envea STACK 602, Руководство пользователя

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STACK 602 9 Maintenance
ENVEA UK Ltd
(PC-000848-MA Issue 5, December 2021)
vii
2a. The Received Light level is saturating the Rx (level fixed at 118): in this
case, no scintillation (SC) signal will be generated, and so the dust
reading is zero.
2b. The sensor has become misaligned, and the Received Light level at the
Rx is very low (level fixed at <1): in this case, the
‘ Dust ’ reading may be
very large but will be a noise reading not representative of the actual
dust level.
3. The following checks and adjustments commonly resolve the above issues:
3a.
If you suspect a problem with the setup, repeat the alignment procedure
detailed in
3b.
Appendix
A (see page
57
for instructions).
3c. Excessive stack vibration can generate false high readings.
3d. An insufficiently grounded sensor can produce false high readings.
3e. Visible moisture and heat haze can generate false high readings.
3f. [If used for measuring dust concentration] Adjust the Cal Factor to scale
the sensor reading. Dust monitors do not provide a reading pre-
calibrated to mg/m³. See
Appendix B
(page
61
) for further information
and instructions.
NOTE
: The grounding of the sensor heads is not usually an issue for this measurement
technique.