System Sensor DH400ACDCIHT User Manual
Page 2

[2] Figure 1. Exploded View Of Duct Detector Components:
[3] Contents Of The Duct Detector Kit
1. Complete housing base and cover assembly
2. Two #10 sheet metal mounting screws
3. Two sampling tube filters
4. One test magnet
5. Drilling template
6. Two 5/16 O-rings
7. Two rubber tube bushing seals
8. Four #6 self-tapping mounting screws for the sampling
and optional exhaust tube extension
9. One filter adapter
10. One inlet tube end plug
11. Two #10 speed nuts
12. One test coil and parts bag
NOTE: The inlet sampling tube must be ordered sepa-
rately. It must be the correct length for the width
of the duct where it will be installed. See Table 1
on page 4 to determine the inlet tube required for
different duct widths.
[4] Installation Sequence
Step Page
[4.1] Verify duct air flow direction and velocity 2
[4.2] Drill the mounting holes 3
[4.3] Secure the detector housing to the duct 3
[4.4] Install the sampling tube 3
[4.5] Complete the field wiring 5
[4.6] Install the filters and check pressure differential 5
[4.7] Perform detector check 5
[4.8] Install the cover 8
[4.1] Verify Duct Air Flow Direction And Velocity
Model DH400ACDCIHT detectors are designed to be used
in air handling systems having air velocities of 500 to 4000
feet per minute. Be sure to check engineering specifications
to ensure that the air velocity in the duct falls within these
parameters. If necessary, use a velocity meter to check the
air velocity in the duct.
[4.2] Drill The Mounting Holes
Remove the paper backing from the mounting template
supplied. Affix the template to the duct at the desired
mounting location. Make sure the template lies flat and
smooth on the duct. Center punch holes A and B. Drill the
holes as indicated on the template. Slide the two speed nuts
over the two small holes (hole A) next to the sampling tube
bushing holes (hole B) previously drilled in the duct. (See
Figure 3.)
D400-64-00 2 I56-991-08R
SAMPLING TUBE
FILTERS
CONDUIT HOLES
DUCT DETECTOR
HOUSING
TERMINAL STRIP
PC BOARD
INSULATOR
DUCT DETECTOR
COVER
SAMPLING TUBE
MOUNTING
SCREWS
DETECTOR HEAD
EXHAUST
FILTER ADAPTER
DETECTOR BASE
INLET SAMPLING TUBE
(SUPPLIED SEPARATELY)
O-RINGS
FOAM
GASKETS
HOUSING
MOUNTING SCREWS
TEST MAGNET
TUBE
END
PLUG
H0237-00