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MODEL CLARITY II
SECTION 8.0
TROUBLESHOOTING
SECTION 8.0
TROUBLESHOOTING
8.1 OVERVIEW
The Solu Comp II analyzer used in the Clarity II turbidimeter continuously monitors itself and the sensor for prob-
lems. When the analyzer detects a problem, the word fault or warning followed by
s
s
appears in the display alter-
nately with the measurement. If alarm 3 was configured as a fault alarm and a fault has occurred, the relay will
energize. The outputs do not change during a fault or warning condition. They continue to reflect the measured
turbidity or TSS value.
To read fault and warning messages, go to the main display and press
s
s
. The analyzer will
automatically scroll through the messages and will continue to scroll through the mes-
sages for two minutes. After two minutes the display will return to the default screen.
To stop the automatic scrolling and return to the main display, press MENU then EXIT.
Error messages are prefaced by the word fault or warning.
Faults are conditions requiring immediate attention from the user. Measurements made by the analyzer should
be regarded as being in error.
Warnings are less serious than faults. A warning signifies the existence of a condition requiring attention. The
instrument remains usable.
8.2 TROUBLESHOOTING USING FAULT CODES
SN identifies the sensor affected. S1 is sensor 1; S2 is sensor 2.
8.2.1 Lamp/LED Failure
The light source in a Clarity II turbidity sensor can be either a tungsten filament lamp or an LED. USEPA-compli-
ant sensors use a tungsten lamp. ISO-compliant sensors use an LED. A photodiode inside the sensor continuously
monitors the intensity of the light source. The source intensity measurement is used to correct for source drift,
which allows the sensor to operate for longer periods without calibration. If the signal from the photodiode drops
below a certain value, the analyzer assumes the light source has either failed completely or the intensity is too low
to be useful. At this point the analyzer displays the
Lamp Failure
message.
Replace the lamp or LED board. See Section 7.2.2.
After replacing the lamp board, be sure to recalibrate the sensor using either slope or standard calibration. See
Section 6.2 or 6.3. Recalibration is necessary to reset the lamp power supply. Grab calibration will not reset the
power supply and may result in significantly reduced lamp life.
Fault message
Explanation
Section
SN Lamp/LED Failure
Lamp or LED is burned out
8.2.1
SN Sensor Fail
Photodiode circuit measuring scattered light has failed
8.2.2
EEPROM Failure
Cannot save data to non-volatile memory
8.2.3
Factory Failure
Needs factory calibration
8.2.4
Warning message
Explanation
Section
SN Need Cal
Lamp intensity is weak but can be improved by
8.2.5
calibrating
SN Weak Lamp
Weak lamp, replace as soon as possible
8.2.6
WARNING!
Explosion hazard. Do not disconnect equipment when a flammable or
combustible atmosphere is present.