Hach 3700 Series Basic User Manual page 19

Option
CONFIG TDS
CONFIG CONC
TEMP ELEMENT
CELL CONSTANT
FILTER
LOG SETUP
RESET DEFAULTS
(or DEFAULT
SETUP)
Solution Concentration
H PO 0–40%
3 4
HCl 0–18% or 22–36%
NaOH 0–16%
CaCl 0–22%
2
Adjust the T-factor for non-standard cable lengths
When the sensor cable is extended or shortened from the standard 6 m (20 ft), the resistance of the
cable changes. This change reduces the accuracy of temperature measurements. To correct for this
difference, calculate a new T-factor.
Note: This procedure applies only to sensors with a PT1000 temperature element. Sensors with a
PT100 temperature element are less accurate.
1. Measure the temperature of a solution with the sensor and with an independent, reliable
instrument such as a thermometer.
2. Record the difference between the temperature measured from the sensor and from the
independent source (actual).
For example, if the actual temperature is 50 °C and the sensor reading is 53 °C, the difference is
3 °C.
3. Multiply this difference by 3.85 to get an adjustment value.
Example: 3 x 3.85 = 11.55.
Description
TDS only—changes the factor that is used to convert conductivity to TDS: NaCl
(default, 0.49 ppm/µS) or custom (enter factor between 0.01 and 99.99 ppm/µS).
Note: This menu option shows after SELECT MEASURE>TDS is selected.
Concentration (%) only—sets the type of concentration table to use: built-in (default)
or user table (user defined). When built-in is selected, the user can select the
chemical that is measured. If user table is selected, the user can enter up to 10 x,y
(conductivity, %) points in ascending order. Refer to
sc100—This menu option shows after SELECT MEASURE>CONCENTRATION is
selected.
Sets the temperature element for automatic temperature compensation to PT100 or
PT1000 (default). After selection, the user should enter the certified T-factor from the
label on the sensor cable for best accuracy. If no element is used, the type can be
set to manual and a value for temperature compensation can be entered (manual
default: 25 °C).
Note: If a sensor with a PT100 or PT1000 element is set to manual and the sensor is
replaced or the sensor days are reset, the TEMP ELEMENT automatically changes
to the default setting.
Changes the cell constant to the actual certified K value from the label on the sensor
cable. When the certified K value is entered, the calibration curve is defined.
Sets a time constant to increase signal stability. The time constant calculates the
average value during a specified time—0 (no effect, default) to 60 seconds (average
of signal value for 60 seconds). The filter increases the time for the sensor signal to
respond to actual changes in the process.
Sets the time interval for data storage in the data log—5, 30 seconds, 1, 2, 5, 10,
15 (default), 30, 60 minutes.
Sets the configuration menu to the default settings. All sensor information is lost.
Table 6 Built-in concentration tables
Solution Concentration
H PO 0–28%
3 4
HNO 36–96%
3
H SO 40–80%, 93–99% or 0–30%
2 4
HF 0–30%
Table 6.
Solution Concentration
NaCl 0–26%
HBr 0–35%
KOH 0–45%
Seawater 0–5.5%
English 19