In-Situ TROLL 9500 Operators Manual - Manual (Page 74)

67
TROLL 9500 Operator’s Manual 0095110 rev. 007 01/09
sensor
removal
tool
E
o
is related to the potential of the reference electrode,
R is the Gas Law constant,
F is Faraday’s constant,
T is the temperature in Kelvin,
n is the ionic charge (+1 for Hydrogen), and
[H + ] is the hydrogen ion concentration in moles/L.
The MP TROLL 9500 reads the signal from the pH electrode, the
reference electrode, and the temperature and then calculates the pH
using the Nernst equation.
SENSOR INSTALLATION
The MP TROLL 9500 may be shipped with a pH or combination pH/
ORP sensor installed. If installation is necessary, unpack and install
the sensor in the MP TROLL 9500 as follows.
A combination pH/ORP sensor will work properly only in
port 1. A pH sensor may be installed in port 1 or 3.
TIP: To ensure optimum response for a new or previously
stored sensor, rinse off the soaking solution, then soak the
sensor in clean water for at least 15 minutes before calibrating.
1. Remove the restrictor or Cal Cup from the front end of the MP
TROLL 9500. This allows access to the sensor block shown below.
2. Remove the sensor hydration bottle and set aside for future use.
3. Rinse the sensor in clean water to remove the soaking solution.
Soak the sensor in clean water for at least 15 minutes before
calibrating.
4. Remove any moisture or dirt from the area around
the port where you will install the sensor, then use the
sensor removal tool to remove the plug from the port.
Retain the plug for future use.
5. Remove any moisture or dirt from the port connector
with a clean swab or tissue.
6. Remove the cap from the sensor connector. Check lubrication of
the o-rings. If they appear dry, apply a silicone lubricant before
installation.
7. Visually align the sensor connector pins with the port connector pins.
8. Press the sensor into the port until you feel it dock with the port con-
nector. When properly inserted a small gap (the width of the sensor
removal tool) remains between the instrument body and the widest
part of the sensor, for ease of removal.
CALIBRATION
OVERVIEW
Several options are available for pH calibration.
s
D.O., conductivity) at the same time with one convenient solution. A
one-point calibration in pH 7; default slope, calculated offset.
s
in calculation of sensor offset for a single pH value (pH 4, 7, or
10). Select a calibration solution for the region of the pH range you
expect to measure. A one-point calibration may be used with good
results when the sensor is new.
s
calculation of sensor slope and offset for one pH range (pH 4-7 or
pH 7-10). Choose solutions that bracket the expected pH range:
SECTION 11: PH
Pressure/Turbidity
(or plug)
Temperature
Install a pH/ORP
sensor in port 1
alignment mark
pH/ORP Sensor Position
Pressure/Turbidity
(or plug)
Temperature
Install a pH sensor in
port 1 or port 3
alignment mark
pH Sensor Positions