Rae MiniRAE Plus PGM-76, Operation And Maintenance Manual

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SECTION 2 OPERATION OF MINIRAE PLUS
2 - 4
2.2 Two Modes of Operation
The MiniRAE Plus PGM-76 Profession PID unit offers two
different operating modes:
1) Industrial Hygiene Mode ( simplified as Hygiene Mode): In
this mode of operation, the unit measures the air sample once
each second and compares it with a preset peak alarm limit.
These same measurements are also averaged over one minute
intervals with the resulting value used to compute Time
Weighted Average (TWA) and Short Term Exposure Level
(STEL) values, which are themselves compared to preset alarm
limits.
In addition, the STEL values are captured and recorded every
15 minutes for up to 12 hours. A time stamp indicates when the
unit was last turned on and off.
2) Site Survey / Leak Detection Mode (simplified as Survey
Mode): In this mode of operation, the unit measures air sample
once each second and compares it with a preset low alarm limit.
A variable frequency alarm signal is generated in proportion to
the magnitude of the measurement. When datalog is enabled,
the average value or the peak value over a sampling period
which can be programmed from 1 second to 9999 seconds
(166 hours) is stored.
The datalogging can be initiated manually (event driven ) or the
unit can perform continuous sampling (automatic ). Up to 50