
MRK-D-0034 V2.0
Aeroqual AQM 65 User Guide
Page | 63
4.4.7 Zero calibration check and flow check of Particle Module
Tools required
AQM R56, AQM R7
Parts required
None
Frequency of
service
Recommended
Every three months
(See Section 4.6)
Online
reference
training.aeroqual.com
: Dust Monitor technical training Section 4.4
Online video
https://vimeo.com/ 78669407 checked
4.4.7.1
Check zero baseline of Particle Monitor
The Particle Monitor has an automatic zero calibration function which runs every 12 hours. This
procedure automatically changes the zero offset of the Particle Monitor.
The zero response of the Particle Monitor can be checked by removing the TSP head and placing the
R56 adaptor and zero filter assembly on the inlet above the cyclone as shown in Figure 4-16. The
Particle Monitor should read between ±3 µg m
-3
.
If the zero check shows negative numbers, there may be a problem with the auto zero cycle. See the
troubleshooting section in Appendix 1.
Check that the gain and offset values for the Particle Monitor are set to sensible settings. The gain
should be between about 0.6 and 4.0. The offset should be 0.000.
See Section 6 for a discussion on gain adjustment of the Particle Monitor.
Figure 4-16 The zero filter is fitted above the cyclone for a Particle Monitor (left) and directly on the inlet
for a Particle Profiler (right)