Teledyne LXT-280 - Manual (Page 49)

Dissolved Oxygen Transmitter Maintenance
Teledyne Analytical Instruments 39
Broken membrane
Replace the electrode
cartridge.
Process flow is not
adequate across the
electrode membrane
Locate the sensor within an
adequate flow or create
agitation within the
process.
Sensor is located too close
to the oxygen injection
point. Locate the sensor further
from the oxygen injection
point.
Signal conditioner not
properly engaged in the
rear of the sensor body.
Verify that the signal
generator is properly
engaged in the rear of the
sensor body.
Instrument has been
improperly calibrated. May
have been calibrated with
no slope (infinite gain) Verify instrument
calibration electronically,
then recalibrate per
Section 4.
Membrane is coated
Clean the membrane. See
Sensor manual.
Slow Response
Protective Boot was left on
the front of the sensor. Carefully remove the
protective boot.
Broken membrane
Replace electrode
cartridge.
No Span
Temperature compensator
(TC) is open.
Verify that the sensor is
properly connected
including the TC
connections. Check for a
damaged TC in the sensor
body. Replace if damaged.
Reading drifts upscale or
zero calibration reads
upscale
Broken membrane
Replace the electrode
cartridge.
Broken membrane
Replace the electrode
cartridge.
Coated membrane
Clean the membrane. See
Sensor manual. Verify
instrument calibration.
Short span or the electrode
does not respond to a
second calibration point.
Electrode cartridge is not
fully engaged in the sensor
body Check electrode cartridge
to see that it is fully
engaged in sensor body