Land 4500 MKII Premier, Руководство по эксплуатации и обслуживанию

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Model 4500 Premier Dust and Opacity Monitor
64
B3 Periodic Modes of Operation
B3-1 Calibration Check
11
1 2 8 9
3 6 7 4
10
5
Transceiver
Key
1.
Source LED 7. Detector D
r
2. Flood LED 8. Concave Mirror
3. 50/50 Beam Splitter 9. Span Filter
4. Collimating Lens 10. Zero Point Reflector
5. Collimated Beam 11. Automatic Fail Safe Shutter (Optional)
6. Detector D
m
The Transceiver periodically performs a two step calibration check. In the first step, a zero-point reflector
(10), mounted within the air purge of the Transceiver is placed into the optical axis. In the second step, the
span filter (9) is also placed in the light path. The monitor reads the difference in light between the current
zero–point and the zero–point established during the last clear stack calibration, and notes this value as the
amount of drift and optical dust build-up. The opacity value of the span filter (9) is shown on the calibration
certificate which accompanies the instrument.
CAUTION
Do not attempt to move the zero point reflector by hand. The precision gearbox will
be irreparably damaged.