Dive Rite NiTek He User Guide

NiTekHeDiveComputer

NiTekHeDiveComputer

UserGuide

Dateofpurchase:

www.diverite.com

Content

DEVELOPED
BY

COPYRIGHT
NOTICE

WARRANTY
INFORMATION

Dive Rite
175 NW Washington Street
Lake City, FL 32055
Phone: [phone]
Fax: [phone]
Web: www.DiveRite.com

Copyright © 2003 Lamartek, Inc. dba Dive Rite
This manual is copyrighted by Lamartek, Inc. dba Dive Rite.

You may not reproduce, translate, transcribe, or transmit any
part of this manual without express, written permission from
Lamartek, Inc. dba Dive Rite.

Dive Rite will—at its sole discretion—repair or replace NiTek
He components proved to be damaged by faulty manufacture
or material, at no cost, for a period of up to one year (365
days) from the date of purchase.

This warranty applies only to the original retail purchaser. It
does not cover commercial or rental use, nor does it extend to
units purchased from other than an authorized Dive Rite
dealer.

This warranty specifically excludes battery depletion or other
conditions resulting from misuse, negligence, alteration,
accident, or unauthorized repair.

To make a claim under this warranty, the owner must have
registered his/her warranty using Dive Rite’s website
(www.diverite.com). He or she must then return the damaged
items to Dive Rite, along with a copy of the original purchase
invoice or receipt. No warranty service will be performed for
other than registered owners.

This warranty becomes void if NiTek He components are
damaged by anything other than normal recreational diving
use, or if they have been serviced or repaired by other than
authorized Dive Rite dealers.

Repairs made under this warranty will not extend the warranty
period.

All further claims, especially for damage after diving accidents,
are excluded from coverage under this warranty.

Dive Rite has no obligation to honor any extension of this
warranty.

This warranty is in lieu of all other warranties, express or
implied. No other person or representative is authorized to
assume for Dive Rite any other liability in connection with the
sale of this product.

NiTek He Dive Computer User Manual i

Content

Table of contents

Chapter 1 Introduction • 1

Overview • 2
Features and functions • 3
Specifications • 5
Warnings • 6

Chapter 2 Using the NiTek He • 9

Getting started • 10
Accessing display modes and screens • 11
Surface mode • 12
Time display and set mode • 13
Dive option set and display mode • 15
Plan mode • 24
Computer mode • 26
Gauge mode • 35
Log mode • 36
Profile mode • 39
PC transfer mode • 41
Surface mode (upon surfacing from a dive) • 43
Altitude operation • 45

Chapter 3 Care and maintenance • 47

Proper handling techniques • 48
Low battery warning • 50

Index 51

ii NiTek He Dive Computer User Manual

Chapter 1

Introduction

Summary

This chapter provides an overview of the NiTek He, lists the
NiTek He’s features and functions, and covers warning
information that should be read before using your NiTek He.

Content

Overview • 2
Features and functions • 3
Specifications • 5
Warnings • 6

When diving… • 7

NiTek He Dive Computer User Manual 1

Introduction

Overview

Congratulations on your purchase of the NiTek He dive
computer. The NiTek He is a sophisticated and comprehensive
dive computer that was designed to offer you the latest in dive
computer technology, safety, and reliability.

The NiTek He dive computer is a multifunctional computer for
recreational diving, providing information on depth, dive times,
no-decompression and decompression times, and nitrogen and
helium absorption and elimination during all dive phases,
including ascent, surface interval times, and subsequent dives.

This information is displayed on an easy-to-read display,
providing simple and direct communication between the diver
and the computer. With an easy-to-read display, the diver has no
problem following and reading the displayed information.

The NiTek He comes standard with a number of modes,
including a time mode, dive set mode, dive plan mode, log
mode, profile mode, PC transfer mode, and dive mode.

Note: It is extremely important that you carefully read and

understand this manual. Make sure you fully understand how the
NiTek He operates before diving with it.

This manual has been divided into three chapters:

• Introduction: Covers the features and functions,

specifications, and warnings for the NiTek He

• Using the NiTek He: Covers the operation of each mode for

the NiTek He

• Care and maintenance: Covers how to properly care for

and maintain the NiTek He and change the battery

2 NiTek He Dive Computer User Manual

Introduction

19,685

Features and functions

The NiTek He incorporates a number of important modes and
features:

• The NiTek He turns on automatically upon descent

• On the surface, the NiTek He constantly displays a minimum
of date and time

• The NiTek He uses easily accessible and highly reliable push
buttons instead of exposed electrical contacts

• The NiTek He can be programmed to monitor exposure to
seven different gas mixtures during a dive. Gas mixtures
including combinations of oxygen, helium, and nitrogen can
be programmed. Underwater, NiTek He users can switch
between mixes at the push of a button.

• The NiTek He is capable of functioning up to a depth of 394
feet (120 meters) when in dive computer mode and 656 feet
(200 meters) when in gauge mode

• The NiTek He automatically adjusts for altitudes up to
19,680 feet (6,000 meters)

• The NiTek He displays a variety of data underwater
including: date, time of day, current and maximum depths,
no-decompression dive time elapsed and remaining, and
water temperature

• The NiTek He displays data specifically related to the use of
Enriched Air Nitrox (EANx) including: fraction of oxygen
(FO2) setting, partial pressure of oxygen (PO2), and an
oxygen limit index (OLI) representing the cumulative effect
of a diver’s exposure to elevated PO2s (the theoretical “CNS
clock”) as a bar graph

• Through a combination of audible and visible alarms, the
NiTek He helps to alert the diver to a number of possibly
hazardous situations including: violation of ascent rate, no­decompression state, and whether mandatory decompression
stops are necessary or if the diver has ascended above a
mandatory stop ceiling. Nitrox specific warnings occur when
the diver approaches or exceeds a limiting PO2 of 1.4 or 1.6

NiTek He Dive Computer User Manual 3

Introduction

atmospheres depending on what is set, and when cumulative
exposure to elevated PO2s exceeds recommended limits.

• The NiTek He can be programmed to display data in
Imperial or metric units

• Dive depth can be displayed in fresh or salt water
equivalents

• Special mode indicators makes it easy to determine what
display mode or screen you are in at any time

• The NiTek He has a back light to illuminate the screen,
while in dive mode

• The NiTek He’s memory capability enables it to hold and
display log data on up to 30 hours of dive time or 60 dives

• Detailed dive-profile information can be stored for each dive
through user-programmable sample intervals of 15 or 30
seconds (longer intervals allow data for a greater number of
dives)

• Dive data can be uploaded and stored in a dive log format on
a desktop or laptop computer using the NiTekLogic™
software and optional PC interface

4 NiTek He Dive Computer User Manual

Introduction

8 oz.

