Ametek Land 4500 MKIII, User Manual

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Opacity and Dust Monitor
User Guide
Model 4500 MkIII
B - 30
The External Zero Device (EZD) is used during the Re-calibration routine
when true clear stack conditions are unobtainable.
Follow the steps outlined in Section 5.4, being careful NOT to move the
sliding adjusting plate on the back of the EZD.
Before step 7 (Confirm Clear Path), fit the EZD (with the arrow pointing
upwards) as shown in the photograph below. Tighten the clamping screw to
hold the EZD securely. Remove the EZD before continuing to Step 8 (Confirm
Blocked Path)
External Zero Device fitted to Model 4500 Mk III
B5.9 Recalibrating the External Zero Device (EZD)
All instruments are shipped out from the factory configured to customers’
requirements. Re-calibration of the EZD is required immediately after re-
calibration of the instrument. It is recommended that re-calibration is
performed every three years or if a Calibration Audit shows the instrument
to be outside of acceptable limits. Please ensure that all optical surfaces
are clean and the optical path is not obstructed before performing any
calibration.
If the flange to flange path length is altered (i.e. due to relocation of the
instrument) contact Land Instruments International customer services for
instrument pathlength setup advice.
IMPORTANT
Re-calibration should be carried out under clear stack conditions
or in a laboratory with the Transceiver set to the correct flange-to-
flange path length.
The EZD should be re-calibrated following a genuine
recalibration of the instrument only (recommended every
three years).
If in any doubt about these instructions, please contact Land Instruments
International Customer Services Department before proceeding. Take care
when handling the reflective surfaces as they can easily be scratched or
made dirty.