Thermo Scientific 5028i, Инструкция по эксплуатации

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Thermo Fisher Scientific Model 5028
i
Instruction Manual 4-1
Chapter 4
Calibration
The Model 5028 i is an instrument that can make accurate mass
concentration measurements of PM
10
, PM
2.5
and PM
1.0
. However, with
all electronic instruments, the accuracy of the measurements depends
on proper calibration.
In general terms, calibration, also called standardization, is the process
that establishes the relationship between sensor output signals and
the parameter the operator is attempting to measure. The 5028 i
instrument uses sensors that measure temperature, humidity, pressure,
and radiation. This chapter describes the procedures for performing
the necessary sensor calibrations. This chapter is also a follow-up to
the Acceptance Testing outlined in the “ Installation ” chapter and a
continuation of the menu display descriptions in the “ Operation ”
chapter.
Each instrument is calibrated and tested for accuracy at the factory.
The mass calibration is conducted with a set of NIST-traceable mass
calibration foils. The radiation detector is calibrated against certified
check sources for beta and alpha emissions. The temperature, relative
humidity, pressure and flow rate are all calibrated against NIST traceable
standards.
It is recommended that the instrument be calibrated once per year and
encounter quality checks on a periodic basis in accordance with the
users specific quality assurance project plan. For example, volumetric
flow checks on a two-week basis are common in some air monitoring
agencies and with full-scale quarterly audits for flow and mass. The
Quality Assurance Handbook for Air Pollution Measurement Systems ,
published by the U.S. EPA, Research Triangle Park, NC 27711, can be
consulted for detailed quality assurance guidelines.
Optional mass transfer standards are available from Thermo Fisher
Scientific for performing an annual mass calibration. However,
additional specialized equipment is needed to calibrate the Model 5028 i
for temperature, relative humidity, barometric pressure, and volumetric
flow. The following equipment should be used:
l
A thermistor or thermocouple thermometer capable of measuring
ambient temperatures in a range of –20 to 50 °C, readable to the
Frequency of
Calibration
Equipment Required