Cochran EMC-16 User manual

www.divecochran.com
Cochran
EMC-16
Owner's Manual
English - Imperial
Ver: EMC16FO2-3.00
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PRODUCT INTRODUCTION: The EMC-16 is quite simple to use and
operate, but underneath that simplicity lies a significant level of
sophistication. To get the safest and most effective use of this instrument,
it is important that the user fully understand the product. Please read and
understand this entire manual and know the principles and practices of
safe diving before using this device. If you are using the EMC-16 with
Nitrox, the diver specifically acknowledges that he has been adequately
and thoroughly trained and certified to engage in Nitrox diving by a
professional, competent, recognized training agency.
This Manual is divided into the following Sections:
Section Page
•Operation as a One Blend Nitrox Dive Computer 1
•Alarm Clock Operation 3
•Touch Programming 3
•Warnings 6
•Oxygen & PO2 factors 7
•Gas Blend Switching 7
•Configurable Items 9
•Specifications and Maintenance 11
•Liability, and Warranty 12
•Itemized Index and Subjects 14
SIDE CONTACTS:
The Contacts are used to let the user command the unit to do a number of
functions, communicate with a PC for extracting information or configuring
the unit, and determining water conductivity. When Contacts 1 & 2 are
shorted, the EMC-16 can detect the difference between wet fingers, metal
objects, fresh water, salt water, and a PC interface probe.
TURNING ON THE EMC-16:Although the EMC-16 automatically turns on
when it is submerged in water, it is STRONGLY recommended that the
unit be manually powered up by wetting two fingers and simultaneously
touching Contacts 1 and 2 for two seconds. This allows the diver to
ensure that the unit is operating correctly and has adequate battery
capacity prior to entry. Once activated, the unit will remain on for 60
minutes. If a dive is not initiated within this 60 minutes, the EMC-16
automatically shuts off. Notice that when Contacts 1 & 2 are first bridged,
a short beep is issued which indicates that the unit is recognizing the
touch. Every time Contacts 1 & 2 are bridged with wet fingers, the unit will
stay on for one full hour.
The EMC-16 will not turn on if the altitude is greater than 16,000 feet or if
the battery voltage is less than 2.0 volts, or a fault is detected during the
self-test.
As the EMC-16 first recognizes a turn-on command, it begins a
“Diagnostic” function where many aspects of the system will be exercised
and tested. This procedure takes about three seconds and an audible
beep is issued each second as certain tests are successfully completed.
During this time, all of the segments in the display are turned on so that
their operability can be confirmed by the user. Should a test indicate a
malfunction or marginal test, the unit will turn back off again. The user
should ensure that all of the display segments are on and operating
correctly.
TURNING OFF THE EMC-16:After the Post Dive Interval following a
dive, the EMC-16 will remain on for one hour before automatically entering
its "Sleep Mode". During the Sleep Mode, all calculations continue but the
display is off. This is a power saving feature of the EMC-16. The unit will
continue calculating Surface Interval, nitrogen off gassing as required, and
any changes in altitude as it affects Nitrogen Loading. The current Surface
Interval and PreDive Predictions can be viewed by reactivating the unit
MAIN EMC-16 OPERATING MODES:
•Surface Interval (No Nitrogen Residual)
•Surface Interval (With Nitrogen Residual)
•Dive Mode (Normal No Deco)
•Decompression Mode
•Post Dive Interval
•Touch Programming
SURFACE INTERVAL:
After completion of the Self-Diagnostic mode or after the Post Dive Interval
following a dive, the EMC-16 enters the Surface Interval. This period has
two screens, a Primary and an Alternate. To switch to the Alternate
Screen just tap once firmly on the face of the unit. The Primary Screen
displays, if applicable; current Surface Time, the previous dive’s Maximum
Depth, the previous dive’s Bottom Time, Dive of Day number, current Time
to Fly, Altitude and Temperature. The Alternate Screen displays the
Current FO2 (normal Blend) oxygen percentage, current calculated CNS
and OTU values, and current battery voltage. Figure 2 shows the display
with no residual Nitrogen (a clean Dive). Figure 5 shows the display with
residual Nitrogen (a repetitive dive). Figure 3 shows the alternate screen
without residual Nitrogen, figure 6 with.
“Surface Time” starts at zero after a dive and begins counting minutes. If
the computer shuts off and is turned on with Nitrogen residual left, the
Surface Time continues to count. If the computer shuts off and is turned
on with no Nitrogen residual left, the Surface Time will be zero.
1

The “Dive of Day” starts at zero and increments after each dive regardless
of the calendar day. When there is no remaining Nitrogen residual, the
Dive of Day is set to zero and the computer is referred to as a ‘clean’
system.
“Time to Fly” is displayed as the number of hours remaining until the
nitrogen residual reaches zero plus a twelve-hour safety factor. Flying is
not recommended until “Time to Fly” reaches zero.
