Ametek Land 4200, Руководство пользователя

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User Guide Model 4200 Dust & Opacity Monitor
Ensure that the instrument is correctly aligned and the optical path is clear.
1) Remove the top cover plate on the transmissometer.
2) The display must be blank (normally the software operates a time out
facility after 10 minutes). The blank screen can also be displayed by
stepping through the menu.
Press and hold the Mode key (5 seconds) until the display indicates Ixxx ,
the value on the right hand side should normally be around 500 if still
correctly aligned. Check the reflected light spot is in the centre of the
target viewed through the sighting hole. (See the alignment procedure if
necessary).
Note: In this mode (align) the target light is continuously illuminated.
3) Press and hold the Mode key (5 seconds) until the word 'Zero' appears on
the display. The target light will now be flashing.
4) Press and hold the Mode key again (approx 2 seconds until decimal points
start to flash). This initiates the zero calculation.
5) At the end of the zero measurement the word 'Span' (ie 100% opacity) is
displayed.
6) For instruments with a path length less than 5 metres: place the zero
reflector holder (supplied as a separate item) into the filter holder position
nearest the stack with the blank side (non reflective) nearest the display.
For instruments with a path length greater than 5 metres: remove the
top plate from the retroreflector assembly. The retroreflector element is
attached to this plate. Its removal eliminates the possibility of any reflected
light causing errors in calibration.
7) Press the Mode key and hold until the decimal points on the display start
to flash, release the key. After a short period the decimal point lights will
stop flashing and the word 'bal' (Balance) appears on the display. See the
BALANCE note below.
8) Place the Zero reflector in the holder so that the side with the reflector on is
now facing the display end and replace into the same filter holder position
as before.
9) Press the Mode key until the decimal points on the display flash.
10) On completion of the balance measurement the opacity reading is restored.
When the zero reflector holder is removed the true stack value will be
displayed.
11) Replace the cover plate (and the retroreflector top plate if necessary)
The Model 4200 is now correctly calibrated for opacity.
Note
BALANCE - This measurement is taken so that a compensation factor can
be placed in the software to compensate for the difference in reflectivity
between the reflector on the zero reflector holder and the retro-reflector is
accounted for.