699

during dive mode

19685

Specifications

Algorithm: Buhlmann ZH-L16
Sample tissues: 16
Tissue half-lives: from 5 to 640 minutes
Size and weight

Length: 4.25 in (10.8 cm)
Height: 1.25 in (3.2 cm)
Weight: ounces ( g)

Display face

Backlight illumination
Low battery indicator
Two user buttons
Water immersion switch

Depth sensor

Sea and fresh water calibration
Measuring range: 0 to 394 feet (0 to 120 m) measured every second
(Gauge mode 656 feet (200 m)
Accuracy: +/- 3% + 2 feet (0.5 m)
Surface interval time: from 0 to 48 hrs
Diving time: from 0 to 599 minutes
Ascent rate warning: 26 to 59 feet per minute (8 to 18 m)

Thermometer

Measuring range: 23 °F to 104 °F (-5 to 40 °C)
Accuracy: +/- 4 °F (2 °C)
Measurement interval: Every minute

Clock

Accuracy: +/- 30 sec on average per month
24-hour display

Altitude

Altitude function monitoring: from 0 to 19,680 feet (6,000 m) measured
every 10 minutes
Measurement interval: Every 10 minutes

Battery

Li/MnO2 CR 2032 3V button battery
Average battery life: About 3 years (50 dives/year)
Replacement: User replaceable

Breathing gas

Mixes: 7 gas settings
O2 setting range: 8 to 99 percent
O2 setting: 1% increments
He setting range: 0 to 92 percent
He setting: 1% increments

Dive log

Dive logging: Maximum of 60 dives
Profile logging: Maximum of 30 hours
Profile sampling rates: 15 or 30 seconds

NiTek He Dive Computer User Manual 5

Introduction

Warnings

This information has been developed for your safety. Please read
and understand this manual completely before using your NiTek
He dive computer.

Important safety information:

• Before using your NiTek He, it is extremely important that
you read the following points—as well as similar warning
and caution notices that appear throughout this manual.
Failure to do so could result in damage to or loss of
equipment, serious personal injury, or death.

• The NiTek He is designed for use by certified divers who
have maintained a sufficient level of knowledge and skill
proficiency through a combination of formal training,
ongoing study, and experience. It is not intended for use by
persons who lack these qualifications and thus, may not be
able to identify, assess, and manage the risks scuba diving
entails. Use of the NiTek He in conjunction with Enriched
Air Nitrox (EANx) or Trimix requires that divers be trained
and certified for Nitrox diving.

• The NiTek He is not intended for use by commercial or
military divers whose activities may take them beyond the
commonly accepted depth limits for recreational or technical
diving.

• Although the NiTek He is capable of calculating
decompression stop requirements, users must remember that
dives requiring mandatory stage decompression carry
substantially greater risk than dives made well within no­decompression limits.

• The NiTek He is designed for use by one diver at a time.
Divers should not share a single NiTek He—or any other
dive computer—on the same dive. Additionally, no diver
should lend their NiTek He to anyone else until it calculates
that no measurable residual nitrogen remains after previous
dives and no longer displays the “desaturation time”
indicator while in time mode. Further, no diver should use
their NiTek He for repetitive dives—unless that same
properly functioning NiTek He has accompanied them on all

6 NiTek He Dive Computer User Manual

Introduction

Do we want to 
suggest that 
someone buy 
a second 
computer to 
backup the 
information on 
the Nitek HE?

previous dives in the same repetitive dive series and is thus,
accurately monitoring the diver’s total exposure to oxygen,
helium, and nitrogen.

• Neither the NiTek He—nor any other dive computer—
physically measures the amount of nitrogen present in body
tissues or the rate at which nitrogen is being absorbed or
released. The NiTek He monitors depth and time, and uses
this data to work a mathematical formula designed to
emulate how individuals in good general health and whose
physical characteristics do not place them among those at
higher risk of decompression illness (DCI) are assumed to
absorb and release nitrogen from body tissues. Thus, the
NiTek He cannot compensate for factors such as age,
obesity, dehydration, cold, or exertion, which experts believe
place divers at greater risk of DCI. If these, or similar factors
apply to you, use the NiTek He—and other dive computers
or dive tables—with even greater caution.

• Experts still know surprisingly little regarding the exact
nature and causes of decompression illness (also known as
decompression sickness, DCI, or DCS). Susceptibility to
DCI may vary substantially from person to person and from
day to day. Neither the NiTek He—nor any other dive table
or computer—can guarantee that you will not suffer
decompression illness. Even though you use these items
correctly, you may still suffer DCI. Use your NiTek He
conservatively and in conjunction with other dive planning
devices, such as dive tables. Do not rely on the NiTek He, or
any similar device, as your sole means of avoiding
decompression illness.

When diving…

• Do not “push” the no-decompression limits (NDLs). Make
safety stops before ascending. If you exceed the no­decompression limits, check your breathing gas supply at all
stop depths.

• The NiTek He does not monitor breathing gas supply. You
must monitor this yourself, on every dive, using a
submersible pressure gauge or equivalent device.

NiTek He Dive Computer User Manual 7

Introduction

• Do not rely solely on this or any other dive computer. Take a
back-up dive computer or dive tables (along with a separate
means of monitoring depth and dive time).

• Be aware that the NiTek He makes assumptions regarding
residual nitrogen based on altitude settings. Avoid making
abrupt changes in altitude following a dive, as doing so may
be very dangerous.

8 NiTek He Dive Computer User Manual

Chapter 2

Using the NiTek He

Summary

This chapter provides topics about using, setting, and
understanding each of the modes and options of the NiTek He.

Content

Getting started • 10
Accessing display modes and screens • 11

Button operation • 11

Surface mode • 12

Entering surface mode from another
mode • 13

Time display and set mode • 13

Setting the time and date • 13

Dive option set and display mode • 15

Using computer mode • 15
Setting Mix1 through Mix7 gas
percentages • 17
Setting the maximum depth alarm • 18
Setting the dive time alarm • 18
Setting the dive profile sampling rate • 19
Setting for fresh or salt water use • 20
Setting the computer for metric or Imperial
operation • 21
Understanding default mode • 21

Using gauge mode • 22
Plan mode • 24
Computer mode • 26

Primary underwater screen • 26

Second underwater screen • 27

Changing gas mixes underwater • 28

Warnings while in diving mode • 29
Gauge mode • 35
Log mode • 36
Profile mode • 39
PC transfer mode • 41

Before transferring the dive log • 41
Surface mode (upon surfacing from a dive) • 43
Altitude operation • 45

NiTek He Dive Computer User Manual 9

Using the NiTek He

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puncuaton for 
consistentcy

Getting started

The NiTek He has many modes and screens and a number of
options that can be changed depending on your dive location and
profile. The following is a checklist of general things that you
should pay attention to before, during, and after a dive.

Before a dive

• Check that the proper time and date are set. If you traveled,
your NiTek He may be set to your home time zone.

• Check that the proper mixes are set. If you are using gauge
mode, make sure it is set to “GAGE.”

