System Sensor DH500 Installation Sequence, Drill the Mounting Holes, Mount Duct Housing

Figure 1:

	CONDUIT HOLES
FOAM	INLET SAMPLING TUBE
GASKETS	(SUPPLIED SEPARATELY)

TUBE

END

PLUG

O-RINGS

DETECTOR BASE

HOUSING

MOUNTING SCREWS

EXHAUST

FILTER ADAPTER

DETECTOR HEAD

(SUPPLIED SEPARATELY)

SAMPLING TUBE

DUCT DETECTOR

HOUSING

TERMINAL STRIP

DUCT DETECTOR

COVER

SAMPLING TUBE

MOUNTING

SCREWS

TEST MAGNET

FILTERS

H0297-00

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 to determine the inlet tube required for different duct widths. Smoke detector heads (1551, ionization; 2551, photoelectronic) must be ordered separately.

Installation Sequence		Page
Step 1.	Verify duct air flow direction and velocity	2
Step 2.	Drill the mounting holes	3
Step 3.	Secure the housing base to the duct	3
Step 4.	Install the inlet sampling tube	3
Step 5.	Field wiring	5

Step 6.	Install the filters and check pressure differential 5
Step 7.	Perform detector check	7
Step 8.	Install the cover	8
Step 9.	Perform the final system check (Testing)	8

Step 1. Verify Duct Air Flow Direction and Velocity The DH500 is 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 neces- sary, an Alnor Model 6000-P velocity meter, Dwyer 460 dif- ferential pressure gauge, or their equivalent, may be used to check the air velocity in the duct.

Step 2. Drill the Mounting Holes

Remove the paper backing from the top and bottom of the template. Affix the template to the air duct at the desired mounting location. Make sure the template lies flat and smooth on the air duct. Center punch hole targets and remove the template. 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 2.)

Step 3. Mount Duct Housing

Remove the duct housing cover. Slide the foam gaskets over the tube bushings as shown in Figure 2B. Make sure the two small holes in the gaskets line up with the two base mounting holes. Put one 5/16-inch O-ring over each of the two #10 sheet metal screws. Use the two sheet metal screws to secure the duct housing to the duct.

CAUTION

Do not overtighten the screws.

D500-08-00 2 I56-512-07R