How Does The H-Adcp Sample Depth And Pressure; Converting Kpa To Depth - Teledyne WORKHORSE Operation Manual

May 2015
where:
a0 = 9.82697464E1
a1 = -5.86074151382E-3
a2 = 1.60433886495E-7
a3 = -2.32924716883E-12
Pressure Channel:
Pressure sensor internal factory reference points only; no user support.
Attitude Mux Channel:
This channel is multiplexed between the X and Y tilt signals, and the ADC values for this channel in the
output data are therefore not meaningful.
Contamination Sensor:
This data is not used. The readings are generally not consistent.

How Does the H-ADCP Sample Depth and Pressure?

1. For each ping, the ADC samples the pressure sensor five times and averages the data. This is an
attempt to reduce the Standard Deviation.
2. Using the Pressure coefficients, the pressure data from the ADC is converted to kPa.
3. That data is converted to dm and corrected for salinity with the following equation:
Depth (dm) = Pressure(kPa) * (1.02-0.00069*ES), where ES is the Salinity setting.
This is the depth value recorded in the PD0 variable leader when the H-ADCP is fitted with a
pressure sensor and that the EZ command is set to EZx1xxxxx.
4. The pressure data is converted from kPa to deca-Pascals by multiplying it by 100. This value in
deca Pascals is recorded in the PD0 variable leader data.

Converting kpa to Depth

The formula for converting kpa to depth (using WinADCP) is as follows:
(kpa(1.02-0.00069*Salinity)*(1000/Fresh Water Density))/10
Page 212
EAR-Controlled Technology Subject to Restrictions Contained on the Cover Page.
WorkHorse H-ADCP Operation Manual