• Make sure that you review the dive plan mode for maximum
depths and times for the mixes you are using

During a dive

• Monitor the NiTek He throughout your dive for depth and
time

• Monitor the PGT and O2 loading bar graphs

• Pay attention to any alarms, such as an ascent rate warning

• Follow the no-decompression limits or complete the required
decompression displayed

After a dive

• Monitor surface interval time if making another dive

• Follow the no-fly requirements

• Review your dive using the log mode and profile mode

• Download the dive log to your PC if you have the optional
PC interface

10 NiTek He Dive Computer User Manual

Using the NiTek He

A (mode)

button

B

button

Accessing display modes and screens

There are some display modes that the NiTek He enters and/or
exits automatically. For example, by taking the NiTek He
underwater, the dive mode automatically turns on. Upon
surfacing, the NiTek He automatically enters the surface mode.

To access other modes or screens, requires the use of the NiTek
He’s buttons.

Button operation

The NiTek He has two buttons (A (mode) and B), which are
used to access the different modes and screens. To use the
buttons, simply press the button once or hold the button down
depending on what you are trying to do. The correct procedure to
use is clearly defined in each topic throughout the manual.

• A (mode) button: This button is used to select and scroll
through the different modes, such as time mode and locks in
setting values when setting options

• B button: This button is used to set an option’s setting, such
as setting the date

The front of the NiTek He, showing the two buttons that are used
to access and setup the different modes and options

NiTek He Dive Computer User Manual 11

Using the NiTek He

2

Surface mode

Surface mode is the NiTek He’s default mode, with “SURF”
displayed on the screen. The computer returns to this mode
automatically upon surfacing from a dive and from other modes
when two to three minutes of inactivity have passed.

The NiTek He may display additional information concerning
exposure to nitrogen and oxygen, desaturation time, surface
interval time, and altitude. These items are covered in “Surface
mode (upon surfacing from a dive)” and “Altitude operation.”

1

(1) Date: This is the month and day. The first digit is the month
and the second digit is the day. For example, 1-24 represents the
twenty-fourth day of January.

(2) Time of day: This is the time of day expressed in hours and
minutes. Time can be displayed in 24-hour (military) format or
12-hour format. When in 12-hour format, an AM or PM appears
on the screen.

Entering surface mode from another mode

When you are using other modes, it is very easy to return to
surface mode. Simply, press and hold button A for two to three
seconds or press button A until “SURF” is displayed.

12 NiTek He Dive Computer User Manual

Using the NiTek He

4

3

Time display and set mode

Time display and set mode is used to set and view the time of
day and date. When you enter this mode, “TIME” is displayed
on the screen.

1

2

(1) Date: This is the month and day. The first digit is the month
and the second digit is the day. For example, 1-24 represents the
twenty-fourth day of January.

(2) Year: This is the year.
(3) Time of day: This is the time of day expressed in hours and

minutes. Time can be displayed in 24-hour (military) format or
12-hour format. When in 12-hour format, an AM or PM appears
on the screen.

(4) Seconds: This is the seconds for the time of day.

To display the time and date:

1. Press and hold button B while in surface mode.

2. Release button B to return to surface mode.

Setting the time and date

Setting the time and date are done in the time set mode. You can
enter or change the year, month, day, hours, minutes, and
seconds in this mode.

NiTek He Dive Computer User Manual 13

Using the NiTek He

To set the time and date:

1. Press and hold button B for four to five seconds while in
surface mode.

The “seconds” field flashes.

2. Press button B to “00” the seconds field or press button A to
select another field, such as the minutes field.

3. Using buttons A and B, set the year, month, day, hour,
minutes, seconds, and whether you want the time displayed
in 24-hour format.

For example, 1:00 PM would be 13:00.

4. When finished, press button A for two to three seconds to
return to surface mode.

14 NiTek He Dive Computer User Manual

Using the NiTek He

123

4

8

9

Dive option set and display mode

Dive option set and display mode is where all “dive” option
settings are displayed and set up.

Using computer mode

Computer mode is when the NiTek He is operating in the normal
computer mode. “DIVE” is displayed on the screen and all
computer mode functions operate normally. The dive option set
and display mode is used to review and change option settings
that pertain to an upcoming dive. The operating depth limit when
in dive operation is 394 feet (120 meters).

When the computer is in dive set mode, “SET” is displayed on
the screen. There are three screens that are used to set up all of
the computer mode options.

5

Dive option display and set fields for screen one

6

7

Dive option display and set fields for screen two
NiTek He Dive Computer User Manual 15

Using the NiTek He

10

11

Dive option display and set fields for screen three

(1) Mix number: This is the mix number you are setting.
(2) PO2 alarm setting: This is the PO2 alarm setting for the mix

number selected. The PO2 alarm can be set for either 1.4 or 1.6.
(3) FO2 gas percentage: This is the oxygen percentage for the

mix number selected. The O2 percentage setting range is 8 to 99
percent.

(4) FHe gas percentage: This is the helium percentage for the
mix number selected. The He percentage setting range is 0 to 92
percent.

(5) Maximum operating depth (MOD) for FO2 setting: This
is the safe operating depth (maximum) for the mix selected. This
is based on a limiting PO2 factor of either 1.4 or 1.6
atmospheres.

(6 and 7) Max depth alarm: This is an alarm that can be set to
sound when a maximum depth is reached. When the alarm is
turned on, the maximum depth alarm symbol is displayed.

(8 and 9) Maximum time alarm: This is an alarm that can be
set to sound when a maximum dive time is reached. When the
alarm is turned on, the “clock” alarm symbol is displayed.

(10) Dive log profile sampling rate: This is how frequently
depth data is measured stored during a dive, which is 15 or 30
seconds.

(11) Salt or fresh water: This is the setting for salt water or
fresh water use.

16 NiTek He Dive Computer User Manual

Using the NiTek He

0-92%

To enter dive set mode:

1. Press button A until “SET” is displayed.

2. Press button B to enter the dive set up option screen.

3. Using the topics that follow, set up your desired dive option
settings.

Setting Mix1 through Mix7 gas percentages

You must set the breathing mix you plan on using on your dive.
There are up to seven different mixes that can be used for any
one dive. Not all of the mixes have to bet set, only the mixes that
you plan on using. Each mix can have an oxygen (FO2) and
helium (He) setting.

• FO2 percentages can be set for 8 to 99 percent oxygen

• FHe percentages can be set for 0 to 79 percent helium

Note: If you only plan on using one mix on your dive, you only

need to set mix1.

To set gas mix percentages:

1. Press button A until “SET” is displayed.

2. Press button B to enter the dive set up option screen.

Mix1 is flashing.

3. Press button B to change the mix number to the desired mix
number that you want to set or change.

4. Press button A to select the PO2 setting.

5. Press button B to set the PO2 setting for the selected mix
number.

6. Press button A to select the O2 gas percentage.

7. Press button B to set the O2 percentage you are setting for
the selected mix number.

Note: Maximum operating depth changes for the O2

percentage selected.

