13
7.
mV Standardization (Offset Adjustment)
Oxidization Reduction Potential (ORP or Redox) as measured by an ORP
electrode in milliVolt (mV) units is not a precise measurement, but is useful as a
relative indicator. As such, mV offset adjustment is not meant to enhance
accuracy, but rather to make readings comparable to a reference.
Commercial ORP solutions are commonly used as a check standard – a
meter/electrode system is verified to be close to a given value although
adjustments are not made. These solutions can be used as a calibration standard
in which adjustments are made in an attempt to match the ORP value, however
results are often difficult to reproduce.
1)
Turn meter on, connect a combination ORP electrode (such as 13-620-81),
and press MODE if needed for mV (or R.mV) measurement.
2)
Dip the ORP electrode into a solution with a known mV value (i.e. Zobel,
Light’s, quinhydrone, or iodidetriiodide) with brief or slow stirring.
3)
Press STD to begin standardization.
4)
Adjust the value using
▲
/
▼
keys, press STD when the reading is stable to
accept the calibration offset. The maximum adjustable value is ±150 mV from
the factory default mV value.
5)
To view the Ion Standardization Report at any time from the measure screen,
press
REPORT
.
8.
Temperature Setup
Use Setup Temperature mode to desired temperature units; ºC or ºF.
Press
SETUP
from the measurement screen and then press
ENTER
when
TEMPERATURE
is selected.
Choose ºC or ºF units of measure.
Automatic Temperature Compensation (ATC) is automatically applied when a
temperature sensor is connected.
Manual Temperature Compensation (MTC) of 25 ºC is used if the temperature
sensor is not connected. See
Section 9 – Temperature Standardization
to adjust
the MTC temperature value.
When an offset has been stored successfully, R.mV replaces
mV in measurement mode.
