ANALOX Sub Mk III F, User Manual

Page: 63 / 79

Sub MkIIIF
User Manual
Int. Approved
Document ref: ASF3-800-08 November 2018 Page 63 of 79
Copyright © 2009 Analox Ltd. All Rights Reserved.
Commercial in Confidence
10.3 Pressure Sensor Calibration
Typical hyperbaric pressure sensors are ranged nominally over 0.8 to 36BarA. It is intended to be
calibrated at two points. Atmospheric Pressure (Cal-L) and a test pressure between 20 and 35
BarA (Cal-H) are ideal for most applications.
The unit requests the two calibration points in the units of measurement used by the instrument.
So for an instrument displaying depth in MSW, the calibration points will be entered as MSW.
Note that the system uses the conversion factors
10MSW = 1 Bar
32.8083 FSW = 1Bar
So 1.00 Bar Absolute is displayed as 0 MSW or 0FSW, and 2.00 BarAbsolute is displayed as either
10MSW or 32.8FSW.
If Cal-L is performed at atmospheric pressure of say 1020mBar, then the Cal-L value should be
specified as 0.20 MSW. Similarly if the atmospheric pressure were 980 mBar, then the Cal-L value
should be defined as -0.2MSW
Typical hypobaric pressure sensors are ranged nominally over 0.1 to 2.0 BarA. Note there is no
conversion available within the system to display in feet altitude, therefore Bar Absolute is the
usual range with such systems. The chart below may assist with calibration of such systems.
Pressure/Altitude Conversion
0.000
0.100
0.200
0.300
0.400
0.500
0.600
0.700
0.800
0.900
1.000
1.100
0 5000 10000 15000 20000 25000 30000 35000 40000 45000 50000 55000 60000
Altitude (feet)
P
res
sure
(
Bar
absolu
te)