Endress+Hauser OxyMax W COS 31, Operating Instructions Manual

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8 Trouble-shooting OxyMax W COS 41
24 Hauser
8.2 Sensor test
"
Caution!
Only authorised and trained personnel may test the sensor.
You will also require a multimeter (voltage, resistance).
Then carry out the following to test the sensor:
!
Note!
If there are deviations from the reference values, follow the troubleshooting instructions
or contact your E+H sales office.
8.3 Spare parts
•
Replacement cartridge COY 31-WP for replacing membrane cap
2 preterminated spare replacement cartridges with pretensioned membrane;
Order No. 51506976
•
Sealing ring COY 31-OR
3 pieces; Order No. 51506985
Test Measure Setpoint
Voltage inspection With the sensor connected,
test the polarisation voltage on the
Liquisys M COM 223/253-DX/DS
transmitter between terminals 90 and 91:
– 650 mV
Slope inspection Place the sensor in the air, and dry with
a paper towel After 10 minutes, the measured value
display should display approx. 102%
SAT (display by 4 times »+« -key).
Zero point inspection Immerse the sensor in zero solution
(see "Accessories" page 22).
Wait for 15 minutes (consumption of
the residue of oxygen in the sensor).
Open the measuring chamber and dry
the electrodes
Display near to 0 mg/l (0% Sat)
Display near to 0 mg/l (0% Sat)
Temperature sensor
check Disconnect the sensor and measure
the resistance between red and brown
flexible wires depending on temper-
ature:
5°C
10°C
15°C
20°C
25°C
30°C 74.4 k
Ω
58.7 k
Ω
46.7 k
Ω
37.3 k
Ω
30.0 k
Ω
24.3 k
Ω
Cable check Disconnect, open and dry the sensor.
Measure the resistance between Gold
cathode and white braided wire.
Measure the resistance between anode
and green braided wire.
< 1
Ω
< 1
Ω