InPro 6850 i / 6900 i / 6950 i O
5
Operation
a
Important! Before using the sensors for the first
time, the electrolyte must be filled in (see "Chap-
ter 6.2").
5.1
Start-up and polarizing
a
Important! The protection cap must be removed
before mounting the sensor in the process.
When the system is operated for the first time or if
the sensor has been disconnected from the voltage
source (transmitter or O
than 5 min u tes, the sensor has to be polarized prior
to calibration by connecting it to the operating O
transmitter or to a sensor master. After 6 hours, the
sensor is fully polarized and ready for operation.
h
Attention: The InPro 6950 i should never be polar-
ized at air!
During this time, it is recommended to keep the pro-
tection cap filled with fresh conditioning solution on
the sensor (see "Section 7 – Storage"), especially if
the sensor is being polarized for longer than 6 hours.
A shorter polarization period is sufficient if the sensor
has been disconnected for only a few minutes. The
following table serves to establish the correct polar-
ization time in relation to the depolarization time.
Depolarization time
t
depol
30 > t
15 > t
1 Depolarization time: Time span in which the po-
larization voltage is cut off from the sensor. This
is the case:
– during the time the cable is disconnected or no
– after changing the electrolyte or membrane
2 Polarization time: Time span during which the
sensor is under a polarization voltage.
a
Important! Setting of the polarization voltage on
the transmitter for correct measurements:
– Standard applications InPro 6850 i: – 675 mV
© 04 / 13 Mettler-Toledo AG
Printed in Switzerland
[Min.]
t
> 30
depol
> 15
depol
> 5
depol
t
< 5
depol
t ransmitter or sensor master is connected to
the cable, or the transmitter has been discon-
nected from the current supply.
body. In this case at least 6 hrs of polarization
must follow.
Sensor 12 / 25 mm
2
sensor master) for longer
2
Minimum required
1
polarization time
360
6 3 t
depol
4 3 t
depol
2 3 t
depol
InPro 6850 i / 6900 i / 6950 i
17
2
[Min.]
2
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