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Model T80
Press NO
With the sensor in the process solution
Press STAND
Enter the laboratory determined conductivity value
Press
▲
▼
NEXT
xxx.xx MΩ (use arrows and NEXT to enter process value)
Press OK
Current Value xx.xx MΩ, Desired Value: xx.xx MΩ, Offset XX.XX OK?
Press OK
Back to Cal Menu
Press Home
Hold is ON (Press HOLD to turn off Hold)
Press HOLD
Turn off Hold
Press EXIT
Main Display
4.10
S
ALINITY
(P
RACTICAL
S
ALINITY
S
CALE
)
Practical Salinity, symbol S, of a sample of seawater, is defined in terms of the ratio K
15
of the electrical
conductivity of the seawater sample at the temperature of 15°C and the pressure of one standard atmosphere,
to that of a potassium chloride (KCl) solution, in which the mass fraction of KCl is 32.4356g per kg of solution, at
the same temperature (15°C) and pressure (1 atm). The K
15
value exactly equal to 1 corresponds, by definition, to
a practical salinity exactly equal to 35. The conductivity of 32.4356g of KCl per kg of solution is 42.914 mS at 15°C
and 53.64 mS at 25°C.
Calibration of the conductivity sensor is slightly different than a standard S80 conductivity calibration. Most
calibrations are referenced to the value at 25°C, this calibration is referenced to the conductivity value at 15°C.
Since the temperature correction for conductivity is 2% / °C, the calibration solution value is 80% of the standard
value at 25°C, 50 mS @25°C solution is entered as 40 mS.
2%/°C x (25°C - 15°C) = 20% correction so 50 mS x 0.80 = 40 mS
Use the PSU Calibration solution 42.914 mS (PN 2010086) or use another Conductivity Standard and correct the
value to the value at 15°C.
Action
Prompt
Double Press any Button
MENU HOME, Hold is OFF
Press HOLD
Hold freezes 4-20 mA Output and locks Alarm Relays during Calibration
Press CAL
Is this a new Sensor? (Yes erases CAL Log in INFO, NO adds CAL to existing Log)
Press Yes/NO
Remove the Sensor from Solution and dry the front end, Air = 0.00 µS
To perform zero CAL press CAL 1, to skip zero CAL press CAL 2, only if a zero CAL was previously done on the sensor
Press AUTO then CAL 1
STABILIZING, 0.00 µS, 1.17 V, 0.00 µS corrected, Accept Cal?
Press YES
CAL 1 Value 0.00 µS, Continue to CAL2? Move sensor to 42.91 mS solution
Press YES
STABILIZING, 53.64 mS, 200.0 mV, 50.00 mS corrected value, Accept Cal?
Press NO
Enter the temperature corrected value
Press
▲
▼
NEXT
42.91 mS or Temperature Corrected value (use arrows and NEXT to enter process
value)
Press OK
42.91 mS, 200.0 mV, Accept Value?
Press OK
OFFSET: 0.00 ppm, 1.17 V, SLOPE: 784 (data written to Log)
Press OK
Calibration complete
Press HOME
Hold is ON
Press HOLD
Turn off Hold
Press EXIT
Home Screen 35.0 PSU
