8.7Auto calibration
In this analyzer, the signals form the input/output terminals on the upper can be used for driving an external solenoid valve and introducing standard gas, whereby zero point and span can be calibrated automatically. The auto calibration is done according to 8.7.1 Current time setting, 8.7.2 Auto calibration start time setting, 8.7.3 Auto calibration cycle setting, 8.7.4 Auto calibration ON/OFF setting and 8.7.5 Output Hold setting at Calibration.
Cautions on operation
1.When the auto calibration start time is reached during key operation, the auto calibration is given priority and is started. All key operation will be invalid until the auto calibration is finished.
2.To forcibly interrupt the auto calibration in progress, press both the ENT and CAL keys simulta- neously. After the forcible interrupt, the measuring mode is resumed and all the keys are operable. Although the current auto calibration will be passed over, it will be started from the initially set cycle from the next time onward.
Example: When auto calibration is set for 3 hour intervals starting from 8:00 a.m.
: Under auto calibration
8 : 00 | 11 : 00 | 14 : 00 | 17 : 00 |
8 : 00 | 11 : 00 | 14 : 00 | 17 : 00 |
|
| Forcible interruption |
|
3.Key operation is possible while calibration is not under way with the auto calibration function set. Therefore all settings (of span, hold, remote range, time, etc.) including manual calibration can be made. But note that if the wrong time is set on the clock, the auto calibration will not be started at the correct time.
4.Auto calibration is able to start by applying remote start input signal, 5V DC longer than 100msec, to remote start input terminals. In this case, auto calibration will start independent to its ON/OFF setting. (Calibration starts at the trailing edged of signal.)
5.When measuring 4 components, or NOx, SO2, CO and O2 (with 2 infrared gas analyzers), the auto- matic calibration cycle should be set on the CO/O2 analyzer side and the automatic calibration of NOx/SO2 analyzer should be turned OFF. After the automatic calibration of CO/O2 analyzer, the automatic calibration of NOx/SO2 analyzer will be started.
– 18 –