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AD-1252 Thermal Dispersion Probe Airflow Measuring System Installation Instructions
4
Round Duct Mounting
Figure 3: Round Duct Mounting - One or Two
Probe Configurations
90°
F
IG
:A
D
1
2
52_
1or
2r
d
Figure 4: Round Duct Mounting - Three or Four
Probe Configurations
90°
45°
60°
60°
FI
G
:A
D
1
25
2_3
or4
rd
Table 2: Number of Probes/Sensors per Probe for Round Duct Applications
1
Duct Diameter, in.
No. of Probes/No. of Sensors per Probe
12
2/2
18
2/2
24
2/2
36
2/4
42
2/4
48
3/4
60
4/4
72
4/4
96
3/4
120
4/4
1.
The minimum diameter size is 12 inches for round duct applications. Round duct applications smaller than 12 inches (304
mm) use the same number of probes and sensors as the 12 inches (304 mm) size.