“Barometric Altitude” is indicated in six ranges via the Ascent Rate Bar
Graph as follows (Altitude compensation is seamless up to 16,000 feet
above sea level). The six ranges are for display purposes only: The
EMC-16 actually senses and computes extremely small altitude changes
and hence, is called “Seamless”. The term “Barometric Altitude” is used
instead of just “Altitude” because the EMC-16 measures Barometric
Pressure to determine Altitude. Barometric Altitude can vary from actual
Altitude by over +/- 1000 feet! What is important to the body when diving
is “Barometric Altitude”.
0 Bars sea level to 2,500 feet
1 Bar 2,500 to 5,000 feet
2 Bars 5,000 to 7,500 feet
3 Bars 7,500 to 10,000 feet
4 Bars 10,000 to 12,500 feet
5 Bars 12,500 to 16,000 feet
DIVE MODE:
Whether in the Surface Interval, PreDive Prediction Mode, Programming
Mode or the Logbook Mode, the EMC-16 will automatically enter the Dive
Mode whenever the unit determines that it is in water deeper than five feet.
On the Primary Screen the Surface time will be replaced with the current
calculated PO2value. Maximum Depth will be replaced with current
Depth, displayed in one-foot increments. Bottom Time will begin once the
EMC-16 senses that the diver has descended below five feet and
continues until the diver has ascended above three feet. The maximum
Bottom Time displayed is 9 hours 59 minutes.
The Alternate Screen will display the current FO2value that the unit is
using in its NDC calculations, the current CNS and OTU values and the
current battery voltage. (Figure 11)
In the Dive Mode the Alternate Screen will display the current oxygen
percentage that the computer is using in the NDC calculations, therefore
after a gas switch the unit will display the Deco Gas Blend oxygen
percentage.
A Depth Alarm which can be set to warn the diver should a certain depth
be exceeded is set at 130 feet from the factory. The Depth Alarm issues
an audible alarm and the “WARNING” legend and Depth Digits will flash
on and off for five seconds. The depth alarm is disabled if in the
Decompression Mode since flashing depth digits have another meaning in
this Mode.
The maximum depth achieved on the current dive is shown as “MAX
DEPTH”. This is updated once per second.
“REMAIN TIME” (NDC) is the remaining time (in hours and minutes) that
the diver can stay at the current depth without requiring decompression. A
“Two Minute Warning” will be issued when this time reaches two minutes
or less. An audible alarm will be issued and the “WARNING” legend and
“REMAIN TIME” digits will flash. By immediately ascending to a shallower
depth, the diver may avoid a required decompression stop.
Temperature is measured for two purposes. One is to compensate the
Depth Transducer for Temperature variations. The other is to compensate
the Nitrogen algorithm for changes in Temperature that may affect the
body. Both of these purposes require that the Temperature be very slow
reacting, just like the Depth Transducer and the body. This slow-reacting
Temperature is what is displayed. For Temperature effects on the body,
the amount of compensation can be set from NORMAL to REDUCED with
the Analyst® PC software Interface (see Analyst® Section), if the diver is
using a good dry-suit in cold water. Temperature compensation starts at
75 degrees F and gets progressively more conservative as the
temperature decreases. There is no compensation above 75 degrees F.
Bottom Time will begin once the EMC-16 senses that the diver has
descended below five feet (see Training Mode) and continues until the
diver has ascended above three feet. The maximum Bottom Time
displayed is 9 hours 59 minutes.
ASCENT RATE BAR GRAPH:
The Ascent Rate bar graph and alarms are active in both the Dive Mode
and Decompression Mode. The five-segment bar graph is used to display
the diver's rate of ascent.
Via the Analyst®PC Interface, the Ascent Rate Alarms and Bar Graph can
be set to the users preferences.
The first option is a VARIABLE-BY-DEPTH Ascent Rate. When “on”, the
Ascent Rate Alarm is determined by depth. As the diver ascends to
shallow depths, the Maximum Ascent Rate is lowered. The Maximum
Ascent Rates and their associated depth are:
60 feet or deeper 60 feet per minute
60 to 30 feet feet per minute equal to the depth
Less than 30 feet 30 feet per minute
If VARIABLE-BY-DEPTH is off, the Maximum Ascent Rate Alarm and Bar
Graph is specified by the user and can be from 20 to 60 fpm, in one foot
increments.
Another selection is the bar graph itself. The two selections are either
FIXED or PROPORTIONAL.
With FIXED, each of the five bars indicates an additional 10 feet per
minute of Ascent Rate regardless of the Maximum Ascent Rate selected.
With PROPORTIONAL, each of the five bars indicates 20% (one-fifth) of
the selected Maximum Ascent Rate.
For FIXED, the maximum ascent rate is 60 feet per minute. With this
setting, no bars will illuminate if a diver is ascending at a rate less than 10
feet per minute.
