be used no closer to any part of the Trex HD,
including cables, than the recommended separation
distance calculated from the equation applicable to
the frequency of the transmitter.
Recommended separation distance:
d=1.2 ×√P 150kHz to 80MHz
d=1.2 ×√P 80MHz to 800MHz
d=2.3 ×√P 800MHz to 2.5GHz
Where P is the maximum output power rating of the
transmitter in watts (W) according to the transmitter
manufacturer and dis the recommended separation
distance in meters (m).
Field strengths from fixed RF transmitters, as
determined by an electromagnetic Site survey3,
should be less than the compliance level in each
frequency range4.
Interference may occur in the vicinity of equipment
marked with the following symbol: .
Note 1: At 80 MHz and 800 MHz, the higher frequency range applies.
Note 2: These guidelines may not apply in all situations. Electromagnetic propagation is affected by
absorption and reflection from structures, objects and people.
3
Field strengths from fixed transmitters such as base stations for radio (cellular/cordless) telephones and
land mobile radios, amateur radio, AM and FM radio broadcast and TV broadcast cannot be predicted
theoretically with accuracy. To assess the electromagnetic environment due to fixed RF transmitters, an
electromagnetic site survey should be considered. If the measured field strength in the location in which
the Trex HD+ is used exceeds the applicable RF compliance level above, the Trex HD should be
observed to verify normal operation. If abnormal performance is observed, additional measures may be
necessary, such as re-orienting or relocating the Trex HD.
4
Over the frequency range 150 kHz to 80 MHz, field strengths should be less than 3 V/m.

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Table 4 - Recommended Separation Distances
Recommended separation distances between portable and mobile RF communications equipment
and the Trex HD
The Trex HD is intended for use in the electromagnetic in which radiated RF disturbances are controlled.
The customer or user of the Trex HD can help prevent electromagnetic interference by maintaining a
minimum distance between portable and mobile RF communications equipment (transmitters) and the
Trex HD as recommended below, according to the maximum output power of the communications
equipment.
Rated maximum
output power of
transmitter (W)
Separation distance according to the frequency of transmitter (m)
from 150kHz to
80MHz
d= 1.2 x √P
from 80MHz to
800MHz
d= 1.2 x √P
from 800MHz to
2.5GHz
d= 2.3 x √P
0.01
0.12
0.12
0.23
0.1
0.38
0.38
0.73
1
1.2
1.2
2.3
10
3.8
3.8
7.3
100
12
12
23
For the transmitters rated at a maximum output power not listed above, the recommended separation
distance d in meters (m) can be estimated using the equation applicable to the frequency of the
transmitter, where P is the maximum output power rating of the transmitter in Watts (W) according to the
transmitter manufacturer.
Note 1: At 80 MHz and 800 MHz, the separation distance for the higher frequency range applies.
Note 2: These guidelines may not apply in all situations. Electromagnetic propagation is affected by
absorption and reflection from structures, objects and people

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2.1.3. Electromagnetic Immunity (EMI) Information –FCC
NOTE: This equipment has been tested and found to comply with the limits for Class B digital
devices, 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 instruction manual, 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 to radio or television
reception, which can be determined by turning the equipment off and on, the user is
encouraged to try to correct the interference by one of more of the following measures:
Reorient or relocate the receiving antenna
Increase the separation between the equipment and receiver
Connect the equipment into an outlet on a circuit different from that to which the
receiver is connected.
Consult the dealer or an experienced radio/TV technician for help.
WARNING: Changes or modifications not expressly approved by Natus may void the user’s
authority to operate the equipment.

