Land 4500 MKII Premier, Operation And Maintenance Manual

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Model 4500 Premier Dust and Opacity Monitor
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B3-8 Upscale Span Filter Adjustment
U.S. Legislation requires that the instrument is periodically checked using an Upscale Calibration
Value that is 150% to 190% of the applicable opacity standard. This is achieved using an Automatic
Span Filter. A range of gratings for the Span Filter are provided with nominal Opacities of 5%, 10%,
15%, 20%, 28%, 36%, and 45%. The instrument is factory set with a span filter of 28%.
To install an alternative filter from the set provided, follow the procedure outlined below.
Removing the Span Filter
1. Ensure that the power to the instrument is switched off.
2. Undo the two quick release clamps on the Transceiver and swing the unit open, revealing the
Automatic Zero Point Assembly.
3. Undo the hinge pins (captive in the purge assembly) using a 5mm Allen key and lift the
Transceiver away from the purge assembly.
4. Undo the sixteen M4 socket head screws holding the outer casing in place using a 3mm
hexagonal (Allen) key and partly withdraw the casing.
NOTE
A Static protection wrist band should be worn at this point
5. Disconnect the Umbilical Klippon terminal strip and remove the outer casing.
Continue to step 6.