If the diver has an Ascent Rate that exceeds the selected maximum, the
entire Ascent Rate Bar Graph will flash, and the audible alarm will sound
once per second, and the WARNING legend will illuminate.
The sensitivity or responsiveness of the Ascent Rate may be selected via
the Analyst®, eight different levels of sensitivity are available.
NOTE: Customizing the Ascent Rate and Ascent Rate Bar Graph are
among many of the additional programmable features available when
using the Analyst®PC Interface. Available features are described in the
section “USER CONFIGURABLE OPTIONS”.
As shipped from the factory, the Ascent Rate is set for VARIABLE-BY-
DEPTH AND PROPORTIONAL.
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DECOMPRESSION MODE:
Should a no-decompression limit be overstayed, the EMC-16 will enter the
Decompression Mode. In this mode, the Ceiling digits will display the
depth at which the diver must stop and not ascend above during final
ascent. The “TEMP” legend and two digits will be replaced with the “CEIL”
legend and two digits. The Ceiling will start at 10 feet and increase in ten-
foot increments as the diver remains at a relatively deep depth.
The Remaining No-decompression Time and “NDC” legend will be
replaced with Decompression Time and “DEC” legend (Figure 16d). Both
STOP time and TOTAL time are displayed in the upper left hand three
digits of the screen in hours and minutes. STOP and TOTAL time will
alternate at the rate of once every two seconds. In this way, the diver can
view the time to spend at a particular STOP depth, and the TOTAL time it
will take to complete all STOPS. Clearly, the larger of the two alternating
numbers is the Total Decompression Time of all stops, and the smaller of
the two numbers is the time required at the current stop. At the ten foot
stop, the TOTAL and STOP times may be the same and therefore appear
to not alternate.
When at a specific stop, the required decompression time at that stop is as
shown, and will appear to count down as it is recomputed every second,
based on the divers exact current depth. The Decompression times (both
Stop and Total) are accurate only if the diver’s depth is exactly the same
as the required Ceiling. However, it is not necessary to be precisely at
that specified Ceiling. Appropriate In-gassing or Out-gassing will be
computed regardless of the diver’s current depth.
A small margin shallower than the Ceiling also exists. Should a Ceiling be
‘violated’ (diver is shallower than Ceiling), the “WARNING” legend will
illuminate and flash along with the Depth and Ceiling digits. An Audible
alarm will sound once every two seconds. This warning will continue until
the Depth has been corrected. Out-gassing will continue even though the
diver is shallower than the Ceiling. There is no ‘Gauge’ mode or ‘Lockout’
on the EMC-16.
If the diver surfaces before satisfying his decompression obligation, the
EMC-16 will continue to give out-gassing credit as if it were in a dive, but
at a depth of zero feet and will satisfy the decompression time
requirements of the required stops using an FO2of 21%. The unit will
continue to log data and perform as if actually in a dive. When the
decompression obligation is finally satisfied, the ten-minute “PostDive
Interval” will begin.
Several seemingly ambiguous situations may occur with the Deco
Forecast ‘enabled’, they are:
•Satisfying Deco Stops during ascent.
•The Deco Gas Switch may occur early or late.
•Forecast Deco Stop time & depths may switch up/down/up/down as
the diver ascends due to the in-gassing and out-gassing of the
different ‘controlling’ tissue group.
NOTE: COCHRAN does not intend for this instrument to be used for
deliberate Decompression diving.
POST DIVE INTERVAL:
During the first ten minutes (or up to thirty minutes if the unit is in the
Training Mode) after a dive, the EMC-16 is in the Post Dive Interval. The
flashing "SURF" legend and a Surface Time of less than ten minutes (or up
to thirty if the unit is in the Training Mode) indicate this. Should another
dive be commenced before the completion of the Post Dive Interval, that
dive will be considered an extension of the previous dive. In this case,
Bottom Time will NOT include the time spent on the surface in this Post
Dive Interval. However, when reviewing the profile with the Analyst®, the
time spent on the surface in this period will be shown. In the case were the
unit has performed a gas switch; while in the Post Dive Interval the
Alternate Screen will display the Oxygen percentage of the Deco Gas
Blend and if the diver re-enters the Dive mode the unit will perform its’
calculations based on the Deco Gas Blend Oxygen percentage until the
diver descends below the Gas switch Depth. Below this depth the unit will
revert to the Normal Gas Blend for the NDC calculations.
