BAPI Duct Averaging Transmitters Catalog Page

Duct Averaging Transmitters

BA/T#-A Temperature Transmitter

Installation & Operations

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Overview

The BA/T#-A is a exible averaging duct mounted 4-20mA or Voltage transmitter probe. It comes in a variety of probe
lengths and optional mounting enclosures shown below. The 4-20mA transmitter can be ordered with 100Ω (385), 1KΩ
(385) RTDs or 10KΩ type 2 thermistor sensors. A 0-5VDC or 0-10VDC transmitter is also available with the 10KΩ type
2 thermistor sensor. Special high accuracy RTD matched transmitters (M) are available which match the sensor to the
transmitter for improved accuracy.

Identication

rev. 06/27/17

Fig 1: Flexible Probe Bracket (BA/FPB)

(Order Separately)

Fig 3: Duct Averaging Unit with Weatherproof (WP) Enclosure

Fig 2: Duct Averaging Unit with J-Box (Standard)

Fig 4: Duct Averaging Unit with BAPI-Box (BB) Enclosure

Fig 5: Duct Averaging Unit with BAPI-Box 2 (BB2) Enclosure

Specications subject to change without notice.

Fig 6: Duct Averaging Unit with Weather Tight (EU) Enclosure

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Duct Averaging Transmitters

BA/T#-A Temperature Transmitter

Installation & Operations

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Mounting

1. Place the sensor in the middle or top of the duct as shown in Fig. 7 or Fig. 8 so the exible probe can enter the duct in
a convenient place. Drill the probe and mounting holes as depicted for the enclosure being used. (Handy Box, BB,

BB2, WP, EU).

2. Insert the probe by unrolling the sensor into the duct carefully to avoid kinking the sensor. Serpentine the duct with

the sensor at least twice across the stratied air in the duct to achieve the best average temperature reading. At the
sensor reversing points a BAPI Flexible Probe Bracket (BA/FPB - order separately) can be used to support the sensor
and to avoid kinking the sensor.

3. Mount the enclosure to the duct using BAPI recommended #8 screws through a minimum of two opposing mounting
tabs provided. Weatherproof (WP) enclosures will require assembly of the mounting tabs on opposite corners. A 1/8
inch pilot screw hole in the duct makes mounting easier through the mounting tabs. Use the enclosure tabs to mark
the pilot hole locations.

4. Snug up the sensors so that the foam backing is depressed to prevent air leakage but do not over-tighten or strip the
screw threads.

Note 1: Be sure not to drill into the weatherproof enclosures (BB,BB2,WP,EU,EUO) which will violate the NEMA and/or

the IP rating.

Note 2: Be sure to use caulk or Teon tape for your conduit entries to maintain the appropriate NEMA or IP rating for your

application.

Note 3: Conduit entry for outdoor or wet applications should be from the bottom of the enclosure.

rev. 06/27/17

Fig 7: Averaging Sensor Horizontal Mount. Best for

Vertical Stratication.

Specications subject to change without notice.

Fig 8: Averaging Sensor Vertical Mount. Best for

Horizontal Stratication.

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Mounting Continued

Mounting Notes:

Note 1

Be sure not to drill into the
weatherproof enclosures (BB, BB2,
WP, EU, EUO) which will violate the

This Panel is Intentionally Left Blank

NEMA and/or the IP rating.

Duct Averaging Transmitters

BA/T#-A Temperature Transmitter

Installation & Operations

rev. 06/27/17

Note 2
Be sure to use caulk or Teon tape
on all threaded openings to maintain
the appropriate NEMA or IP rating for
your application.

Note 3
Conduit entry for outdoor or wet
applications should be from the
bottom of the enclosure.

Fig 9-A: Junction Box or No-Box NB

Mounting Holes

Fig 9:

Junction Box or No-Box (NB)

Mounting Holes

Fig 9-B: Junction Box or No-Box NB

Duct Installation

Fig 10-A: BB2 Mounting Holes

Fig 10: BAPI-Box 2 (BB2)

Enclosure Mounting Holes

Fig 10-B: BB2 Duct Installation

Fig 11-A: BAPI-Box BB Enclosure Mounting Holes Rotate 90° for Horizontal Mounting

Fig 11: BAPI-Box (BB) Enclosure

Mounting Holes, Rotate 90° for

Horizontal Mounting

Fig 11-B: BAPI-Box BB
Duct Installation

Fig 12- A:

EU or EUO Enclosure Mounting Holes

Fig 12: Weather Tight (EU or

EUO) Enclosure Mounting Holes

Specications subject to change without notice.

