SALINITY
45
Note:
A new EC calibration automatically clears the %NaCl calibration. “NO CAL”
message is displayed.
11.3. MEASUREMENT
MW180
supports three seawater salinity scales:
y
Practical Salinity Units (PSU)
y
Natural seawater (g/L)
y
Percentage NaCl (%NaCl)
The required scale is configured in EC MODE SETUP OPTIONS Salinity Scale section.
Note:
These units are for determining salinity and they refer to general use of
saltwater. Practical salinity and natural seawater require a conductivity calibration.
NaCl% requires calibration in MA9066 standard.
PSU – Practical Salinity Units
The practical salinity (S) of seawater relates the ratio of electrical conductivity of a
seawater sample at 15 °C and 1 atmosphere to a potassium chloride solution (KCl) with a
mass of 32.4356 g/Kg water at the same temperature and pressure.
The ratio is equal to 1, and S=35.
The practical salinity scale may be applied to values to through 42.00 PSU at temperatures
between -2 to 35 °C.
