30
MW150 & MW151 Bench Meters
9. ORP
9.1. PREPARATION
To perform ORP measurements, connect an ORP electrode (see “Accessories” section for
code) to the instrument and turn it ON.
9.2. ORP CALIBRATION
The ORP range is factory calibrated and cannot be calibrated by the user.
MA9020
ORP
Solution can be used to confirm that the ORP sensor measures correctly. mV readings are
not temperature compensated.
9.3. ORP MEASUREMENT
MW150
and
MW151
are factory calibrated.
If necessary, enter the mV mode by pressing the RANGE/
until the display changes to mV.
Immerse the ORP electrode tip app. 4 cm (/1½”) into the sample and wait until the stability
indicator (hourglass icon) disappears.
The bench meter will show the ORP (mV) value on the primary LCD together with
temperature of the sample on the secondary LCD.
pH
mV
NO MTC
ATC
USB
OPEN
AUTO
HOLD
SLOPE
CLEAR
CAL
1.68
4.01
6.86
7.01
9.18
10.01
12.45
CUST1
CUST2
DATE
ACCEPT
ºC
ºF
pH
mV
TIME
For accurate ORP measurements, the surface of the electrode must be clean and smooth.
Pretreatment solutions are available to condition the electrode and improve its response
time (see “Accessories” section).
Notes:
When the reading is out of range, the display will flash the closest full-scale
value. If using pH electrode while in mV mode, the instrument will measure the mV
generated by the pH electrode.