8. Press button A to select the He gas percentage.

NiTek He Dive Computer User Manual 17

Using the NiTek He

9. Press button B to set the He percentage you are setting for
the selected mix number.

10. When finished, press button A to advance to the next option
(maximum depth alarm) or to exit, press and hold button A
for two to three seconds to return to surface mode.

Setting the maximum depth alarm

The NiTek He has a maximum depth alarm that is activated
when the diver reaches the maximum depth that is set. When the
max depth is reached, an audible alarm sounds and the display
flashes for three seconds.

The alarm can be turned on or off and can be set from 30 to 390
feet (9 to 120 meters).

To set the maximum depth alarm:

1. Press button A until “SET” is displayed.

2. Press button B to enter the dive set up option screen.

Mix1 is flashing.

3. Press button A until the screen changes and maximum depth
is flashing.

4. Press button B to set the depth when you want the alarm to
sound.

5. Press button A.

The max depth alarm on/off flashes.

6. Press button B to toggle the alarm on or off.

7. When finished, press button A to advance to the next option
(dive time alarm) or to exit, press and hold button A for 1 to
2 seconds to return to surface mode.

Setting the dive time alarm

The NiTek He has a dive time alarm that is activated when the
diver reaches the dive time that is set for the dive. When the dive
time is reached, an audible alarm sounds and the screen flashes
for three seconds. Dive time alarm can be used when you want to

18 NiTek He Dive Computer User Manual

Using the NiTek He

(30 sec is default)

Stores 
depth, 
time, 
temperature
, gas 
changes, 
violations

set a maximum dive time for your dive. The alarm indicates
when this time has expired.

The alarm can be turned on or off and can be set from 10 to 690
minutes.

To set the dive time alarm:

1. Press button A until “SET” is displayed.

2. Press button B to enter the dive set up option screen.
Mix1 is flashing.

3. Press button A until the screen changes and maximum time
is flashing.

4. Press button B to set the time when you want the alarm to
sound.

5. Press button A.

The dive time alarm on/off flashes.

6. Press button B to toggle the alarm on or off.

7. When finished, press button A to advance to the next option
(dive profile sampling rate) or to exit, press and hold button
A for 1 to 2 seconds to return to surface mode.

Setting the dive profile sampling rate

The NiTek He allows you to choose how frequently it samples
and stores depth data. The data it samples and stores is used in
profile mode or when the data is uploaded to a personal
computer. There are two sampling rates to choose from, 15­second and 30-second.

The 15-second sampling rate enables the computer to sample and
store depth data every 15 seconds during a dive. The 15-second
sampling rate provides a more detailed dive profile, but because
it stores more information, fewer dives can be stored.

The 30-second sampling rate enables the computer to sample and
store depth data every 30 seconds during a dive. The 30-second
sampling rate is the computer’s “default” setting. The 30-second
rate provides a less detailed dive profile, but it is capable of
storing more information for more dives.

NiTek He Dive Computer User Manual 19

Using the NiTek He

Note: When the computer’s memory storage is full, it overwrites

the oldest dive profile data stored with the new information.

To set the dive profile sampling rate:

1. Press button A until “SET” is displayed.

2. Press button B to enter the dive set up option screen.
Mix1 is flashing.

3. Press button A until the screen changes and the dive profile
sampling rate is flashing.

4. Press button B to toggle between 15- and 30-seconds.

5. When finished, press button A to advance to the next option
(salt or fresh water use) or to exit, press and hold button A
for 1 to 2 seconds to return to surface mode.

Setting for fresh or salt water use

The NiTek He is capable of operating using fresh or salt water
calculations. This is based on:

• One atmosphere of saltwater is 33 feet (10 meters)

• One atmosphere of freshwater is 34 feet (10.3 meters)

Before going diving, set the computer to the type of water you
are diving in. This allows for the most accurate calculations with
respect to no-decompression limits, etc.

To set for fresh or salt water use:

1. Press button A until “SET” is displayed.

2. Press button B to enter the dive set up option screen.

Mix1 is flashing.

3. Press button A until the screen changes and sea or fresh is
flashing.

4. Press button B to toggle between fresh or sea water.

5. When finished, press and hold button A for 1 to 2 seconds to
return to surface mode.

20 NiTek He Dive Computer User Manual

Using the NiTek He

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Setting the computer for metric or Imperial
operation

The NiTek He can calculate and give you values in Imperial
units or metric units. When in Imperial, depth values are
expressed in feet and temperatures are expressed in Fahrenheit
(°F). When in metric, depth values are expressed in meters and
temperatures are expressed in Celsius (°C).

To set for metric or Imperial operation:

1. Press button A until “SET” is displayed.

2. Press button B to enter the dive set up option screen.
Mix1 is flashing.

3. Press and hold buttons A and B simultaneously for 10
seconds.

The computer beeps and changes to either feet (FT) or

meters (M).

Understanding default mode

Once the computer’s gas mixes are programmed, the settings are
stored in the computer until midnight unless the computer is
underwater. When the computer defaults, all gas mixture settings
change to 99 percent oxygen, 99 percent helium, and 99 percent
nitrogen. This is designed to help prevent the diver from diving
with the NiTek He when it is has not been properly programmed
to reflect the actual gases they are breathing.

If you try to dive the NiTek He when it is in default mode, an
alarm sounds signaling that you should return to the surface and
enter the correct gas percentages. If you ignore the warning and
go diving anyway, your bottom time is going to be severely
shortened and your decompression time severely lengthened.
The computer also shows that you have exceeded the allowable
oxygen exposure limit immediately.

The only exception to default mode occurs when the computer is
programmed with an air mixture (21% O2, 79% N2, 0% He).
When the computer is set to air, it will not default until the gas
mixtures are set to a percentage other than air.

NiTek He Dive Computer User Manual 21

Using the NiTek He

See note earlier

in gauge mode

The best way to deal with default mode is to simply avoid it. The
way to avoid it is, make sure that prior to every dive you check
the gas mixture settings. Make sure they accurately match what
you are going to breath during the dive.

Note: You should not rely on the NiTek He as the sole means of

tracking your exposure to elevated partial pressures of oxygen. It
is recommended that you use either a second computer or
another tracking method, such as dive tables.

Using gauge mode

If you do not want to use the NiTek He as a normal “dive
computer,” the NiTek He has a gauge operation. Gauge
operation is when the NiTek He is operating simply as a depth
gauge and bottom timer. “GAGE” is displayed on the screen.
Exposure to nitrogen and oxygen and no-decompression limits
are not tracked and no bar graphs are displayed. This mode is
used by divers who are relying solely on dive tables for
decompression information. The operating depth limit when in
gauge operation is 656 feet (200 meters).

Note: You cannot select gauge operation if the computer

calculates that there is still residual nitrogen remaining from a
previous dive. Also, you cannot return to dive computer
operation until 48 hours have passed since your last dive.

In gauge mode, you can still set the profile sampling rate, salt or
fresh water use, and the maximum depth and time alarms. For
more information on these options, see “Dive option set and
display mode.”

