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<6. Converter Operating Functions>
6-1
IM 12F4A1-01E
6. Converter Operating Functions
Operating functions related to converter operation were partially described in 5. Converter
Operation.
This chapter describes details of the already described functions and the other operating
functions.
6.1 <failure> Detecting Operation
For types of <failure> detected, see subsection 5.3.3 (8) and others. This section describes
detecting operations for major <failure>.
The <failure> status is reset by turning the power off. If abnormal cause is not eliminated after
turning the power on, <failure> is detected again and <FAIL> lamp turns on.
6.1.1 Concentration Range Exceeded (Err11)
This is an error which occurs when sample water residual chlorine concentration has exceeded
the range of -0.5 to 11.0 mg/l or the current input has exceeded the predetermined range owing
to a failure in the measuring circuit system or the like.
Current input check is conducted based on either “Low” or “High” range and it is defines that error
occurs when either the range of -7.5 to 37.5 µA or -20 to 70 µA respectively.
Whether “Low” or “High” range is selected is automatically determined by whichever is the large
value (mg/l) of two upper limit values in “output range-1” and “output range-2”. If the larger upper
limit value is 5.00 mg/l or less, the current input range “Low” is selected, while if it is more than
5.00 mg/l, “High” is selected.
When plateau characteristics are taken, the current input value may exceed the permissible
range depending on the applied voltage to be set.
Thus, when plateau characteristics are taken, error code “Err11” failure detecting function is
temporarily stopped so that no <failure> is detected.
6.1.2 Sample Temperature Failure (Err12, Err24)
When the sample water temperature exceeds the temperature compensation range (0 to 40
°C) or the temperature input signal value exceeds the permissible range corresponding to that
temperature owing to electric circuit system failure, <failure> of error code “Err24” is displayed.
Also, the sample water temperature exceeds the measuring range ( 0 to 50 °C), <failure> of error
code “Err12” is displayed similarly.
The detecting function for “Err24” (temperature compensation range exceeded), “execution/stop”
can be selected using function code “4.” in <PROGRAM.2> mode (see subsection 5.3.5).
6.1.3 Out-of-Sample in the Measuring Tank (Err13)
In <MEAS.> mode, when the circuit between electrodes is open owing to decrease of sample
level in the measuring tank, <failure> of error code “Err13” (out-of-sample in the measuring tank)
is displayed.
However, this detecting function does not operate for about two minutes after power is turned
ON. This function also does not operate when “oFF (stop)” is selected using function code “b.” in
<PROGRAM.1> mode.
The detection principle of “Err13” uses the fact that residual chlorine concentration indication
reads approx. 0 mg/l without sample water in the measuring tank. However, since out-of-sample
must be identified from the state when residual chlorine concentration in the measuring tank
is close to 0 mg/l, the diffusion current change is also confirmed when the applied voltage is
changed.
14th Edition : Jul. 15, 2020