The Armstrong Monitoring Corporation AMC-400 Series, Руководство пользователя

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AMC-400 Series Digital Transmitter with Smart Sensor 2
3
1.6 GLOSSARY
Alarm Alarm is an audible, visual, or physical
presentation designed to warn the instrument user
that a specific level of a dangerous gas/vapor
concentration has been reached or exceeded.
Calibration Calibration is the procedure used to adjust the
instrument for proper response.
Calibration Gas Calibration Gas is a gas of known
concentration(s) used to set the instrument span.
Catalytic needs air for calibration.
DT Digital Transmitter
Gas Concentration Gas Concentration is measured in:

PPM

%LEL (Lower Explosive Limit)
LEL
Lower explosive limit is the lowest concentration
(percentage) of a gas or a vapor in air capable of
combusting in the presence of an ignition source
(arc, flame, heat).
PPM Parts Per Million (1% volume = 10,000PPM)
Percent by volume Concentration of gas in a mixture expressed as a
percentage of total volume.
RS-485 Superseded with EIA-485 or TIA-485. This
standard defines the electrical characteristics of
drivers and receivers for use in balanced digital
multipoint systems.
Span Full range of a sensor i.e. a CO sensor with a full
range of 0-100 PPM has a 100 PPM span.
T90 Response Time in seconds to achieve 90% gas
concentration reading. This a typical calibration
point that allows for sensor aging, but tends to be
less accurate than a T99 calibration,
T99 Response Time in seconds to achieve 99% gas
concentration reading. This is a more accurate
calibration point.
Zero Buffering Zero buffering is transmitter function which
forces the gas concentration reading to zero when
sensor is exposed to low concentration of a gas.
The zero buffer is indicated in the sensor
specification.
Zero Gas Zero gas is gas in which the target gas is not
present. The presence of oxygen is required.
Clean air is an excellent source for zero
calibration. A known gas concentration can be
entered during zero calibration.