22 NiTek He Dive Computer User Manual

Using the NiTek He

To select and setup gauge operation:

1. Press button A until “SET” is displayed.

2. Press button B to enter the dive set up option screen.

Mix1 is flashing.

3. Press button B until “G” is displayed for a gas mixture.

“GAGE” is displayed and the screen changes.

NiTek He Dive Computer User Manual 23

Using the NiTek He

2

Plan mode

Plan mode enables you to determine how long you can stay at
various depths while remaining within the no-decompression
limits. The no-decompression time limits are based on the gas
mix that is set for mix1. If you are making a dive within 24 hours
of a previous dive, the no-decompression time limits are based
on the residual nitrogen remaining.

The two most important values that are displayed on the screen
in plan mode are the depth and no-decompression time limit.

1

(1) Depth: When you first enter plan mode, the initial depth
displayed is 30 feet (9 meters). You can advance the depth in 10
foot (3 meter) increments. Fourteen different dive plan depth
increments can be displayed to a maximum depth of 160 feet (48
meters).

(2) No-decompression limit (NDL): Depending on the depth
displayed and the current FO2 setting, the available no­decompression limit, up to a maximum of 200 minutes, is
displayed. If the computer is in default mode, a series of
horizontal lines appears.

If the NiTek He calculates that there is residual nitrogen present
from previous dives, the available no-decompression limits are
shorter. Depending on how much residual nitrogen is present, no
NDL time may be displayed for some deeper depths. If this takes
place, a series of horizontal lines are displayed. Similarly, for
combinations of depth and FO2 that would cause a diver to

24 NiTek He Dive Computer User Manual

Using the NiTek He

exceed a limiting PO2 of 1.6 atmospheres, a series of horizontal
lines appears in place of the no-decompression limit.

To enter plan mode:

1. Press button A until “PLAN” is displayed.

2. Press button B to enter the plan mode screen.

3. Press button B to advance the depth.

The no-decompression time limits change automatically

based on the depth.

4. When finished, press and hold button A for 1 to 2 seconds to
return to surface mode.

WARNING: Do not plan dives to depths deeper than those for

which the NiTek He is capable of displaying an available no­decompression limit. Doing so could cause you to exceed the no­decompression limits or a limiting PO2 of 1.4 or 1.6
atmospheres. This may increase your risk of decompression
illness or CNS oxygen toxicity and can lead to serious personal
injury or death.

NiTek He Dive Computer User Manual 25

Using the NiTek He

5

679

8

Dive Mode-computer??

Computer mode

Computer mode is automatically entered when the computer
enters the water. It begins performing its dive calculations once
you descend below 5 feet (1.5 meters).

Caution: Prior to diving, always check to ensure that the FO2

and FHe settings are correct and that the computer is not in
default mode.

While in diving mode, the computer calculates and displays
information about your dive and prompts you with safety stop
information and warnings if needed.

While underwater, there are two screens you can toggle between
and you can switch to different gas mixes when needed.

Primary underwater screen

When you enter the water, the primary screen shows your depth,
remaining no-decompression limit, dive time, max depth, PO2
for selected mix, mix number, O2 and He percentages for gas
selected, and the OLI and PGT bar graphs.

1

2
3

4

(1) Depth: This is the current depth.
(2) Maximum depth: This is the maximum depth that has been

reached during the dive.
(3) PO2: This is the partial pressure of O2 at your current depth.

It is based on the FO2 settings for the mix selected.

26 NiTek He Dive Computer User Manual

Using the NiTek He

1

2

(4) O2 (OLI) bar graph: This is the oxygen limit index (OLI)
that calculates the cumulative effect of your exposure to elevated
partial pressures of oxygen (PO2s). There are a maximum of
eight bars. When all bars are displayed, it means that you have
used 100 percent of your “CNS” clock. This graph increases
when you descend due to higher partial pressures and may
decrease when you ascend.

(5) Dive time: This is the time spent (in minutes) underwater,
measured from the time you descended below 5 feet (1.5 meters).

(6) Remaining no-decompression limit (NDL): This is the time
that is remaining (in minutes) before you reach the no­decompression limit. This NDL time limit increases when you
ascend and decreases when you descend.

(7) Mix number: This is the mix number the computer is
currently calculating dive data for.

(8) O2 and He percentages: This is the oxygen and helium
percentages programmed for the gas mix number that is selected.

(9) PGT bar graph: This is how much nitrogen and helium the
computer assumes your body has absorbed. There are a
maximum of nine bars. When all bars are displayed, it means
that you are at or have exceeded the no-decompression limits.

Second underwater screen

While underwater, you can change to the second diving mode
screen that displays additional information. When you switch
screens, time of day and temperature are displayed.

NiTek He Dive Computer User Manual 27

Using the NiTek He

(1) Time of day: This is the current time of day.
(2) Temperature: This is the lowest temperature that has been

reached during the dive.

To display the second diving mode screen:

1. Press and hold button B.
The back light turns on, and the second screen is displayed.

2. Release button B to return to the primary diving mode
screen.

Changing gas mixes underwater

Because the NiTek He has the ability to use seven different gas
mixes during a dive, you need the ability to switch between these
mixes while underwater. When you switch mixes, the PO2
adjusts to reflect the current mixture you are breathing.

Note: Only switch gas mixes when you have reached the safe

operating depth limit for the gas you are switching to.

To change gases underwater:

1. Press button A.

The back light turns on and the mix number flashes.

2. Press button B to select a mix number.

28 NiTek He Dive Computer User Manual

Using the NiTek He

The O2 and He percentages change to the programmed mix

and the PO2 indicator changes to reflect the PO2 for the
selected mix.

Note: Only the mix numbers that have been programmed

with a gas mixture are available.

3. Press button A to lock in the mixture and return to the
primary diving mode screen.

Note: You cannot lock in a mix if it causes you to exceed a

PO2 of 1.6 atmospheres.

Warnings while in dive mode

While in diving mode, there are several warnings that you should
be alert to.

• Default warning

• Ascent rate warning

• PO2 limit warning

• PGT limit warning

• Oxygen limit index (OLI) warning

• Decompression warning

• Decompression stop violation warning

• Out-of-range warning

Default warning

If the computer is in default mode at the beginning of a dive, an
audible alarm sounds for three seconds. If you ascend and set the
mix percentages, you can restart the dive. See “Understanding
default mode” for more information.

Ascent rate warning

The NiTek He assumes that you keep your ascent rate within the
following limits:

Depth range Ascent rate

0 to 19 feet (0 to 5.9 meters) 26 feet (8 meters) per minute
20 to 58 feet (6 to 17.9 meters) 39 feet (12 meters) per minute
59 feet (18 meters) or deeper 52 feet (16 meters) per minute

NiTek He Dive Computer User Manual 29

Using the NiTek He

If you exceed these ascent rates, an audible alarm sounds for
three seconds and “slow” is displayed and flashes on the screen.
The warning displays until you slow your ascent to an acceptable
rate or you reach 5 feet (1.5 meters). If the ascent rate is violated
twice, the “slow” symbol appears in log mode after the dive.

