Hach Orbisphere 51 Series User Manual Download

Page: 54 / 118

Measurement Menu

K1200 sensor

•

Sensor

: Sensor model.

•

Medium

: Liquid or gas phase.

•

Gas unit type

: Partial, Fraction, Dissolved.

•

Gas unit

: The list of available units depends on unit type selected above.

Note:

This is the gas concentration measured by the sensor. When a composite unit is selected (e.g.

ppm-ppb) the unit will change depending on the range of the value to display.

•

Liquid

: For the K1200 sensor this option is locked on water.

•

Display resolution

: Maximum resolution depends on gas, membrane and unit. A maximum of 5

digits can be displayed. Decimals can be limited to 0, 1, 2 or 3 decimals for easier reading. That does
not affect the actual resolution of data measured and stored, but only the data displayed.

•

Thermal cutoff

: To protect the sensor, the thermal cutoff function allows for setting a sample high

temperature limit. If exceeded (during a Cleaning In Place cycle for example) the electrical signal to
the sensor is cut off, the measurement session is suspended and the system displays a “HOT” alarm
message. The system resumes when temperature drops to 90% of the specified cutoff temperature.

•

Thermal cut off

: It is recommended to enable this feature to maximize sensor life and system

performance.

•

Thermal cut off temperature

: Set to 5°C above sample temperature e.g. if sample temperature

is 2°C, set thermal cut-off to 7°C.

Advanced configuration - K1200 sensor

Important Note:

The offset feature described below should be used for minor measurement adjustments

only, and not as an alternative to a sensor calibration. Make sure your sensor has been correctly
calibrated before applying this feature.

•

Offset enabled

: Check this box to enable the user measurement offset option. If checked enter an

offset value or a target value:

•

Offset value

: Enter an offset value to manually adjust (increase or decrease) the current

measurement value. If the gas unit type or gas unit (defined in the main measurement
configuration screen) are changed, the offset value is automatically reset to zero.

•

Measurement

: This field cannot be updated. It shows the current measurement value with the

offset value applied.

•

Target value

: Enter a target measurement value. The offset value is then automatically

computed so that the displayed measurement value will be equal to the target value.

•

Compute offset

: Use this button to recompute the offset value at any time during the

measurement process. The offset value will be computed based on the current and target
measurement values.

•

Out of range protection

: Enabled by default. When enabled and the measured value exceeds the

instrument specification, the measurement interval will be increased to 1minute to protect the lifetime
of the sensor spot. If disabled, the lifetime of the spot can be negatively impacted if the sensor is
exposed to high oxygen concentrations for long periods of time.

•

Ext. pres. sensor

: Check as appropriate. Refer to

External pressure calibration on page 64

•

Measurement interval

: This parameter defines the interval for refreshing the measurement value on

the display. Set the value to between 2 and 60 seconds, according to your response time
requirements.

•

Hold recovery time

: This parameter defines the interval during which the outputs remain frozen after

the measurement is no longer on HOLD. Set the value to between OFF and 10 minutes, according to
the timing of your setup.