RKI Instruments RX-517 - Manual (Page 32)

PT0E-0730
31
９．Definition of words
Vol%
Gas density is expressed by the unit of a part.
ppm
Gas density is expressed by the unit of a part per.
10,000ppm＝1vol%
%LEL
Suppose to put the Lower Explosive Limit as 100 and at that time, combustible gas density
is expressed by the unit of a part per hundred.
Iso-butane：100%LEL＝1.8vol%
N-hexane ：100%LEL＝1.2vol%
Calibration
By use of calibration gas etc, it is to adjust the reading, display value or set value to
the true valued.
PEAK value
MAX or MIN value in a period.
ALARM preset value
This is an alarm preset point value to give alarm when it comes to this alarm point.
Maintenance check
This is a work to maintain the required function and condition to perform.
Data logging
Every internal of period, the function to save memory of gas density at alarm is provided.
Hung-up phenomenon
After suck the high density gas and introduce fresh air into instrument, the phenomenon to
show higher reading by effect of residual gas for a while.
Oxygen deficiency
According to the decrease of oxygen, it is a phenomenon to make trouble for humans.