YOKOGAWA Vigilant Plant EXA TB Series, User Manual

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<6. PROCEDURES FOR CONVERTER OPERATION>
6-11
IM 12E04A02-02E
3. Wait one minute or more and after the display => 000.00 mg/l is displayed.
becomes stable, and press the [>] key.
4. Press the [ENT] key to calibrate. => 000.00 mg/l
The entire display fl ashes once and
then the CAL lamp goes out.
In addition, at operation 4, the zero-calibration range is checked and the permissible range (-10
to 10 mV) is exceeded, Err21 (zero-calibration overrange) is displayed (see Section 5.3 *3). In
this case, the "FAIL" lamp is not lit and a FAIL contact is not output.
The error message can be reset by pressing the [ENT] key and the display returns to the turbidity
indication. Wait until the display becomes stable and then begin from step 2 again.
In any stage of zero-calibration operation, pressing the [MODE] key or [FUNC] key allows
switching to another mode or function. Calibration computation is not performed unless
operation of 4 is carried out. Also, since the lamp voltage returns to the control voltage when
the turbidimeter resets from the function for calibration with the lamp turned off, a little time is
necessary until the turbidity reading becomes stable. When the mode is to be changed to the
<MEAS.> mode, change the mode after waiting for fi ve minutes or more.
Note: At this calibration, the turbidity not multiplied by the correction factor from the zero-shift
calibration (zero correction) in (3) or span calibration (sensitivity correction) in (5) is displayed.
(3) Zero-shift Calibration (FUNCTION "3")
At any turbidity value, this is an operation to zero-shift a turbidity reading within the permissible
range (±9 mg/l).
For details on the function, see Section 5.3 (*3). The zero-correction factor obtained in this
calibration can be displayed and directly changed in FUNCTION "B" in the <PROGRAM1>
mode.
The operation procedures are as follows.
(Example of display)
1. Select FUNCTION "3" in the <MAINT.> mode. => 000.13 mg/l
2. Wait until the display becomes stable, and => 000.13 mg/l
then press the [ENT] key. The CAL lamp fl ashes.
3. Press the [>] key. => 00000. mg/l
The display is now ready for
determination of the decimal point
position.
4. Press the [>] key to determine the position => 000.00 mg/l
of decimal point.
Every time the key is pressed, the decimal
point moves to the right and when the least
signi fi cant digit is reached, the decimal point
then moves to the second digit from the left.
5. Press the [ENT] key. => 000.00 mg/l
The second digit from the left fl ashes
and waits for the turbidity setting.
6. Select a digit with the [>] key and set the => 000.22 mg/l
turbidity value using the [^] or [v] key.
Every time [>] key is pressed, the fl ashing digit
moves to the right and when the least
signi fi cant digit is reached, it moves to the
second digit from the left.
7. Press the [ENT] key to terminate calibration. => 000.22 mg/l
The entire display fl ashes once and
the CAL lamp goes out.
3rd Edition : May. 31, 2010-00