PT1E-0930
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10.DEFINITION OF WORD
LEL
The abbreviation LEL stands for Lower Explosive Limit of flammable/combustible
gases and vapors.
Lower explosive limit
This represents the lowest concentration which can be ignited by source of ignition,
hence the lowest concentration which can produce and explosion.
Calibration
By using calibration (standard) gas etc, it seeks for instrument reading, display value or set
value and true value.
Maintenance mode
When make maintenance of this unit, shut off the alarm and the output of signal showing the
maintenance mode condition is displayed on the external output signal.
By this, the maintenance is carried out independently on this unit.
Press MODE switch for 3 seconds, and the maintenance mode starts.
Initial clear
The reading will be unstable for a few seconds after power on. In this moment to prevent
the error of running, the alarm contact shall be cut off. Then, signal output showing initial
clear condition is given on external output.
Alarm delay time
To prevent the alarm error by noise intruded from the outside, this is the function to suspend
the running temporarily.
Alarm response time
The time to get an alarm when exposed to gas concentration of 1.6times alarm level.