PO2 limit warning

The PO2 warning indicates that you have exceeded the 1.4
atmospheres and/or 1.6 atmospheres for the gas you are
breathing. If you set the PO2 for 1.4 atmospheres, an alarm
sounds and the current depth and PO2 information flashes. If you
set the PO2 for 1.6 atmospheres, the OLI bar graph flashes in
addition to the alarm and current depth and PO2 flashing.

30 NiTek He Dive Computer User Manual

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PGT limit warning

The PGT limit warning indicates that you are approaching the
no-decompression limits. When seven or more bars are
displayed, an audible alarm sounds and the PGT graph flashes.

Oxygen limit index (OLI) warning

The NiTek He’s oxygen limit index (OLI) reflects the cumulative
effect of your exposure to elevated partial pressures of oxygen.
The PO2 warning only accounts for the intensity of the exposure,
but the OLI accounts for both the intensity and length.

When seven of the O2’s eight bars are displayed, the computer’s
audible alarm sounds for three seconds, and “OLI” flashes for
ten seconds. If you do not ascend to a shallower depth, and all
eight of the O2’s bars are displayed, the alarm sounds again and
“OLI” flashes. “OLI” continues to flash until the O2 bar graph
drops to seven bars. This warning appears in log mode after the
dive.

NiTek He Dive Computer User Manual 31

Using the NiTek He

2

345

Decompression warning

If you exceed the no-decompression limits, the computer enters
decompression mode. An audible alarm sounds for three seconds
indicating that you have decompression stop requirements.

Caution: Decompression diving is considered to substantially

increase your risk of decompression illness more than dives
made within no-decompression limits.

1

Decompression warning with “DECO” displayed on the screen

(1) Deco stop symbol: The “DECO” symbol displays indicating
that you have to stop at the depth displayed.

(2) Required stop depth: This is the required decompression
stop depth.

(3) Required stop time: This is the time you must remain at the
indicated stop depth.

(4) Total ascent time: This is the total amount of time (in
minutes) you must spend at the decompression stops and the
ascent time between decompression stops.

(5) PGT bar graph: This is how much nitrogen and helium the
computer assumes your body has absorbed. There are a
maximum of nine bars. When all bars are displayed, it means
that you are at or have exceeded the no-decompression limits and
have entered decompression.

32 NiTek He Dive Computer User Manual

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699

Decompression stop violation warning

A decompression stop violation warning takes place when you
ascend to a shallower depth than the indicated stop depth or if
you do not spend sufficient time at the required depth before
ascending. When you enter this violation, the computer’s audible
alarm sounds, and the current depth, stop depth, stop time, and
“DECO” flashes. These items continue blinking as long as you
remain shallower than the indicated stop depth.

Note: During a deco stop violation, the computer’s ascent rate

warning does not function.

Caution: If you do not correct an indicated deco stop violation,

the warnings continue for several minutes after surfacing. At this
point, the computer is not usable for the next 48 hours.

Out-of-range warning

The following can cause the out-of-range warning:

• Descend below the computer’s maximum operating depths
for computer mode or gauge mode

• Exceed an actual bottom time of 599 minutes

• Accrue a total ascent time of over 999 minutes

The out-of-range warning consists of:

• The audible alarm sounds for three seconds

• The entire screen flashes

NiTek He Dive Computer User Manual 33

Using the NiTek He

WARNING: A NiTek He displaying an out-of-range warning is

incapable of displaying other critical information such as depth,
time, ascent rate, PO2, OLI and deco stop violations, and
required decompression stops. For this reason, you should not,
under any circumstance, use a NiTek He in such a way that
would cause an out-of-range warning. Under such conditions, the
risk of serious personal injury or death would be substantial.

34 NiTek He Dive Computer User Manual

Using the NiTek He

Gauge mode

When selected, gauge mode is automatically entered when the
computer enters the water. It begins displaying depth and time
once you descend below 5 feet (1.5 meters).

Note: To enter and set up gauge mode operation, see “Using

gauge mode.”
While in gauge mode underwater, there are two screens you can

toggle between. The primary screen displays depth, time, and
maximum depth. The second screen displays time of day and
temperature.

To toggle between screens underwater:

1. Press and hold button B to switch to the second screen.

2. Release button B to return to the primary screen.

NiTek He Dive Computer User Manual 35

Using the NiTek He

8

5

679

10

12

Nothing stated about log starting once computer is 
below 5ft for 5 minutes or that re-decending within 
10 minutes resumes previous dive.

Log mode

For each dive, the NiTek He stores information, such as depth,
time, temperature, etc. in a log. This stored log information can be
viewed directly from the NiTek He’s screen when in log mode. A
to total of 30 hours or 60 dives can be stored.

Because of the amount of information the NiTek He stores, there
are two pages that you can toggle between for each dive. Each
dive is assigned a number and has a date for the day. Each log
page displays the log number and the page number, making it
easy for you to toggle between the dive log pages.

3

4
2

1

Page one for a dive in log mode

11

13

Page two for a dive in log mode

36 NiTek He Dive Computer User Manual

Using the NiTek He

(1) Log entry number: This is the sequence in which the log
appears. The most recent log entry has the highest number,
which began with log one. When the computer’s memory is full,
the oldest dives are overwritten with the new dives. This causes
the log entry number assigned to a particular dive to change.

(2) Page number: This is the log page number. Each dive has
two pages of logged information.

(3) Date: This the month and day of the dive.
(4) Descent time: This is the time you started the dive, indicated

by a down arrow.
(5) Ascent time: This is the time you surfaced from the dive,

indicated by an up arrow.
(6) PGT exposure bar graph: This is the amount of residual

nitrogen and helium in your body at the end of the dive.
(7) O2 OLI bar graph: This indicates CNS toxicity level at the

end of the dive.

(8) Dive time: This is the actual bottom time for the dive.
(9) FO2 and FHe gas percentages: These are the FO2 and FHe

gas percentages that you entered for the dive. All calculations
where based on these percentages.

(10) Mix number: This is the mix number used on the dive.
(11) Average depth: This is the average depth reached during

the dive.
(12) Temperature: This is the coldest temperature reached

during the dive. If the coldest temperature reached during the
dive is outside the range, “Hi” or “Lo” is displayed.

(13) Max depth: This is the maximum depth reached during the
dive.

To view a dive log:

1. Press button A until “LOG” is displayed.

2. Press button B to enter the log mode screen.

3. Press button B to change to the second page number for a
dive.

NiTek He Dive Computer User Manual 37

Using the NiTek He

-OR­ Press button B to scroll “down” through the logged dives. To

fast scroll, press and hold button B.

-OR­ Press button A to view all mixes used on the dive.