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3. Warnings and Cautions
3.1. General Warnings
NOTE: It is recommended that all data be stored using redundant storage capabilities. This
can help to minimize data loss in the event of a failure of the primary drive.
Proper use of this device depends on the careful reading of all instructions and labels that
come with or on the system. Inaccurate measurements may be caused by incorrect
application or use.
The amplifier is classified as an IPX0 –ordinary degree of protection against ingress of
water according to IEC 529. The amplifier is classified as a class II device according to
IEC601-1.
The computer used with a Trex HD amplifier must either be approved by Natus and
supplied as part of an IEC 601 approved system, or it must be approved to IEC 950 or
similar and kept outside of the patient environment, (that is, at least 1.5 meters from the
patient laterally and not within a height of 2.5 meters from the floor in the area occupied by
the patient).
Only use the Trex HD in conjunction with approved devices and accessories.
Use of cables other than those specified or sold by the manufacturer on the equipment, may
result in increased emissions or decreased immunity of the equipment and may cause the
system to be non-compliant with the requirements of IEC 60601-1-2:2007.
Nonin 8000J pulse oximeter sensors used with the Trex HD amplifier are in compliance with
the requirements of 6.1 and 6.2 when used with the Natus Nonin LP Trex Cable (p/n
010382).
To ensure the validity of signals, do not operate the device near any sources of
electromagnetic interference.
Electrostatic Discharge (ESD) Precaution: Be sure to take the appropriate
Electrostatic Discharge (ESD) precautions. Disconnect the cables before
moving, cabling, or performing any set up procedures. Connectors marked
with the ESD protection symbol should not be touched. For detailed handling procedures,
see Section 3.6.
Turn off all system power and disconnect the power cord from the system and the wall
before attempting to clean the unit. The Trex HD unit can be wiped clean with a soft, damp
cloth using non-conductive distilled water, electrically non-conductive inert surfactants or a
Natus -approved cold sterilizing agent. It is important to dry off the unit quickly. Avoid letting
liquid seep into any of the internal electronics of the system. Do not use any abrasive
cleaner on the system.
When the Trex HD amplifier is in the Trex HD IPX2-certified pouch (p/n 105495), it is
offered protection from dripping water from above the device for up to 10 minutes in
duration.

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Natus systems are not AP or APG rated. DO NOT USE a Natus system in the presence of
a flammable anesthetic mixture with air, oxygen, or nitrous oxide.
Device accessories may include several kinds of disposable, sterile needle electrodes.
These needles are labeled as STERILE and the method of sterilization is documented on
the packaging. These electrodes should not be used if the sterile packaging has been
tampered with.
The two AA batteries used to operate the Trex HD should be removed when the Trex HD is
not in use.
Dispose of used, non-rechargeable batteries in accordance with local regulations, and
manufacturer’s instructions.
The Trex HD needs special precautions regarding Electromagnetic Compatibility (EMC) and
must be installed and operated according to EMC guidelines (see Section 2.1.2).
Using the Trex HD with cables and accessories not approved by Natus may negatively
affect EMC performance, including electromagnetic immunity (see Section 2.1.3).
External equipment may interfere with the performance of the Trex HD, even if that other
equipment complies with CISPR Emission requirements (see Section 2.1.3).
The Trex HD should not be used adjacent to or stacked with other equipment. If adjacent or
stacked use is necessary, the amplifier should be observed to verify normal operation in the
configuration in which it will be used. See Section 2.1.2 for minimum recommended
separation distances.
Do not connect items which are not specified as part of the Trex HD system to the system.
Never use equipment that has parts missing or equipment that might contain loose parts
inside of it (that is, inside an enclosed portion of the equipment). If you suspect a piece of
equipment has missing or loose parts, contact Natus. Routinely inspect system cables and
components for regular wear and tear.
WARNING: Third-party software installed on the acquisition computer may interfere with the
operation of the Natus software. Please consult Technical Support before installing third-
party software on the computer.
WARNING: No modification of this equipment is allowed.
Do not install the Trex HD system or use an electrical outlet within 10 feet of a swimming
pool.

