Honeywell Sensepoint XCD RTD Technical Note

Description

Part Number

Quantity

Sensor Duct Adapter

1283-1048

1

Flow Restrictor

1283-1091

1

Washer, #8 Nylon

0950-0079

2

Gasket, #8 Sealing

105637

2

Screw, 8 x ¾, self-tapping

0950-0080

2

O-ring, 7/8 I.D. x 1-1/8 O.D.

0235-1135

2*

O-ring, Sensor

0235-1130

2*

O-ring, Sensor

0235-1131

2*

Duct Mount Adapters

1998-0880 Rev 1

2014

Technical Note

September

For Duct Mounting XCD-RTD, XCD-RFD, Sensepoint Toxic,
Sensepoint Combustible, 705 and XNX w/705

Duct Mounting Kit 1283-1047

The duct mounting assembly allows installation of sensors directly into ducts with diameters from 3 to 16
inches (8 to 40 cm). The installation uses a minimum number of holes drilled into the ductwork, and
allows quick changeover for exchanging sensors. (Refer to Figure 1)

This technical note provides installation instructions for mounting the sensor duct adapter. A hole
diagram is shown in Figure 3 .

The duct mounting adapter assembly is designed to divert 700cc of sample flow to a sensor over a wide
variety of duct diameters and flow rates. For installations with high flow rates, an adjustable flow
restrictor (included) is attached to the duct adapter. Use the charts (Table 1) to determine the restrictor
settings. The restrictor adjustment settings are shown in Figure 2.

The duct mounting kit (P/N 1283-1047) includes the following:

*Only one item is required; kit contains a spare of this part.

Technical Note 1998-0880

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Technical Note

Figure 1 – Duct Mounting Adapter

Installation

Use the chart shown in Table 1 to determine if you need to add the flow restrictor to the duct adapter.
If you need the restrictor, install it onto the pitot tubes (the portion of the duct adapter that goes into
the duct). Refer to Figure 2. The pitot tubes have scribed lines which represent Restrictor Lines A
through C. Restrictor Line C offers the most restriction, and is the line closest to the end of the pitot
tubes. Align the chamfered edge of the restrictor with the proper line before tightening the set screw.
Also, make certain the set screw is downstream of the air flow.

Figure 2 – Setting the Flow Restrictor

Technical Note 1998-0880

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Caution:

insulators provided in this kit.

2.50 Inches (63.5 mm)

Screw mounting holes
must be parallel with
airflow +/- 5°.

7/8 - inch

(22 mm)

9/64 - inch

(3.6 mm)

NOTE: This drawing is NOT TO SCALE

1/4-inch tubing is required, and the total length should be less than 2 feet.
Adjust the position of the restrictor until the flow is 700 cc/min, +/- 100 cc/min.

Pressure drop differential:

0.3 inches H20

Duct Wall

Mass Flowmeter
(Sierra Instruments, Inc Model
822-13-OV1-PV1-V1 or equiv)

Technical Note

Duct mounting is simple. Figure 3 shows the hole pattern. One 7/8-inch (22 mm) hole and two smaller
9/64-inch (3.6 mm) holes for #8 sheet metal screws are the only installation intrusion to the ductwork.
The sheet metal screw holes must be parallel within +/- 5° of the direction of air flow in the duct.

To prevent an earth loop, ensure the duct adapter center does
not come in contact with metal ductwork. Use the O-rings and

Figure 3 – Hole Diagram for Duct Mounting Adapter

If the flow in the duct is not known, you must connect a mass flowmeter to the duct adapter as shown in
Figure 4. Do not use a rotometer or ballmeter.

Important:

Figure 4 – Connecting a Mass Flowmeter to Duct Adapter

Technical Note 1998-0880

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