Fig 13: Weatherproof (WP)

Enclosure Mounting Holes

Fig 13-B:

Weatherproof Box WB

Duct installation

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Duct Averaging Transmitters

BA/T#-A Temperature Transmitter

Installation & Operations

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Wiring & Termination

BAPI recommends using twisted pair of at least 22AWG and sealant lled connectors for all wire connections. Larger gauge wire
may be required for long runs. All wiring must comply with the National Electric Code (NEC) and local codes. Do NOT run this
device’s wiring in the same conduit as high or low voltage AC power wiring. BAPI’s tests show that inaccurate signal levels are
possible when AC power wiring is present in the same conduit as the sensor wires.

rev. 06/27/17

Fig. 14: Typical RTD 4 to 20 mA Transmitter with Flying Leads

Fig. 16: Typical Thermistor 4 to 20mA Transmitter

Fig. 15: Typical RTD 4 to 20mA Transmitter with Terminals

Fig. 17: Typical Thermistor Voltage Transmitter

Diagnostics

Possible Problems: Possible Solutions:

•

Unit will not operate. - Measure the power supply voltage by placing a voltmeter across the transmitter’s (+) and

- Check if the RTD wires are physically open or shorted together and are terminated to the

- Measure the physical temperature at the temperature sensor’s location using an accurate

(-) terminal. Make sure that it matches the drawings above and power requirements in the
specications.

transmitter.

temperature standard. Disconnect the temperature sensor wires and measure the
temperature sensor’s resistance with an ohmmeter. Compare the temperature sensor’s
resistance to the appropriate temperature sensor table on the BAPI website.

• The reading is incorrect in the controller.

- For a 4-20mA current transmitter measure the transmitter current by placing an ammeter

Voltage Temperature Equation

T = TLow + (V x TSpan)
VSpan
T = Temperature at sensor
TLow = Low temperature of span
THigh = High temperature of span
TSpan = THigh - TLow
VLow = Low transmitter voltage
usually=(0, 1 or 2v)
VHigh = High transmitter voltage
usually=(5 or 10v)
VSpan = VHigh - VLow
V = Signal reading in volts

- Determine if the input is set up correctly in the controllers and BAS software.

in series with the controller input. The current should read according to the “4-20mA
Temperature Equation” shown below.

- For a voltage transmitter, measure the signal with a volt meter (Orange or Orange/Black to
Black). The signal should read according to the “Voltage Temperature Equation” shown below.

4-20mA Temperature Equation

T = TLow + (A -4) x (TSpan)
16
T = Temperature at sensor
TLow = Low temperature of span
THigh = High temperature of span
TSpan = THigh - TLow
A = Signal reading in mA

Specications subject to change without notice.

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Specications

RTD Transmitter

Power Required: 7 to 40VDC
Transmitter Output: 4 to 20mA, 850Ω@24VDC
Output Wiring: 2 wire loop
Output Limits: <1mA (short), <22.35mA (open)
Span:
Zero:

Zero & Span Adjust:

Min. 30ºF (17ºC), Max 1000ºF, (555ºC)
Min. -148°F (-100°C), Max 900ºF (482ºC)

10% of span
Accuracy: ±0.065% of span
Linearity: ±0.125% of span

Power Output Shift:

±0.009% of span
RTD Sensor: 2 wire Platinum (Pt), 385 curve

Transmitter Ambient:

-4 to 158ºF(-20 to 70ºC)

0 to 95% RH, Non-condensing

Thermistor Transmitter

Supply Voltage:

