ATA Pro
Technical Manual
Int. Approved
Document ref: HEL-810-12
December 2017
Page 12 of 27
Copyright © 2017 Analox Ltd. All Rights Reserved.
Commercial in Confidence
5.2
Sensor Replacement
O
2
sensor
a) Replacement sensor part number: 9100-9212-94.
b) In a clean, dry environment, open the analyser case.
c) Disconnect the O
2
sensor from the circuit board.
d) Unscrew the O
2
sensor locking ring on the front face of the analyser.
e) Pull out the O
2
sensor.
f) Dispose of the old sensor according to local regulations for Lead and
Potassium Hydroxide solution.
g) Remove the new sensor from its pack and check it for leaks, check the
sensor has a rubber o-ring fitted at the base of the thread on the front of
the sensor. Push the sensor through the hole in the lid and screw on the
locking ring.
h) Connect to the circuit board.
i) Close the lid.
He Sensor
a) Replacement sensor part number: 9100-4535
b) In a clean, dry environment, open the analyser case.
c) Disconnect the He sensor from the circuit board.
d) Unscrew the He sensor locking ring on the front face of the analyser.
e) Pull out the He sensor, and dispose of it.
f) Remove the new sensor from its pack, check the sensor has a rubber o-
ring fitted at the base of the thread on the front of the sensor. Push the
sensor through the hole in the lid and screw on the locking ring.
g) Connect sensor to the circuit board and carry out He coarse calibration.
He coarse calibration
a) Turn the
Ax
ATA pro
on and calibrate the O2 sensor in clean air, as per
the instructions in section 3.2
b) Change the display to show the Helium concentration, and expose the He
sensor to clean air.
c) Adjust the external zero adjust pot to the mid-point.
d) Adjust the internal zero potentiometer until the
display reads 0.0.
e) Expose the sensor to span gas i.e. 100% Helium and allow the reading to
stabilise.
f) Adjust the internal Span potentiometer until the display reads 100, or the
concentration of Helium in the span gas.
g) Close the lid.
