Land 4500 MKII Premier, Operation And Maintenance Manual

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Model 4500 Premier Dust and Opacity Monitor
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6 Align the Transceiver
Transceiver Alignment Target
1. Observe the alignment target through the window (3). A bright green spot (4) should be visible.
2. To move the green spot horizontally adjust M12 nut (1) on the air purge flange and to move it
vertically, adjust the M12 nuts (2), also on the air purge flange as illustrated above. Adjust
these nuts until the green spot is inside the inner circle.
3. In bright sunshine the green spot on the alignment target may not be visible. In this case return
to the Retro-Reflector, undo the quick–release clamps and swing open the rear cover. It should
now be possible to adjust the transmissometer until the bright circle of sunlight, visible through
the Retro-Reflector purge unit is centred on the target. Close the Retro-Reflector again. If the
green spot is visible, adjust the nuts until it is central in the inner circle. If this is not possible,
then adjust for maximum signal level.
4. Ensure that the 6 pairs of spring washers between the air purge flange and the mounting
flange are under moderate compression. If the compression becomes excessive, it is likely
that the third nut has been over tightened or the mounting flange may not have been fitted
accurately.
5. On the User interface press the Maintenance key and hold for 1 second to exit. The red LED will
be extinguished.
Once the instrument has been correctly aligned configure the calibration options.
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