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Do not use with an electrical outlet in the bathroom.
3.2. Electrical Warnings and Cautions
Natus systems are intended for connection to a properly grounded electrical outlet only.
Conductive parts of electrodes and their connectors are not to contact other conductive
parts including earth.
Do not place MULTIPLE PORTABLE SOCKET-OUTLETS (MPSOs) on the floor.
Do not connect additional MPSO’s or extension cords to the Trex HD system.
Do not use the MPSO with the Trex HD system for supplying power to any equipment that is
not part of the system.
To avoid the possible hazards caused by the summation of leakage currents when all the
parts of the system are interconnected, no equipment other than devices connected to the
Trex HD may be powered by the isolation transformer.
The current rating of the isolation transformer must be sufficient to operate all of the devices
powered by it. Refer to the current ratings of the isolation transformer and current rating for
each individual device connected.
Do NOT connect non-medical equipment which has been supplied as part of the system
directly to the wall outlet when the system is supplied, via MPSO, with a separating
transformer.
Do NOT connect electrical equipment which has not been supplied as a part of the system
to the MPSO.
ELECTRICAL SHOCK HAZARD: Do NOT turn on the system power until all cables have
been connected, verified and visually inspected for any damage. Failure to inspect the
cables may result in electrocution. Verification of electrical safety should be performed
routinely.
ELECTRICAL SHOCK HAZARD: Do NOT service the system. Refer servicing to qualified
personnel only. Do NOT use repaired components without proper testing.

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3.3. Electrostatic Discharge (ESD) Precautions:
Electrostatic Discharge (ESD) Precaution: Be sure to take the appropriate
Electrostatic Discharge (ESD) precautions. Disconnect the cables before
moving, cabling, or performing any set up procedures. Connectors marked with
the ESD protection symbol should not be touched. For detailed handling
procedures, refer to the Electrostatic Discharge Handling Procedure section.
3.4. Wireless Option Warnings and Cautions
Like other wireless devices, this feature is limited in operating range. The range will also be
reduced substantially if there is any physical interference between the acquisition computer
and the Trex HD. In either of these situations, the wireless data will not be received by the
acquisition computer.
The Trex HD contains FCC ID: R47F2M03GL which complies with part 15 of the FCC
Rules. Operation is subject to the following two conditions:
(1) This device may not cause harmful interference, and
(2) This device must accept any interference received, including interference that may
cause undesired operation.
Changes or modifications not expressly approved by the party responsible for compliance
could void the user’s authority to operate the equipment.
The Trex HD contains F2M03GLA which has passed the Bluetooth
Qualification/Certification process as specified within the Bluetooth Specifications and as
required within the PRD 2.0.
QDID: B012541.
Mobile RF communications equipment may affect the Trex HD and interfere with wireless
operation. See Section 2.1.3 for guidelines.
3.5. Patient Environment Warnings and Cautions
NOTE: The patient environment is defined as the area within 1.5 meters of the patient
laterally and within 2.5 meters of the floor in the area occupied by the patient.
The Trex HD amplifier is NOT intended for use with High Frequency Surgical Equipment.
Connect all patient electrodes to fully electrically isolated physiological devices only.
Connecting patient electrodes to any other device or external outlet may result in personal
injury.
The amplifier accepts only touchproof style electrode inputs. Do NOT attempt to use any
other style of patient electrode input.

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The patient event button attached to the Trex HD is NOT intended for critical patient-safety-
related incidents.
Patient connections are NOT intended for direct cardiac contact.
As with all medical equipment, carefully route patient cabling to reduce the possibility of
patient entanglement or strangulation.
Connecting other medical equipment, such as an electrical stimulator, simultaneously to the
same patient may constitute a safety hazard.
Do NOT touch any Trex HD system accessible metal parts and the patient simultaneously.
Do not use the Trex HD system in the vicinity of MRI or CT systems.
Do not allow loose electrodes to contact metal parts.
As with all medical equipment, carefully route patient cabling to reduce the possibility of
patient entanglement or strangulation.
User is not to position ME equipment in such a way as to make it difficult to operate the
disconnection device.
Potential allergic reactions could occur with the use of system accessories and application
products. Consult clinician on any allergies before use.
Do not use the Trex HD system when outside the Trex HD pourch as the device is not IPX
certified when used outside of the pouch.
3.6. Pulse Oximeter Warnings
The Nonin XPOD pulse oximeter is to be operated by qualified personnel only. This manual,
the instructions for use for any pulse oximeter sensor or cable extender, the accessory
directions for use, all precautionary information, and specifications should be read prior to
use.
EXPLOSION HAZARD: Do not use the pulse oximeter in the presence of flammable
anesthetics or other flammable substance in combination with air, oxygen-enriched
environments, or nitrous oxide.

