D200-39-00 5 I56-1977-004R
[9.1] Smoke Entry Tests
[9.1.1] Air Flow
This product is designed to operate over an extended air speed range of 100
to 4000 FPM. To verify sufficient sampling of ducted air, turn the air han-
dler on and use a manometer to measure the differential pressure between
the two sampling tubes. The differential pressure should measure at least
0.0015 inches of water and no more than 1.2 inches of water. Because most
commercially available manometers cannot accurately measure very low
pressure differentials, applications with less than 500 FPM of duct air speed
may require one of the following: 1) the use of a current-sourcing pressure
transmitter (Dwyer Series 607) per Section 9.1.4 or; 2) the use of aerosol
smoke per section 9.1.2.
[
9.1.2] Air Flow Test using Aerosol Smoke
This test is intended for low-flow systems (100-500 FPM). If the air speed
is greater than 500 FPM, use a conventional manometer to measure differ-
ential pressure between the sampling tubes, as described in 9.1.1.
Drill a
1
⁄
4
″
hole 3 feet upstream from the duct smoke detector. With the
air handler on, measure the air velocity with an anemometer. Air speed
must be at least 100 FPM.
Spray aerosol smoke* into the duct through the
1
⁄
4
″
hole for five seconds. Wait two minutes for the duct smoke detector
to alarm. If the duct smoke detector alarms, air is flowing through the
detector. Remove the duct smoke detector cover and blow out the residual
aerosol smoke from the chamber and reset the duct smoke detector. Use
duct tape to seal the aerosol smoke entry hole.
*Aerosol smoke can be purchased from Home Safeguard Industries,
Malibu, CA. Phone: 310/457-5813.
[9.1.3] Smoke Entry Test
To determine if smoke is capable of entering the sensing chamber, visually
identify any obstructions. Plug the exhaust and sampling tube holes to
prevent ducted air from carrying smoke away from the detector head, then
blow smoke such as cigarette, cotton wick, or punk directly at the head to
cause an alarm. REMEMBER TO REMOVE THE PLUGS AFTER THIS TEST,
OR THE DETECTOR WILL NOT FUNCTION PROPERLY.
[9.1.4] Air Flow Test using Dwyer Series 607 Differential Pressure
Transmitter
Verify the air speed of the duct using an anemometer. Air speed must be at
least 100 FPM. Wire the Dwyer transmitter as shown in Figure 8. Connect
the leads of the meter to either side of the 1000
Ω
resistor. Allow unit to
warm up for 15 seconds. With both HIGH and LOW pressure ports open
to ambient air, measure and record the voltage drop across the 1000
Ω
resistor (measurement 1), 4.00 volts is typical. Using flexible tubing and
rubber stoppers, connect the HIGH side of the transmitter to the sampling
tube of the duct smoke detector housing, and the LOW side of the trans-
mitter to the exhaust tube of the duct smoke detector housing. Measure
and record the voltage drop across the 1000
Ω
resistor (measurement 2).
Subtract the voltage recorded in measurement 1 from the voltage recorded
in measurement 2. If the difference is greater than 0.15 volts, there is
enough air flow through the duct smoke detector for proper operation.
Figure 8. Procedure for verifying air flow:
DIFFERENTIAL
PRESSURE
TRANSMITTER
MODEL #607-01
HIGH
LOW
TO SAMPLING TUBE
TO EXHAUST TUBE
VOLT METER
FLUKE MODEL 87
OR EQUIVALENT
1000 OHM 5% 1 WATT RESISTOR
9 VOLT
BATTERY
9 VOLT
BATTERY
9 VOLT
BATTERY
15 TO 36VDC
SUPPLY
H0163-01
[9.1.5] Filter Replacement
The filters do not substantially affect smoke performance even when up
to 90% of the filter is clogged. Quarterly visual inspection usually suf-
fices to determine whether the filters should be replaced because only a
high percentage of contamination affects performance. If further testing
is required, compare differential pressure readings with and without the
filters installed. If the difference exceeds 10% replace the filters. In no case
should the pressure differential fall below 0.0015 inches of water.
Figure 9. Wiring Diagram for DH200RPL Duct Smoke Detector using a UL listed control panel:
NOTE:
Jumper J1 shunt must be installed for 2-W applications. J1 shunt must be removed for power PCB supervision.
+
–
COM (+)
COM (-)
COM (+)
COM (-)
COMMUNICATION
LINE
UL LISTED CONTROL
PANEL
1ST DETECTOR
IN LOOP
2ND DETECTOR
IN LOOP
1 2
1 2
J1 JUMPER
J1 JUMPER
NOTE: J1 JUMPER MUST
BE INSTALLED FOR 2W
APPLICATIONS. THE
J1 JUMPER MUST BE
REMOVED FOR POWER
BOARD SUPERVISION.