CONFINED WATER PROTOCOL (Training Mode): The EMC-16 is one of
the first dive computers to offer an operating mode designed to record and
store data from training dives. That is, dives performed in shallow water
environments (swimming pools, shallow lakes, lagoons, etc.) or calm open
water environments that have less than 1-foot seas. In the Training Mode,
the EMC-16 enters the Dive Mode at a depth of 2 feet instead of 5 feet and
will exit the Dive Mode at 1 foot instead of 3 feet. Also the Post Dive
Surface Interval may be extended, via the Analyst®from10 minutes up to a
maximum of 30 minutes in 1-minute increments after which the dive data is
stored in the computer's memory. These changes permit the Instructor to
record the complete training session, including in-water surface periods, as
a single dive. The Training Mode can only be enabled/disabled via the
Professional Edition of the Analyst®PC Interface.
TACLITE™: The EMC-16 is equipped with the TACLITE™ tactical low-
light fiber-optic backlighted display. The standard TACLITE™ color is night
vision safe red, but it is also available in yellow for those individuals who
have vision difficulties with the color red. The TACLITE™ can be activated
on demand. To turn the TACLITE™ on, tap the face of the EMC-16 and
the TACLITE™ will turn on for the preprogrammed number of seconds (1
to 98), then turn off. By tapping the face again the TACLITE™ will turn on
again. In this fashion the TACLITE™ can be kept on for as long as
wanted. If 0 is entered, the TACLITE™ will never turn on. If 99 is entered,
the TACLITE™ will stay on continuously and only turn off when the EMC-
16 does. The number of seconds that the TACLITE™ stays on can be set
via the Programming Mode or via the Analyst®PC Interface, factory setting
is 10 seconds. The TACLITE™ will turn off when the EMC-16 turns off. If
the batteries get too low, the TACLITE™ will turn off and cannot be turned
back on until fresh batteries are installed.
3

CLOCK MODE: The Clock operating mode of the EMC-16 is NOT
enabled when shipped from the factory. It can be enabled via the Analyst®
P.C. Interface or at an Authorized Cochran Dealer.
TOUCH PROGRAMMING MODE: Can only be accessed when the unit is
in the Surface Interval and allows the user to view or program into the dive
computer:
•Setting Clock and Alarm Time
•The PreDive Prediction Mode
•Displaying Mode, mode value, CNS, OTU & battery voltage
•A Maximum Depth Alarm
•An Added degree of Conservatism from 0 to 50%
•Setting oxygen percentage of blend 1 in the Constant FO2Mode
•Setting the Deco FO2oxygen percentage
•Setting the Deco Bottom Time Benchmark
•Setting the Deco Depth Benchmark
•Programming the On Time for the TACLITE™
•Access the Logbook Mode
While all EMC-16 configurations share certain programming features
others are dependent upon the specific configuration of the unit.
Refer to the appropriate manual section for the relevant programming
menu items.
TOUCH PROGRAMMING - CLOCK: When the EMC-16 is placed into the
Clock mode it will display the time of day in a 24 hour day format. The
clock will continue to run when the EMC-16 is in the Dive Computer Mode.
The EMC-16 can be placed into the Clock Mode from the Dive Computer
Mode when the unit is in the Normal Surface Interval, while the unit is in
Clock Mode the Dive Computer will be in the “Sleep” mode.
The Clock Mode can be selected with or without an Alarm. If the Alarm
option is selected the unit will display the alarm set time as well as the
current time.
When the alarm time is displayed the alarm is activated and at the
programmed time the alarm will sound once every 24 hours. When the
alarm is activated the unit will issue a medley of all the audible warning
tones that the EMC-16 utilizes and the TACLITE™ will flash for one
minute, this audible alarm can not be turned off, it will sound for the full
one minute period.
NOTE: This Time of Day clock is the same clock that is used to time
stamp dives. Modifying the Time of Day clock will effect the Local
Time as viewed via the Analyst®. The Date portion of the Local Time
clock must be changed via the Analyst®.
CLOCK PROGRAMMING PROCEDURE:
Contacts 1, 2, & 3 are for programming sequences.
To begin the programming sequence:
1. Turn the unit on;
2. Using a coin or other conductive metal object, briefly bridge Contacts
1 and 2 until a short beep is heard and the CLoCk Menu is seen on
the display.
3. To enter the Clock submenu, bridge Contacts 1 & 2 with wetted
fingers. This will cause the unit to display the CLoCk Alarm selection
– On or OFF. To Toggle the selection, bridge contacts 1&2 with
wetted fingers.
4. Using a coin or other conductive metal object, bridge Contacts 1 & 2
to access the CLoCk Time or Alarm setting screen.
5. Shorting Contacts 1 & 2 with a coin will cause the first digit of the
minutes to flash.
6. Shorting Contacts 2 & 3 with a coin will increment the numeric value;
continue until the required value is displayed. A confirmation beep
will sound with each increment.
7. Next using wetted finger, bridge Contacts 1 & 2 to select the next
digit, once selected the digit will flash to identify that it is being
programmed. Bridge Contacts 2 & 3 till the desired value is
displayed.
8. To select Hours short Contacts 1 & 2 with a coin, increment as in step
6 and 7.
