BAPI Outside Air Temperature Sensors Catalog Page

Outside Air Temperature Sensors BA/#-O

Installation & Operations

20909_ins_OSA_Passive

Overview

The BA/#-O is for Outside Air mounting and temperature measurement. The probe is made to protect the sensor from
rain, sleet, snow or bird droppings. The BA/#-O is available in multiple thermistor or RTD’s as shown in the specications.
Enclosure mounting styles come in plastic or metal for both NEMA 3R and NEMA 4 applications and are all UV rated.

Identication

rev. 06/29/15

Fig 1: Outside Air Sensor in a BAPI-Box (-BB) Enclosure

Fig 3: Outside Air Sensor in a Weatherproof (-WP) Enclosure

Fig 2: Outside Air Sensor in a BAPI-Box 2 (-BB2) Enclosure

Fig 4: Outside Air Sensor in a Weather Tight (-EU) Enclosure

Specications subject to change without notice.

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Outside Air Temperature Sensors BA/#-O

Installation & Operations

20909_ins_OSA_Passive

Mounting

Fig 5: BAPI-Box (-BB) Enclosure Installation Fig 6: BAPI-Box 2 (-BB2) Enclosure Installation

rev. 06/29/15

Fig 8: Weather Tight (-EU) Enclosure InstallationFig 7: Weatherproof (-WP) Enclosure Installation

Outside Air (OSA) sensor placement is critical to good performance. The OSA sensor must be mounted in the shade
away from building windows, doors or vents. They should never be in direct sunlight or you will have higher than
expected temperature readings by as much as +30%. The ideal shaded location in the Northern hemisphere is on the
North side of the building. In the Southern hemisphere the South side of the building is ideal.

The sensor shield and probe should always point down and mounted between four feet above the ground/roof and one
foot minimum below the eave. (Note: Four feet keeps the sensor above the ground or roof top radiation and one foot
under the eave prevents measurement of trapped heat from under the eave.)

Drill the mounting holes and mount as shown in the gures 5-8. Snug up the mounting screws to ensure that the foam

backing compresses to about 50% of its thickness to make a gasket type seal against the wall surface.

Route the wires into the box and terminate with sealant lled connectors to prevent water from attacking the connection,
thereby preventing costly callbacks. Best practice is to caulk the wiring hole after the wiring is installed. Close the cover of

the BB, BB2 or WP boxes and secure with provided cover screws or twist on the cover of the EU box to the second click.

Specications subject to change without notice.

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Outside Air Temperature Sensors BA/#-O

Installation & Operations

20909_ins_OSA_Passive

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. 06/29/15

To Controller
Analog Input (AI)
(No Polarity)

Sensor

To Controller
Analog Input (AI)
(No Polarity)

Fig. 9: 2 Wire Lead Wire Termination for Thermistor or RTD

To 3 Wire Transmitter

Sensor

To 3 Wire Transmitter

Fig. 10: 3 Wire Lead Wire Termination for RTD

Fig. 11: Terminal Strip (-TS) Option for 2 Wire Sensors

Termination

Fig. 13: Test & Balance (-TB) Option for 2 Wire Sensors

Termination

Specications subject to change without notice.

Fig. 12: Terminal Strip (-TS) Option for 3 Wire

Sensors Termination

Fig. 14: Test & Balance (-TB) Option for 3 Wire

Sensors Termination

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20909_ins_OSA_Passive

Diagnostics

Possible Problem:

Controller reports higher or
lower than actual temperature

Possible Solutions:

- Conrm the input is set up correctly in the front end software

- Check wiring for proper termination & continuity. (shorted or open)

- Disconnect wires and measure sensor resistance and verify the “Sensor” output is
correct.

Specications

Sensor Passive
Thermistor NTC, 2 wire
RTD PTC, 2 or 3 wire

Thermistor Thermal resistor
Temp. Output Resistance
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
Temp. Drift <0.02ºC per year
Probe range -40º to 221ºF (-40º to 105ºC)

RTD Resistance Temperature Device
Platinum (Pt) 100Ωor 1KΩ @0ºC, 385 curve,
Platinum (Pt) 1KΩ @0ºC, 375 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)
Nickel (Ni) 1000Ω @70ºF, JCI curve
Ni Probe range -40º to 221ºF (-40 to 105ºC)

Sensitivity Approximate @ 32ºF (0ºC)
Thermistor Non-linier
Go to bapihvac.com “Sensor Specs”

1KΩ RTD (Pt) 3.85Ω/ºC
100Ω RTD (Pt) 0.385Ω/ºC
Nickel (Ni) 2.95Ω/ºF for the JCI RTD

Outside Air Temperature Sensors BA/#-O

Installation & Operations

rev. 06/29/15

Lead wire 22awg stranded
Wire Insulation Etched Teon, Plenum rated
Probe Vented polycarbonate shield, ½” OD
Probe Length
Mounting Extension tabs (ears), 3/16” holes

Wall Gasket Closed cell foam (impervious to mold)

Enclosure Types

Weather Proof -WP, w/ two ½” FNPT entries, (Bell box)
BAPI-Box -BB, w/ four ½” NPSM & one ½” drill-outs
BAPI-Box 2 -BB2, w/ three ½” NPSM & three ½” drill-outs
Weather Tight -EU, w/ two ½” drill-outs

Enclosure ratings

Weatherproof -WP, NEMA 3R, IP14
BAPI-Box -BB, NEMA 4, IP66
BAPI-Box 2 -BB2, NEMA 4, IP66
Weather Tight -EU, NEMA 4, IP66, UV rated

Enclosure materials

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,

Ambient (Enclosure) 0 to 100% RH, Non-condensing
Weatherproof -WP, -40ºF to 212ºF, (-40º to 100ºC)
BAPI-Boxes -BB, -BB2, -40ºF to 185ºF, (-40º to 85ºC)
Weather Tight -EU, -40ºF to 185ºF, (-40º to 85ºC)

Agency RoHS, CE (CE for all sensors below 10KΩ)
PT = DIN43760, IEC Pub 751-1983,
JIS C1604-1989

1.2” w/ ½” NPT threads

Plastic,

UL94V-0, UV rated

*Passive Thermistors 20KΩ and smaller are

CE Compliant

Related Products

BA/SFC1000-100 Sealant lled crimp connectors (100 connectors)
BA/SFC2000-100 Sealant lled crimp twist on wire nuts (100 nuts)

Specications subject to change without notice.

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