Land 4500 MKII Premier, Operation And Maintenance Manual

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Model 4500 Premier Dust and Opacity Monitor
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8 Read and record the displayed opacity value. The instrument should read a value within ±1.0 % of
the calibration filter.
Note that this value will be corrected for the Optical Path length Ratio
(OPLR) . If the OPLR is set to the default value of 0.5, then the displayed value should match the
filter opacity. If the OPLR is not 0.5, then calculate the corrected value using the formula given
below.
Note: The operating wavelength of the Model 4500 Premier is 525 nm. All audit
filters will be calibrated at this wavelength.
9 Remove the filter; insert, read and record the values for the other filters in turn as required by the
procedure.
10 Remove the neutral density filter and close the transceiver.
11 The message “ENTER when done” is displayed. Press the ENTER key to complete the calibration
audit.
12 Press the MAINTENANCE key for 2 seconds to exit maintenance mode. The red LED will go out.
Modbus communications are the restored.
Calibration Audit Method 2 (Modbus communications are maintained)
1 Press and hold the EXIT key for 5 seconds.
2 The zero reflector is driven into its working position. The displayed value should be 0.00 ± 0.010.
Note that this is fractional Opacity, i.e. 100 % is shown as 1.00.
3 Open the transceiver housing by releasing two quick-release clamps, and swing the instrument
open on its hinges.
4 Insert a calibrated neutral density filter into slot 1.
5 Read and record the displayed opacity value. The instrument should read a value within ±1.0 % of
the calibration filter.
Note that this value will be corrected for the Optical Path length Ratio
(OPLR) . If the OPLR is set to the default value of 0.5, then the displayed value should match the
filter opacity. If the OPLR is not 0.5, then calculate the corrected value using the formula given
below.
6 Remove the filter, and insert, read and record the values for the other filters in turn as required by
the procedure.
7 Remove the neutral density filter and close the transceiver.
8 Press and hold the Maintenance key unit the red LED illuminates (about 5 seconds.)
9 Press the MAINTENANCE key for 2 seconds to exit maintenance mode. The red LED will go out.
OPLR correction formula
Refer to section B1-4-3 for instructions on finding the OPLR for your instrument.
OPLR
1
opacity) filter - (1 - 1 Reading Instrument
=