YOKOGAWA RC400G, User Manual

Page: 75 / 141

<5. Converter Operation>
5-22
IM 12F4A1-01E 14th Edition : Jul. 15, 2020
Function code “1” sets the range of “output range-1” and function code “2” sets the range of
“output range-2”.
In the following, key operations for range setting are shown. The key operation procedure is the
same both in output range-1 and output range-2.
(Example)
(a) Select function code "1" (or "2"). → L00.00 mg/l
(Lower limit value display)
(b) On pressing [>] key, the lower limit value can be entered. → L 00.00 mg/l
(If change is not required, start operation at step (d).)
(Leftmost numeral flashes.)
(c) Select a digit using [>] key, set a numeric value limit value
using [Λ] and [>] keys. → L0 1.00 mg/l
(Last setting digit flashes.)
(d) On pressing [ENT] key, the upper range value is displayed. → H05.00 mg/l
(If change is not required, start operation at step (f)).
(e) Change the numeric value in the same operation as
shown in step (b) and (c). → H0 3.00 mg/l
(f) On pressing [ENT] key, setting is performed. → H03.00 mg/l
(The display once flashes.)
(On repressing [ENT] key, the step is returned to (a). Confirm the set value.)
If both the upper and lower limit values are not to be changes, only confirmation operation of the
set values is performed. Thus, when operation of step (f) is executed, the display does not flash.
The permissible setting range is 0.00 to 10.00 mg/l for both the upper and lower limit values.
However, span (= “upper limit value” - “lower limit value”) must be 1.00 mg/l or more.
If a setting that does not meet the conditions is performed, “not” is displayed. Reset this display
using [>] key and set again.
Permissible span range is checked when the upper limit value is set (operation procedure step
(f)).
Table 5.17 shows the initial values of “output range-1” and “output range-2”.
Table 5.17 Initial Values of Output Ranges -1 and -2
Output Range Lower Limit Initial Value Upper Limit Initial Value
1 0.00 mg/l 5.00 mg/l
2 0.00 mg/l 10.00 mg/l
(2) Reference Sensitivity Setting (Function code “4”)
NOTE
Products which can be set using this function code are those of “version 1.02” or later. In products
earlier than version 1.02, use the function code “7.” in service mode.
The reference sensitivity set on shipment is the value of “2.62 µA/(mg/l) at 20 °C” based on
amperometric titration.
In span calibration, if standard solution residual chlorine concentration measured by manual
analytical methods other than amperometric titration (such as chlorimetry and iodometric
titration) is entered, great variance may occur between the sensitivity calculated from this value
(measured sensitivity) and the set reference sensitivity. In particular, this trend is stronger when
residual chlorine concentration is low or a sample water is used as the standard solution.
The RC400G residual chlorine analyzer detects an error (“Err22”) when the measured sensitivity
is less than 50 % of the reference sensitivity and makes that span calibration invalid.