4. When finished, press and hold button A for 1 to 2 seconds to
return to surface mode.

38 NiTek He Dive Computer User Manual

Using the NiTek He

2

Profile mode

Profile mode enables you to see a record of the depths you
reached at various points during a dive. You can display a
detailed profile of each dive stored in the log. When a dive is
selected, the computer automatically displays the depth and the
time in the dive when you reached that depth until it reaches the
end of the dive.

Dive profile information is either stored in 15- or 30-second
intervals during a dive. This must be set in dive mode before a
dive. Refer to “Setting the dive profile sampling rate” for more
information.

The dive number and date of the dive are displayed when you
scroll through the dives. This makes it easy to find the dive
profile you want to view.

4

3

1

(1) Dive log number: This is the dive number that corresponds
to the dive number when in log mode.

(2) Dive time: This tells you at what time during the dive you
reached the depth indicated.

(3) Depth: This is the depth that corresponds to the displayed
dive time. Depending on what profile sampling rate you have set,
either two depth readings (30-second rate) or four depth readings
(15-second rate) are displayed for each minute during a dive.

(4) Date: This the month and day of the dive.

NiTek He Dive Computer User Manual 39

Using the NiTek He

To view a dive profile:

1. Press button A until “PROF” is displayed.

2. Press button B to enter the profile mode screen.

3. Press button B to scroll “down” through the logged dives. To
fast scroll, press and hold button B.

Note: Once a dive profile is selected, the computer

automatically progresses through the different depths and
times of the dive.

4. When finished, press and hold button A for 1 to 2 seconds to
return to surface mode.

40 NiTek He Dive Computer User Manual

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PC transfer mode

If you purchased the optional personal computer interface for the
NiTek He, you can transfer the stored dive log information to
your PC.

Before transferring the dive log

You must complete the following before transferring the dive
log.

• Install the NiTekLogic software onto your PC. Open the
program > click Options > and check the Uploader tab.
Make sure the COM port selection in the NiTekLogic
software matches the COM port you are connecting to on
your PC.

• Plug one end of the cable supplied with the interface into a
COM port on your PC. Plug the other end into the interface
module.

• Set the NiTek He to PC transfer mode as described below.

• Place the NiTek He on the interface module and secure the
strap over the computer. Click the computer icon in
NiTekLogic. A dialog box should appear indicating the
beginning of data transfer. If it is not uploading, check your
COM port settings.

Notes

• If the dialog box says “negotiating” and cuts off before
saying “transfer,” there is probably a COM port setting issue.
Check to see that you are using the correct COM port.

• If there is an error reported after the dialog box says
“transfer,” check for a loose or dirty connection between the
NiTek He and the interface module.

NiTek He Dive Computer User Manual 41

Using the NiTek He

To enter PC transfer mode:

1. Press button A until “PC” is displayed.

2. Press button B to enter the PC transfer mode screen.
“PC LOAD” is displayed on the screen.

3. Transfer the dive log data to your PC. Follow the
instructions on the previous page.

4. When finished, press and hold button A for 1 to 2 seconds to
return to surface mode.

42 NiTek He Dive Computer User Manual

Using the NiTek He

134

Surface mode (upon surfacing from a dive)

Once you surface from a dive, the NiTek He automatically
switches to surface mode. In addition to the normal information
displayed in surface mode such as time of day, there is other
information that is displayed that pertains to the dive you just
completed. This includes:

• Desaturation time

• Surface interval time

• PGT bar graph

• Oxygen limit index (OLI) bar graph
This information is displayed on both screens until the NiTek He

calculates that it is no longer needed or after 24 hours have
passed since the last dive.

Note: If you are making repetitive dives, you need to pay

attention to your surface interval and use it in conjunction with
plan mode. This ensures that you stay within no-decompression
limits.

2

(1) Surface interval time: This is the amount of time you have
spent on the surface since your last dive if there is residual
nitrogen present from a previous dive. It can display up to 24
hours of surface interval time.

(2) Desaturation time: This is the amou nt of time, expressed in
hours and minutes, that must pass before the residual nitrogen
levels drop to a point where subsequent dives are treated as a
single (non-repetitive) dives. This is not the same as “time to
fly.”

NiTek He Dive Computer User Manual 43

Using the NiTek He

(3) O2 OLI bar graph: This indicates CNS toxicity level at the
end of the dive. This drops as your surface interval time
increases.

(4) PGT exposure bar graph: This is the amount of residual
nitrogen and helium in your body at the end of the dive. This
drops as your surface interval time increases.

WARNING: It is recommended that you wait at least 24-hours

following any dive before flying in an aircraft or driving to
altitude. Failure to allow sufficient surface interval time before
doing so may increase your risk of decompression illness (DCI).

44 NiTek He Dive Computer User Manual

Using the NiTek He

8,530

Altitude operation

The NiTek He adjusts automatically for diving at altitudes of up
to 19,685 feet (6,000 meters). To show that the NiTek He has
made the altitude adjustment, it displays the altitude settings
using symbols representing mountains.

Altitude rank symbols
Symbol Altitude range

No symbol Sea Level to 3,281 feet (1000 meters)

ERR Out of range above 19,685 feet (6,000 meters)

2,297 to 5,906 feet (700 to 1,800 meters)
4,593 to 8,535 feet (1,400 to 2,600 meters)
7,546 to 19,685 feet (2,300 to 6,000 meters)

Prior to using the NiTek He at altitudes substantially above sea
level, you should find out what the actual altitude of your dive
site is. Make certain that the altitude settings the NiTek He
displays accurately match the altitude you are at.

Notes

• Do not use the NiTek He unless the altitude settings
accurately match the actual height above sea level you are
diving in. Doing so could cause the NiTek He to display
inaccurate information.

NiTek He Dive Computer User Manual 45

Using the NiTek He

• Do not use the NiTek He when the “ERR” symbol is
displayed. This means that you are above an altitude of
19,680 feet (6,000 meters), which is beyond the NiTek He’s
ability to function accurately.

• Do not place the NiTek He in dive mode when making
sudden, substantial changes in altitude, such as when flying
in an airplane. This can be caused by storing the NiTek He
with wet dive gear, which can touch its external electrical
contacts and cause it to enter dive mode. This can interfere
with the computer’s ability to function accurately.

The NiTek He monitors and displays altitude information in all
modes, except PC transfer mode. Upon arriving at altitude, the
NiTek He’s PGT bar graph may show that there is excess
nitrogen present, even though you may not have made any dives
in the preceding 24 hours.

If you have obtained the altitude specialty diver training which
everyone should do before diving at altitudes substantially above
sea level, you already understand that this should be expected.
By ascending to a higher altitude from a lower one, your body
has more nitrogen saturated in body tissues than would be
present had you spent the preceding 24 hours at the higher
altitude. By displaying residual nitrogen and a surface interval,
your NiTek He is merely reflecting this fact.