9. Repeat step 5 through 7 until all digits have been programmed.
10. To save the changes that have been made bridge Contact 1 & 2 with
a coin or other conductive metal object. Once the next programming
option is displayed the changes have been saved.
To exit the Clock Mode Bridge contacts 1 & 2 with wetted fingers and the
computer will return to the Dive Computer Mode’s Surface Display.
NOTE: Ensure that the EMC-16 is in the Dive Computer Mode before
commencing a dive.
Figures 40, 41a, 41b, 42 and 43 show how the Clock display screens
appear.
NOTE: Once the EMC-16 is placed in Clock Mode the unit will remain
in that mode until exited by the diver.
TOUCH PROGRAMMING MODE:
NOTE: To enable the Programming Mode, the EMC-16 must be on the
Surface and not in the Post Dive Interval.
NOTE: All audible and visual alarms are suspended while the EMC-16
is in the Programming Mode. Upon exiting the Programming
Mode all alarms are reactivated.
NOTE: Once a value has been changed and the next menu option
selected, the new value is stored.
NOTE: It is strongly recommended that the Programming Mode is
activated again and a complete review of what was stored is
accomplished.
NOTE: If the EMC-16 is left in the Programming mode for five minutes
without the contacts being touched, the unit will automatically
exit the Programming Mode and return to the Surface Interval.
Once this occurs the EMC-16 will retain the modified
programmed settings that have been stored. Options that
have not been modified will retain their previous settings.
TOUCH PROGRAMMING MODE - PROCEDURE:
Contacts 1, 2, & 3 are for programming sequences.
To begin the programming sequence:
1. Analyze the gas blend(s) using a calibrated Oxygen Analyzer.
2. Turn the unit on.
3. Using a coin or other conductive metal object, briefly bridge Contacts 1
and 2 until a short beep is heard and the Programming Menu is seen
on the display. The menu options depend on whether the unit is
activated for the Clock, and the number of Gas Blends. The Menu
options are displayed in sequence, incrementing to the next selection
each time that Contacts 1 & 2 are bridged with a coin. The program
option is displayed on the upper row of the display. The current setting
for this option is displayed in the lower right of the display.
4

4. To reprogram the displayed menu values, bridge Contacts 1 & 2 with
wetted fingers. This will cause the current setting to flash or in the
case of multi-digit numbers, the least significant digit will flash. The
clock will toggle between on and off.
5. Using a coin or other conductive metal object, bridge Contacts 2 & 3 to
increment the numeric value. A confirmation beep will sound with
each increment.
6. Next using wetted finger, bridge Contacts 1 & 2 to select the next digit,
once selected the digit will flash to identify that it is being programmed.
Bridge Contacts 2 & 3 till the desired value is displayed.
7. Repeat step 5 until all digits have been programmed.
8. To save the changes that have been made bridge Contact 1 & 2 with a
coin or other conductive metal object. Once the next programming
option is displayed the changes have been saved.
All programming sequences use the same routine of using Contacts 1 and
2 to SELECT the next programming sequence and Contacts 2 and 3 to
INCREMENT the specified value.
PROGRAMMING MENU
The ANALYST®Personal Computer Interface allows the user to enable or
disable the second gas mix; the following table lists the various
programming choices with their display identification and figure number
using two gas mixes.
Identification Description Figure Page
CLC Clock - if enabled 40 4
PdP PreDive Prediction 22 7
InF Misc. Information 23 7
dEP AL Depth Alarm, Max value is 320 feet. 25 7
Con Added Conservatism, Max value is 50%.26 7
EAn 1 Oxygen percentage of Blend,
Allowed value 21 to 50. 27 7
EAn 2 Deco FO2 Oxygen percentage,
Allowed value 21 to 99.9. 28 7
dEC b Bottom Time Benchmark for Deco
FO2 switching, Allowed
value 10 to 999 minutes.29 7
dEC d Depth Benchmark for Deco FO2
switching, Max value is 99 feet. 30 7
TAc dL TACLITE™ On Time
Allowed value 00 to 99. 33 7
LOG Logbook 34a 7
TOUCH PROGRAMMING - PREDIVE PREDICTION:
PreDive Prediction is accessed via the Touch Contact Programming
Menu. This enables the diver to view the PreDive Prediction information at
the touch of the Contacts. During the PreDive Prediction Mode, the unit
will compute and display the maximum safe time and the calculated PO2
value at that depth. The EMC-16’s PreDive Prediction starts at 30 feet
and increases in 10 feet increments. PreDive Predictions will terminate
when the No-Decompression (NDC) time prediction reaches two minutes
or a maximum depth of 320 feet is reached. Additional Conservatism,
Residual Nitrogen, blend #1 oxygen percentage and Barometric Altitude
can affect PreDive Predictions. Once the maximum PreDive Prediction
depth has been reached the unit will return to the Surface Interval.
