YOKOGAWA EXA TB TB400G, User Manual

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<4. OPERATION>
4-7
IM 12E04A02-02E 9th Edition : Mar. 16, 2018-00
b. With Automatic Zero Calibration (Suffix code: -A3)
Automatic cleaning can be start in the following two ways.
• Startup with the internal timer.
• Startup with FUNCTION “6” in the <MAINT.> mode (see Section 6.5).
Note: Startup with the internal timer can be selected for execution (on)/stop (off) using FUNCTION “A” in the <PROGRAM1> mode. It
has been to execution (on) when shipped from the factory.
The internal timer operation is shown in Figure 4.7.
As shown in the figure, the automatic cleaning operation is repeated at every set time of the
cleaning period (A) and automatic zero calibration is implemented once in every 3 repetitions (for
cleaning calibration ratio B = 3).
A A A A A
A
Measurement start *1
F0407.ai
B=1 2 3 1 2 3
Cleaning Cleaning Calibrattion Cleaning Cleaning Calibrattion
*1: Measurement start is defined to be the point specified in the following:
Other mode <MEAS.> mode
Power off Power on (<MEAS.> mode)
Figure 4.7 Cleaning (calibration) period (Example: for cleaning calibration ratio = 3)
However, if startup of the automatic zero calibration with the internal timer is stopped, the
cleaning operation becomes the same as in Figure 4.5 because the automatic zero calibration
operation is eliminated.
Figure 4.8 shows the automatic-cleaning operation time chart and Table 4.3 the settings.
<Valve used>
SV1: Drain valve
SV2: Cleaning-water valve
SV3: Measuring-water valve
SV4: “Zero-water” valve