ANATEL A643, Operator'S Manual, Page: 106 / 222

106 of 220 Anatel A643a Alarms - Anatel A643a
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Operator Manual
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In the example, the LED indicating the instrument on Channel #4 has changed from green to
flashing red, indicating a TOC excursion. The user can acknowledge the alarm and display its
summary status by pressing the AKey.
The Controller LCD also is used to display Analyzer malfunctions, reported as Codes
(see
“Alarm Codes” on page 175 ). Different than a limit excursion, a Code indicates an
electromechanical or analytical failure. The Analyzer’s Channel LED and the Controller’s
display still flash, but there is no audible alarm (regardless of the
Beeper Setup ) to alert the
user that there is a problem.
7.3.1 Uncompensated Conductivity Alarms
Alarms are reported for conductivity excursions only in the Uncompensated Mode (see “Sensor
Diagnostics” on page 182 ) and require that Conductivity and Uncompensated be selected in
the Display Units Menu .
The actual (uncompensated) conductivity limits are in accordance with the specifications set
forth in the method “<645> Water Conductivity” of the USP 25–NF 20 (January, 2002). These
temperature-based limits are:
The actual sample water temperature is rounded downward to the nearest 5° increment in
order to establish the conductivity limit, thereby assuring any potential excursions are detected
early. For example, if the measured water temperature is 24.5 °C, the 20 °C limit is applied and
an alarm is generated if the conductivity exceeds 1.1 µS/cm.
To ensure agreement between all data outputs on the System, TOC, conductivity and
temperature values are all rounded to match the Controller’s accuracy for alarm limit checking,
display, printouts, and any digital outputs.
Table 7-1 :
Temperature-based Conductivity Limits
Temperature
(°C)
Conductivity
(µS/cm)
Temperature
(°C)
Conductivity
(µS/cm)
0 0.6 55 2.1
5 0.8 60 2.2
10 0.9 65 2.4
15 1.0 70 2.5
20 1.1 75 2.7
25 1.3 80 2.7
30 1.4 85 2.7
35 1.5 90 2.7
40 1.7 95 2.9
45 1.8 100 3.1
50 1.9