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A pulse oximeter should NOT be used as an apnea monitor.
A pulse oximeter should be considered an early warning device. As a trend towards patient
deoxygenation is indicated, blood samples should be analyzed by a laboratory co-oximeter
to completely understand the patient’s condition.
Significant levels of dysfunctional hemoglobins (HbCO or MetHb) may cause inaccurate
measurements.
Intravascular dyes such as indocyanine green or methylene blue may cause inaccurate
measurements.
Excessive illumination may cause inaccurate measurements or loss of pulse signal.
Excessive patient movement may cause inaccurate measurements.
Venous pulsations may cause inaccurate measurements.
Carboxyhemoglobin may erroneously increase readings. The level of increase is
approximately equal to the amount of carboxyhemoglobin present. Dyes, or any substance
containing dyes, that change usual arterial pigmentation may cause erroneous readings.
Loss of pulse signal can occur when the patient has hypotension, severe vasoconstriction,
severe anemia or hypothermia.
Loss of pulse signal can occur when there is arterial occlusion proximal to the sensor.
Loss of pulse signal can occur when the patient is in cardiac arrest or is in shock.
Do not immerse the sensor in water, solvents, or cleaning solutions. Do not sterilize the
sensor by irradiation, steam or ethylene oxide.
Do not immerse patient cables in water, solvents, or cleaning solutions (the patient cable
connectors are not waterproof). Do not sterilize patient cables by irradiation, steam or
ethylene oxide.
As with all medical equipment, carefully route cables and connections to minimize the
possibility of entanglement or strangulation.

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Operation of this module below the minimum amplitude of 0.3% modulation may cause
inaccurate results.
Oximeter readings may be affected by the use of an electrosurgical unit (ESU).
Inspection of monitors, cables, and probes should be completed prior to each use to ensure
compatibility and maintain patient safety.
The Trex HD amplifier system does NOT include SpO2or Pulse Rate alarms.
3.7. Pulse Oximeter Sensor Warnings
Before using, carefully read the sensor directions for use.
Use only Nonin oximetry sensors, as required, for SpO2 measurements. These sensors are
manufactured to meet the accuracy specifications for the pulse oximeter. Other oxygen
transducers (sensors) may cause improper pulse oximeter performance.
Tissue damage can be caused by incorrect application or use of a pulse oximetry sensor
(i.e. by wrapping the sensor too tightly). Inspect the sensor site as directed in the sensor
directions for use to ensure skin integrity and correct positioning and adhesion of the
sensor.
Patient sensitivity may vary due to medical status or skin condition. Discontinue use of
adhesive tape strips if the patient exhibits an allergic reaction to the adhesive material.
Do not use pulse oximetry sensors during MRI scanning as this could potentially cause
burns. The pulse oximeter may affect the MRI image, and the MRI unit may affect the
accuracy of the oximetry measurements.
Placement of a sensor on an extremity with a blood pressure cuff, arterial catheter, or
intravascular line may cause inaccurate measurements.
Loss of pulse signal can occur when the sensor is too tight.
Do not use damaged pulse oximetry sensors. Do not use sensors with exposed optical
components. Do not immerse the sensor in water, solvents or cleaning solutions (the
sensors and connectors are not waterproof). Do not sterilize by irradiation, steam, or
ethylene oxide. See the cleaning instructions in the directions for use for the reusable pulse
oximetry sensors.