10 to 35 VDC 0 to 5 VDC or 4 to 20 mA Outputs
15 to 35 VDC 0 to 10 VDC Output
12 to 24 VAC 0 to 5 VDC Outputs
15 to 24 VAC 0 to 10 VDC Output
Transmitter Output 4 to 20mA, 700Ω@24VDC
0 to 5VDC, 0 to 10VDC, 10KΩ min
Output wiring 2 & 3 wire (see Wiring detail)
Transmitter Limits -40ºF to 185ºF,(-40ºC to 85ºC)
Accuracy ±1.015ºC, from (0 to 65ºC)
Linearity ±0.065ºC, from (0 to 65ºC)
Resolution Span/1024
Thermistor Sensor 10K-2 Thermistor,10KΩ @77ºF
Transmitter Ambient 32 to 158ºF, (0º to 70ºC)
0 to 95% RH, Noncondensing
Thermistor: 10K-2, Thermal resistor
Sensor Probe:
8 feet 4 Thermistors
12 feet 4 Thermistors
24 feet 9 Thermistors
Accuracy (Std) ±0.36ºF, (±0.2ºC)
Accuracy (High) ±0.18ºF, (±0.1ºC), [XP] option
Stability < 0.036ºF/Year, (<0.02ºC/Year)
Heat Dissipation 2.7 mW/ºC
Probe Range -40º to 221ºF (-40º to 105ºC)

Wire Colors:
Standard: Yellow/Yellow (no polarity)
High Acc. [XP]: Yellow/Yellow (no polarity)

RTD: Resistance Temp Device (Continuous)
Platinum (Pt) 100Ω and 1KΩ @0ºC, 385 curve,
Pt Accuracy (Std) 0.12% @Ref, or ±0.55ºF, (±0.3ºC)
Pt Accuracy (High) 0.06% @Ref, or ±0.277ºF,
(±0.15ºC), [A]option

Pt Stability ±0.25ºF, (±0.14ºC)
Pt Self Heating 0.4 ºC/mW @0ºC
Pt Probe Range -40º to 221ºF, (-40 to 105ºC)
Wire Colors:

General color code (other colors possible)
1KΩ, Class B Orange/Orange (no polarity)
1KΩ, Class A Orange/White (no polarity)
100Ω, Class B Red/Red (no polarity)
100Ω, Class A Red/Red-w/black stripe (no polarity)

Duct Averaging Transmitters

BA/T#-A Temperature Transmitter

Installation & Operations

rev. 06/27/17

Sensitivity: Approximate @ 32ºF (0ºC)
Thermistor Non-linier (see www.bapihvac.com,
click “Sensor Specs”)

RTD (Pt) 3.85Ω/ºC for 1KΩ RTD

0.385Ω/ºC for 100Ω RTD

Lead wire 22awg stranded

Insulation Etched Teon, Plenum rated

Probe Flexible Aluminum tube, 0.19”OD

Probe Length

Duct gasket

Mounting Extension tabs (ears), 3/16” holes

Enclosure Types: (Part number designator in bold)

J-Box: -JB, w/ eight ½” knock-outs
Weatherproof: -WP, w/ two ½” FNPT entries, (Bell box)
BAPI-Box: -BB, w/ four ½” NPSM & one ½” drill-out
BAPI-Box 2:
Weather Tight: -EU, EUO, w/ two ½” knock-outs

Enclosure Ratings: (Part number designator in bold)
J-Box: -JB, NEMA 1
Weatherproof: -WP, NEMA 3R, IP14
BAPI-Box: -BB, NEMA 4, IP66, UV Rated
BAPI-Box 2: -BB2, NEMA 4, IP66, UV Rated
Weather Tight: -EU, NEMA 4, IP66
Weather Tight: -EUO, NEMA 4, IP66, UV rated

Enclosure Material: (Part number designator in bold)
J-Box: -JB, UL94H-B
Weatherproof: -WP, Cast Aluminum, UV rated
BAPI-Box: -BB, Polycarbonate, UL94V-0, UV rated
BAPI-Box 2: -BB2, Polycarbonate, UL94V-0, UV rated
Weather Tight: -EU, ABS Plastic, UL94V-0
Weather Tight:

Ambient (Encl.) 0 to 100% RH, Non-condensing
J-Box -JB, -40ºF to 212ºF, (-40º to 100ºC)
Weatherproof -WP, -40ºF to 212ºF, (-40º to 100ºC)
BAPI-Box -BB, -40ºF to 185ºF, (-40º to 85ºC)
BAPI-Box 2 -BB2, -40ºF to 185ºF, (-40º to 85ºC)
Weather Tight -EUO, EU, -40ºF to 185ºF, (-40º to 85ºC)

Agency RoHS
PT=DIN43760, IEC Pub 751-1983,
JIS C1604-1989

8’, 12’, 24’ per order

1/4” Closed cell foam (impervious to mold)

-BB2, w/ three ½” NPSM & three ½” drill-outs

-EUO, ASA (Geloy) Plastic, UL94V-0, UV rated

Specications subject to change without notice.

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