Yokogawa GD40 Gas Density Detector - Manual (Page 164)

<9. CALORIE / CALIBRATION PROCEDURE>
9-5
IM 11T3E1-01E
9.3 Calibration
9.3.1 Semi-automatic Calibration
In this mode of calibration, you can carry out one-touch calibration. To use this feature, you must
observe the following instructions.
• The analyzer needs solenoid valves for controlling the calibration gases (zero and span
gases). Connect the solenoid valves with utmost care to ensure that there is no gas leakage
in the system.
• Install the calibration gas cylinders in a location close to the GD40 detector. If the detector
needs to be installed in an explosion-hazardous area, the solenoid valves being used must
also be protected against explosion.
• The contacts for controlling solenoid valves are built in the GD402T, GD402V, GD402R
converter. It is the user's responsibility to supply power to drive the contacts. You must install
a switch and a fuse along the power line. Note that the contacts are rated at 250 V AC/3 A or
30 V DC/3 A.
[NO] [NO]
XX.XXXX
ZERO
MAN.CAL SEM.CAL
XX.XXXX
SPAN
XX.XXXX
WAIT
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[YES]
* 3
* 5
* 4
START
[YES]
* 2
* 3
* 2
* 5
* 3
[NO]
*2: If a calibration data error [ALM.10] occurs, the display alternates between the [WAIT] and [ALM.10] indications.
The [ALM.10] indication still remains on display even after the mode move to the measurement mode.
This error massage does not disappear until normally ending in re-calibration or resetting the analyzer.
*3: The values are operated and the calibration data are read at the time setpoint (calibration time) which is defined
in the mode for setting automatics/semi-automatic calibration data in CODE 15.
The display always shows the corrected density.
*4: During automatic calibration, the display shows the same data items as those of the [ZERO] and subsequent
indications.
*5: When pressing the [MODE] key during [ZERO] or [SPAN] status, the [WAIT] appears on the display.
When pressing the [MODE] key once again, the analyzer returns to the measurement mode.
(This operation means you have cancelled automatic/semi-automatic calibration.)
Measurement mode
DISP
*1: See" Figure 6.1 Modes of Operation Level" on page 6-8.
* 1
Zero-point density display
Span-point density display
Stabilization time
Figure 9.3 Semi-automatic Calibration Mode