Met One E-BAM, Руководство по эксплуатации

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E-BAM-9805 Manual Rev B.docx Page 51
calibration factors from the RH sensor and to start over with factory default calibration factors. Then
try the calibration again.
Important Note : It is often difficult to calibrate the sensor if the E-BAM is warm, as the heating of
the unit will reduce the sample RH (as it should) making it difficult to compare the E-BAM filter RH
reading to an ambient RH traceable standard reading. If the sensor is to be calibrated, it is best to
do it when the E-BAM is cold (equilibrated to ambient) and the nozzle is raised. It is recommended
to just leave the sensor at the factory default calibration. The E-BAM filter RH sensor is only a ±4%
device when functioning properly and will typically read a completely unreasonable value if it fails,
such as 135% or -25%.
5.10.3 Upper and Lower Pressure Sensors Audit
The upper and lower pressure sensors are used to detect excessive tape loading due to heavy
particulate sampling. If the user defined threshold is exceeded, the sample will be suspended and
the tape advanced to prevent damage to the pump and the tape itself. See section 3.5.6 for details.
To audit these sensors set the Filter Sensor field to the UPPER PRES or LOWER PRES option.
The E-BAM
parameter is the instantaneous output from the unit’s upper or lower pressure sensor,
as selected. This is the parameter being audited. The Standard parameter is the field where the
correct pressure as shown on the traceable reference standard pressure audit device is entered.
Position the reference standard near the E-BAM and verify both the standard and the E-BAM values
are stable. Compare the E-BAM value to the standard. If an adjustment is necessary, enter the
correct pressure in the Standard field and then press the CALIBRATE key to correct the E-BAM
sensor reading. The E-BAM and Standard parameters should now match. Press the X key to exit
the screen when finished.
If difficulty is encountered during the process, the DEFAULT key can be pressed to erase all field
calibration factors from the selected pressure sensor and to start over with factory default calibration
factors. Then try the calibration again.
Important Note : The pressure sensors must be audited individually and with the pump off.
Selecting either pressure sensor for auditing should cause the pump to stop. If it does not, contact
the Met One Instruments service department for assistance (see section 1.2).