TOUCH PROGRAMMING - INFORMATION DISPLAY:
The InFormation display is accessed via the Programming Mode. The
information presented will depend on the configuration of the dive
computer. The information in the upper right of screen indicates the unit is
in the Constant FO2 Mode and the number of gas blends the unit is
enabled for. The following table lists the identification and the description.
Identifier Description
F0 Air only
F1 Single Blend Nitrox, 21 to 50%
F2 Two Blend Nitrox, 21 to 50% and 21 to 99.9%
Battery voltage is displayed in the lower center of the screen as a two-digit
number with a decimal point. The screen will display the current CNS,
OTU and battery voltage. The current CNS exposure level is displayed on
the lower left as a two-digit number proceeded by a lower case “c”. The
current OTU value is displayed on the lower right again as a two-digit
number but preceded by a lower case “o”. Both the CNS and OTU values
are expressed as percentages. Figure 24a displays a typical InFormation
screen for a unit that is enabled for two nitrox blends.
TOUCH PROGRAMMING - DEPTH ALARM: The Depth Alarm allows the
diver to select a maximum depth below which the diver does not wish to
descend before an alarm is issued. This depth can be set from 0 to 320
feet in one foot increments.
TOUCH PROGRAMMING - CONSERVATISM: This programming function
allows the diver to input an added degree of Conservatism into the EMC-
16’s nitrogen algorithm. Via Touch Programming the Conservatism can be
set from 0 to 50%.
TOUCH PROGRAMMING - BLEND #1:
The oxygen percentage of Blend #1 can be programmed from 21.0% to
50.0%. Once programmed the oxygen percentage will remain at the value
programmed until changed by the user.
5

TOUCH PROGRAMMING - BLEND #2: The oxygen percentage of Blend
#2 can be programmed from 21.0% to 99.9%. Once programmed the
oxygen percentage will remain at the value programmed until changed by
the user.
TOUCH PROGRAMMING - BLEND #2 - TIME BENCHMARK: The Blend
#2 (Deco) Time Benchmark can be programmed from 10 to 999 minutes.
Once programmed the time benchmark setting will remain at the value
programmed until changed by the user.
TOUCH PROGRAMMING - BLEND #2 - DEPTH BENCHMARK: The
Blend #2 (Deco) Depth Benchmark can be programmed from 0 to 99 feet.
Once programmed the depth benchmark setting will remain at the value
programmed until changed by the user.
TOUCH PROGRAMMING - TACLITE™: The Taclite™ dwell (on) time
can be set so that when the face on the EMC-16 is tapped the Taclite™
will stay on from 1 to 98 seconds. If the dwell time is programmed to ‘0’
the Taclite™ will never come on, if programmed to 99 the Taclite™ will be
on whenever the EMC-16 is awake.
TOUCH PROGRAMMING - LOGBOOK MODE: The Logbook of the
EMC-16 has two screens, a Primary Screen and an Alternate Screen. To
switch to the Alternate Screen just tap firmly on the face of the unit. The
Logbook is accessed via the Touch Contact Programming (see page 4).
This enables the diver to view dive statistics; the EMC-16 has the ability to
provide diving data for the most recent 1024 dives. The most recent dive
will be displayed first. To view the next dive, touch the contacts 1 & 2 with
wetted finger after pausing for a few seconds. Do not use a metal object
such as a coin or knife-blade once in the Logbook since it will cause the
unit to exit the Logbook and return to the Surface Interval.
Information contained in the Logbook will include:
Overall Dive Number Minimum NDC Time
Fastest Rate of Ascent Minimum Water Temperature
Bottom Time Surface Interval Before Dive
Maximum Depth Ending Battery Voltage
Maximum DEC Time (Deco Dive) Maximum Ceiling (Deco Dive)
It is not necessary to exit the Logbook Mode prior to initiating a dive. Once
the diver has descended below five feet, the EMC-16 will immediately
enter the Dive Mode.
NOTE: The overall Dive Number that is displayed on the Logbook Menu
screen (Figure 34) permits the diver to identify the total number of dives
made with that EMC-16. If the logbook example shown is the most recent
dive made, it can be readily identified that 235 dives have been made with
this specific unit.
Figures 35 & 37 display the Logbook of a Normal Dive.
While Figures 36 & 38 display that of a Deco Dive
6

WARNING INDICATIONS: Failure to observe audible and/or visual
warnings and take corrective action may result in injury or death. In
general, if the WARNING legend is flashing, some other digits should be
flashing to indicate the anomaly.
•If the diver is ascending faster than the selected maximum ascent
rate, then the top bar of the ascent bar graph will flash and the
“WARNING” legend will illuminate. The unique high to low audible
sweep alarm will continue to sound once per second until the
situation is corrected.