If the level of residual nitrogen calculated by the NiTek He is
unusually high (seven or eight bars) when going to altitude, the
computer will be unable to enter dive mode. Avoid taking the
computer to altitude when residual nitrogen levels are this high,
and do not enter the water until nitrogen levels have dropped
substantially.

46 NiTek He Dive Computer User Manual

Chapter 3

Care and maintenance

Summary

This chapter provides care and maintenance and battery
information for the NiTek He.

Content

Proper handling techniques • 48
Low battery warning • 50

Replacing the battery • 50

NiTek He Dive Computer User Manual 47

Care and maintenance

on in damp 
environment

Cold weather will dim 
LCD dsiplay

Proper handling techniques

The NiTek He is constructed to withstand the most demanding
diving conditions. It is, however, a high precision instrument,
which requires proper care.

Caution: Failure to follow these handling techniques may result

in damage to the NiTek He.

• Do not store the computer in hot and/or humid
environments. The pressure transducer is sensitive to both
heat and humidity. If impaired, it may cause incorrect
altitude or depth readings.

• When in hot and/or humid environments, dip the computer
in water for several minutes to cool it to room temperature
before using it. If it is cold, allow the computer to warm to
room temperature. Do not take it underwater immediately
after doing so.

• Do not transport your NiTek He on an aircraft or take it to
altitude while it is sealed in an air-tight container. Doing so
may interfere with its ability to correctly read, display, and
track depth information.

• The NiTek He’s Liquid Crystal Display (LCD) may darken
if left in a hot environment (such as on a car’s dashboard). It
will return to normal once allowed to cool, however,
extensive exposure to heat may shorten LCD life.

• Be aware that weather-related changes in air -pressure can
cause incorrect display of altitude settings. Be sure to check
indicated altitude settings against actual altitude before use.
Your NiTek He is not to be disassembled by anyone other
than Dive Rite or its authorized dealers. Unauthorized
disassembly will violate the warranty.

• If the NiTek He does not appear to be functioning properly,
do not use it to dive. Return it to your authorized Dive Rite
dealer for repair.

• The NiTek He should not come in contact with solvents or
any type of chemical substances

48 NiTek He Dive Computer User Manual

Care and maintenance

do not store 
submerged in 
water

• Do not use compressed air to dry the NiTek He

• Do not use the NiTek He in hyperbaric chambers if the
device is not fully submerged in water

• Always rinse the computer with freshwater after use

• Store the NiTek He in a cool, dry location. After diving,
wipe the computer dry and store it in a location separate
from other damp items.

NiTek He Dive Computer User Manual 49

Care and maintenance

Seiko states that the battery symbol will blink when battery starts to 
run low and then is on constantly when critical. They also 
recommend to download/record logbook before replacing battery.

Low battery warning

The battery that comes with the NiTek He is designed to last for
up to three years under normal use. You may get more or less
use from the battery depending on how often it is used and how
it is cared for.

Cautions

• All NiTek He functions may cease within two to three days
of the low battery symbol first appearing. Always have low
batteries replaced promptly.

• A depleted battery that is left in a NiTek He for a long period
of time may leak. Replace batteries promptly.

Replacing the battery

Note: Once the low battery warning appears, you must return the

NiTek He to your local authorized Dive Rite dealer for battery
replacement. Be sure to upload or copy all dive log data to your
logbook before replacing the battery.

50 NiTek He Dive Computer User Manual

A

Index

A (mode) button · 11
accessing

modes and screens · 11

alarms · 3

dive time alarm · 18
maximum depth alarm ·

18

algorithm · 5

altitude · 3, 5
altitude operation · 45
altitude symbols · 45
ascent rate warning · 29
ascent time · 32

log mode · 37

B

B button · 11
back light · 4

battery · 5

low battery warning · 50
replacing · 50

Buhlmann · 5

button operation · 11

C

care and maintenance · 47

proper handling

techniques · 48

clock · 5

computer mode · 26

options · 15

computer mode · 15

D

date · 12, 13

log mode · 37

profile mode · 39
date and time · 3
deco symbol · 32
decompression stop

violation warning · 33
decompression warning · 32
default mode · 21

surface mode · 12
default warning · 29
depth · 3, 24, 26

maximum · 26

profile mode · 39

stop depth · 32

depth sensor · 5

desaturation time · 43
descent time

log mode · 37
dive log · 4, 5
dive option set and display

mode · 15
dive profile · 4
dive time · 27

log mode · 37

profile mode · 39
dive time alarm

gauge mode · 22
diving

after a dive · 10

before a dive · 10

during a dive · 10
diving mode · 26

gauge mode · 35

NiTek He Dive Computer User Manual 51

Index

primary screen · 26
second screen · 27

F

features and functions · 3
FHe · 16
FO2 · 16
FO2 and FHe percentages

log mode · 37
fresh or salt water use · 20
fresh water · 16

G

gas mixes · 17

changing underwater · 28
gas mixtures · 3
gauge mode · 35

changing screens

underwater · 35

guage mode · 22

I

Imperial · 4

gauge mode · 22

maximum time alarm · 16,

18
metric · 4
metric or Imperial · 21
mix

changing underwater · 28
mix number · 16

mixes · 5, 17

N

NDL · 24, 27
no-decompression limit ·

24, 27

O

OLI · 27, 44

log mode · 37
options

computer mode · 15
out-of-range warning · 33
oxygen limit index · 27, 44
oxygen limit index warning

· 31

L

log · 4
log mode · 36

viewing · 37

P

PC transfer mode · 4, 41

entering · 42
percentages

mixes · 17
PGT bar graph · 27, 32, 44

M

log mode · 37
PGT limit warning · 31

maximum depth

log mode · 37

maximum depth alarm · 16,

18

52 NiTek He Dive Computer User Manual

plan mode · 24
PO2 · 16, 26
PO2 limit warning · 30
profile · 4

Index

profile mode · 39

viewing · 40

profile sampling rate · 16,

19
gauge mode · 22

R

residual nitrogen · 24, 27,

32, 44

S

safety information · 6
salt or fresh water use

gauge mode · 22
salt water · 16
setting

dive options · 15

fresh or salt water use ·

20

maximum depth alarm ·

18
maximum time alarm · 18
metric or Imperial · 21
profile sampling rate · 19
time and date · 13

size and weight · 5

specificatons · 5
surface interval time · 43
surface mode · 12, 43

entering from another

mode · 12

T

temperature · 28

log mode · 37

thermometer · 5

time

dive time alarm · 18
stop time · 32

time and date

setting · 13
time mode · 13
time of day · 12, 13, 28

W

warnings · 6

ascent rate · 29

decompression stop

violation warning · 33

decompression warning ·

32
default warning · 29
diving mode · 29
low battery warning · 50
out-of-range warning · 33
oxygen limit index · 31
PGT limit warning · 31
PO2 limit warning · 30

water

fresh or salt · 4
salt or fresh water use ·

20

Y

year · 13

NiTek He Dive Computer User Manual 53

Index

54 NiTek He Dive Computer User Manual