Testing The Sensor Via A Transmitter - Mettler Toledo InPro 6800 Serie Bedienungsanleitung

InPro 6800 O
If the LED does not light up, you should check the
battery of the O
manual «Accessories» ). If the battery is working,
than there is probably a problem with your sensor.
You should change the electrolyte and/or the mem-
brane body of your sensor. If after a membrane
change the LED still does not light up, this means
that there is maybe something wrong with the inte-
rior body of the sensor. You should than change it
(see «Section 6.2»).
h
Important! The Sensor Check function only veri-
fies the correctness of the electrode current for air
measurement. In order to be absolutely sure of the
functionality of the sensor, the residual signal in an
oxygen free medium should also be controlled (see
«Section 6.1.3»).

6.1.3 Testing the sensor via a transmitter

A periodic zero current measurement (no zero point
calibration) is recommended for verification of proper
sensor function.
h
Note: At the time you carry out the zero current mea-
surement, the sensor must be polarized.
Zero current measurement can be done by using zero-
ing gel (order no. 30 300 435) or nitrogen (N
carbon dioxide (CO
of at least 99.995 %, alternatively in a sample medium
saturated with one of these gases.
After 2 minutes in an oxygen-free sample medium, the
reading on the transmitter should drop to below 10 %
of the reading in ambient air, and within 10 minutes the
value should have dropped to below 1 %.
If the measured values are too high, this suggests a
depleted electrolyte or a defective membrane. In the
first instance replace the electrolyte, and in the second
case exchange both the membrane body and the elec-
trolyte accordingly.
If after such procedures the above mentioned values
are still not reached, replace the interior body. If this
doesn't solve the problem too send the sensor to your
local METTLER TOLEDO representative for inspection.
Many sample media contain volatile substances which,
even at very low concentrations, have a clearly percep-
tible smell. Similarly to oxygen, these sub-stances are
able to invade the electrolyte through the gas-permeable
membrane. Accordingly, they become noticeable when
changing the electrolyte. In most cases, such sub-
stances have absolutely no influence on the measuring
properties of the sensor. Slight discoloration of the elec-
trolyte also has no effect on the measuring properties.
© 02 / 2023 METTLER TOLEDO
Printed in Switzerland
Sensor 12/25 mm
2
Sensor-Master (see instruction
2
) calibration gases with a purity
2
27
) or
2
InPro 6800
52 200 953 C