•If the diver descends below the user set Depth Alarm, the Depth
digits will flash. A single beep audible alarm will sound once per
second for five seconds and will repeat every two minutes. The
Depth alarm is not active in the Decompression Mode to avoid
confusion with the “Shallower Than Ceiling” alarm.
•If the battery voltage goes below 2.5 volts, the “BATT” legend will
illuminate, at 2.2 volts it will flash once per second.
•If the diver has less than two minutes of No-Decompression Time
(NDC) remaining, the “WARNING” legend will illuminate and flash
along with the Remaining NDC time digits. A single beep audible
alarm will sound once per second for five seconds and repeat every
two minutes.
•If the diver enters the Decompression Mode, a single beep audible
alarm will sound once per second for five seconds.
•During a Decompression dive, if the Depth is less than the CEILING,
the “WARNING” legend will illuminate and flash along with the Depth
and Ceiling digits. A unique high to low audible sweep alarm will
continue to sound once every two seconds until the situation is
corrected.
•If the dive computer determines that either the Depth or Temperature
sensor is malfunctioning. The “WARNING” legend will illuminate, the
computer will also issue a 5-beep two tone audible alarm once every
two minute to alert the diver to this condition. On the Appropriate
Screen the Maximum Depth will be replaced with “S-d“ or "S--" to
indicate the low-pressure transducer or “S-t” for the temperature
transducer.
•For High PO2, see “OXYGEN TOXICITY FACTORS” on page 7.
•For High CNS, see “OXYGEN TOXICITY FACTORS” on page 7.
•For High OTU, see “OXYGEN TOXICITY FACTORS” on page 7.
If an audible alarm is being issued, the computer will not switch to the
Alternate display nor will the TACLITE™ activate.
SENSOR WARNING: The EMC-16 has the capability of monitoring the
integrity of its' sensors, both the low-pressure (depth/altitude) and the
temperature. When the computer detects an error in one of the
transducers, the diver is alerted to this condition by the illumination of the
“WARNING” legend, and the computer will also issue a 5-beep two tone
audible alarm once every two minute to alert the diver to this condition.
The Maximum Depth will be replaced with “S-d“ or "S--" to indicate the low-
pressure transducer or “S-t” for the temperature transducer (see figure
18a). The “WARNING” legend, along with either the Temperature digits or
the Depth digits and the error code will flash once per second. In the
highly unlikely situation were both sensors are detected as having errors,
the display will alternate between “S-d“ or "S--" and “S-t”. This warning will
be issued whether the computer is in the Surface Interval, Dive Mode,
Decompression Mode or Post Dive Interval. In the unlikely case that your
computer issues one of these warnings the unit should be returned to the
factory for evaluation and/or repair.
Figure 18a shows a Sensor Warning, in this case a Temperature Sensor,
as it would be displayed in the Dive Mode. If the Sensor Warning was for
the depth sensor it would display “S-d“ or "S--".
OXYGEN TOXICITY FACTORS: The EMC-16 has the ability to track
Oxygen Toxicity levels for the Central Nervous System (CNS) as well as
the Mission Oxygen Tolerance Units Dose (OTU). In addition, a maximum
Partial Pressure of Oxygen (PO2) warning alarm can also be set. While
most other audible alarms of the dive computer consist of five long beeps,
the CNS, OTU, and PO2have a distinctive audible alarm that consists of
short double-beeps that sound once per second for five seconds.
As long as one or more of these three parameters is outside its limits, the
“WARNING” legend on the display will continue to flash and the audible
alarm will be repeated once every two minutes.
These three functions are not active if the NITROX capability is disabled
via the Analyst®PC Interface.
PARTIAL PRESSURE OF OXYGEN (PO2): High levels of PO2can cause
severe Oxygen poisoning. Individual divers can be affected by widely
different levels of PO2. The user via the Analyst®can set the PO2alarm to
any level between 0.50 ATA and 1.59 ATA. As shipped from the factory,
this is set to 1.40 ATA. Should the PO2be above the alarm set point, the
“WARNING” legend will illuminate and the audible alarm will sound and the
PO2value that is displayed will flash.
CENTRAL NERVOUS SYSTEM (CNS) TOXICITY: The user via the
Analyst®can set the CNS Toxicity alarm to any level between 40% and
80% of the maximum allowable limit. As shipped from the factory, this is
set to 50%. Should the CNS Toxicity reach 50% of the maximum
allowable, the “WARNING” legend will illuminate and the audible alarm will
sound and on the Alternate Screen the displayed CNS percentage will be
flashing along with the “WARNING” legend.
By the accepted definition of CNS toxicity, should a PO2value of greater
than 1.6 ATA be measured, the CNS Toxicity will be 100%. During the
Surface Interval, this percentage will decrease as the CNS declines toward
zero. Whatever the current CNS Toxicity level, it can also be viewed on
the Surface Interval Alternate Screen or on the InFormation screen in the
Programming Mode.
