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 PO
2
value. 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 FO
2
value 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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