Sierra Monitor Corporation 4501-05 - Manual (Page 10)

Model 4501-XX Toxic Gas Sensor Module
Page 6 of 35
4. INSTALLATION
4.1 SENSOR MODULE LOCATIONS
The gas sensor module utilizes a diffusion type sensor which
should be located close to either the expected source or
destination of the gas hazard. If the gas is heavier than air, the
sensor module should be installed within 24 inches of the ground
or floor. If it is lighter than air, move it above 6’.
After optimum locations are determined based on the above
recommendations, consideration should be given to placing the
sensor modules in locations which are accessible for calibration
service. Slight adjustments to the location of the sensor module
may have little impact on effectiveness but major effect on
accessibility.
• Modules should be placed in areas accessible for
calibration.
• The cover should face out from the wall for easy access.
• Sensors should be pointed down and the conduit should
include an inverse trap to reduce moisture (condensation)
from accumulating in the electronics enclosure.
Model Gas Specific Gravity
N/A Air 1.00
4501-04 CO 0.97
4501-05 H
2
S 1.19
4501-06 Cl
2
2.49
4501-08 ClO
2
3.09
4501-10 SO
2
2.26
4501-12 NO
2
1.59
4501-25 NH
3
0.60
4501-26 HF 1.86
Table 4 - 1: Specific Gravities
Figure 4 - 1: Typical Mounting Options