CASELLA CEL CEL-712 - Servicing Hints

CEL-712 Microdust Pro Real-time Dust Monitor
57 Casella Measurement
9.3 Servicing hints
There are no user-serviceable parts inside the Microdust Pro instrument or
sampling probe. DO NOT open these items.
WARNING
CLASS 1 LASER PRODUCT
The Microdust Pro instrument is an enclosed Laser based system.
The internal laser radiation is the equivalent of Class 2 under normal conditions and
potentially 3B under fault conditions.
Laser Source <20mW @ 635 nm.
Risk of Visible Laser Radiation when opened. Avoid exposure to beam.
This product shall only be opened by authorised and competent personnel.
IMPORTANT
If you suspect the instrument has an electrical fault, or if a fault persists after you
perform the servicing hint listed below, return the instrument to Casella for repair.
Table 1 Servicing hints
Fault symptom
Possible cause
Service hint
The instrument does not
switch ON.
Batteries are discharged.
Replace or Recharge the
batteries.
Use an external power supply.
The probe always reads zero.
A fault may exist on the laser
transmitter or receiver.
Check the probe connection.
There is a continuous ‘over
range’ indication.
Optical misalignment due to
mechanical shock.
Excessive contamination.
If repeated purging of the
probe with clean air does not
fix the pr0blem then please
return the instrument to
Casella or your local Casella
representative for optical
alignment, cleaning and
re-calibration.
Zero is unstable or drifts when
the probe collar covers the
sampling chamber.
Sample chamber
contamination by dust.
Follow the technique in
section 9.1 Lens
contamination on page 55 to
clean the sample chamber.
Follow the technique in
Setting for Zero on page 28.
A probe contamination
message is displayed.
Optical misalignment due to
mechanical shock.
Excessive contamination.
Purge the probe with clean air
from the bellows pump.