OXYGEN TOLERANCE UNITS (OTU): An issue with long term breathing
of higher partial pressures of Oxygen above 0.5 ATA is Pulmonary Oxygen
Toxicity or sometimes called WHOLE BODY which must be tracked
properly.
The EMC-16 will track the OTU based on Dr. Bill Hamilton’s ‘REPEX’
method of oxygen exposure management. The OTU Dose is an
exponential function of oxygen partial pressure and time.
The time-dependent limit varies with length of time (days) that the diver
continues to dive without full recovery to zero OTU. The Mission OTU
Clock tracks the OTU, which is a running clock that tracks long-term
Oxygen exposure. This clock may run for several weeks if frequent dives
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are made using high levels of PO2. The current Mission Clock, CNS, and
OTU can be seen via the Analyst®PC interface or the current CNS and
OTU values can be viewed on the Alternate Screen while in the Surface
Interval, Dive Mode, Decompression Mode or Post Dive Interval. The
current CNS and OTU values can also be viewed via the Touch Contact
Programming mode by selecting the InFormation option. The recovery
portion of the OTU algorithm is a linear reduction of OTU over time. The
Mission OTU clock is reset to 0:00 when the OTU Dose reaches zero.
The user via the Analyst®can set the OTU Toxicity alarm to any level
between 40% and 80% of the maximum allowable limit. As shipped from
the factory, this is set to 50%. Should the OTU Dose reach 50% of the
maximum allowable, the “WARNING” legend will illuminate and the audible
alarm will sound and on the Alternate Screen the displayed OTU value will
be flashing along with the “WARNING” legend.
Symptoms of Pulmonary Oxygen Toxicity include burning in the throat and
chest, coughing, and shortness of breath. Discontinue diving and consult
a Physician should any of these, or other, symptoms appear.
Figure 39 shows a CNS exposure over the alarm set point (50%), in the
situation were both the CNS and the OTU exposure was over their set
points both values would flash.
EMC-16 – USING TWO GAS NITROX
OVERVIEW: The EMC-16 is capable of being used for two different Nitrox
mixtures on the same dive. The first gas or Normal Blend is
programmable from 21% to 50% Oxygen in 0.1% increments while the
Deco Blend can be programmed from 21% to 99.9% Oxygen again in
0.1% increments. Both Blends are set at the factory to 21% Oxygen and
use this in its decompression algorithm. PRIOR to diving an Enriched Air
Nitrox gas blend, the unit must be programmed accordingly. This can be
done via the Touch Contacts or via the Analyst®PC Interface.
GAS BLEND SWITCHING: While most other Nitrox dive computers limit
the diver to the use of a single gas blend or percentage of oxygen, the
EMC-16 allows the diver to use two different gas blends during a dive.
These two gas blends are commonly referred to as the Normal or Bottom
Gas Blend and the Decompression Gas Blend. Commonly, the Bottom
Gas Blend is used from initial entry into the water and for most of the time
spent during the dive. The Normal Gas Blend is restricted to a maximum
of 50% oxygen. The Decompression Gas Blend (Deco Blend) is used only
for decompression purposes and can go to 99.9% oxygen content.
Typically, the Deco Blend is in a cylinder that is suspended at some
relatively shallow depth beneath the surface.
Since the depth of the Deco Blend switch is known ahead of time, and the
expected duration of the dive is also known, these two factors can be used
to automatically switch the computer to the Deco Blend or back to the
Normal Blend should the diver descend again. This is accomplished prior
to starting a dive by specifying both the Normal Gas Blend Oxygen
percentage and the Deco Gas Blend Oxygen percentage. The depth of
the Deco switch is also specified. Depending on surface swells, a few feet
may be added to this depth to ensure that when the diver is shallower than
the depth the Deco Blend will actually be in use. If the diver subsequently
descends below this depth, the Bottom (Normal) Blend is again assumed
to be in use. The other important factor that must be specified is the
Bottom Time that must elapse before Blend Switching is enabled. The
purpose of this factor is to ensure that the switch to the Deco Blend does
not occur prematurely should the diver ascend early and not require use of
the Deco Blend, the setting of this factor must be carefully considered.
The Deco Blend switch is enabled when the diver descends below the
switch depth and satisfies the time requirements and then ascends to the
programmed switch depth. If the diver does not exceed the programmed
switch depth the unit will not switch to the Deco Blend. All of these factors
can be set by either the touch contact programming or via the Analyst®PC
interface. If switching to the Deco Blend is NOT desired, it may be
disabled via the Analyst®. Setting both Blends to the same percentage of
Oxygen is the same as disabling the Deco Blend.
TOUCH CONTACT PROGRAMMING SCREENS: The following are all of
the screens that the EMC-16 is capable of presenting in the Touch
Programming Mode. Refer to the particular configuration for appropriate
screens.
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