![BAPI BA/TXS05[-40 TO 185F]-O-BB2 : 0 to 5 VDC Outside Air Temperature Transmitter, -40 to 185°F Scaled Range, BAPI-Box 2](https://cdn11.bigcommerce.com/s-ksbdsp5vfo/images/stencil/1280x1280/products/89849/135621/BAPI-51-OutsideAirUnits__84201.1787713508.png?c=1 "BAPI BA/TXS05[-40 TO 185F]-O-BB2 : 0 to 5 VDC Outside Air Temperature Transmitter, -40 to 185°F Scaled Range, BAPI-Box 2")
![Dimensions for BAPI BA/TXS05[-40 TO 185F]-O-BB2 : 0 to 5 VDC Outside Air Temperature Transmitter, -40 to 185°F Scaled Range, BAPI-Box 2](https://cdn11.bigcommerce.com/s-ksbdsp5vfo/images/stencil/1280x1280/products/89849/135622/BAPI-52-OutsideAirUnitsDimensions__95856.1787713508.png?c=1 "Dimensions for BAPI BA/TXS05[-40 TO 185F]-O-BB2 : 0 to 5 VDC Outside Air Temperature Transmitter, -40 to 185°F Scaled Range, BAPI-Box 2")
![BAPI BA/TXS05[-40 TO 185F]-O-BB2 : 0 to 5 VDC Outside Air Temperature Transmitter, -40 to 185°F Scaled Range, BAPI-Box 2](https://cdn11.bigcommerce.com/s-ksbdsp5vfo/images/stencil/500x659/products/89849/135621/BAPI-51-OutsideAirUnits__84201.1787713508.png?c=1 "BAPI BA/TXS05[-40 TO 185F]-O-BB2 : 0 to 5 VDC Outside Air Temperature Transmitter, -40 to 185°F Scaled Range, BAPI-Box 2")
Output0 to 5 VDC
Scaled Range-40 to 185°F
Power Required12 to 40 VDC
Sensing Element2 wire Platinum, 385 curve
EnclosureBAPI-Box 2 IP66 / NEMA 4
System Accuracy±0.065% of span
BAPI BA/TXS05[-40 TO 185F]-O-BB2 is an outside air temperature transmitter. A Platinum RTD, 1K-ohm @ 0°C, 385 curve reads outdoor air temperature through a vented polycarbonate shield, and the transmitter drives a 0 to 5 VDC signal scaled across -40 to 185°F (-40 to 85°C). It runs on 12 to 40 VDC over a 3 wire (PWR, GRD, Vout) termination and BAPI rates system accuracy at ±0.065% of span.
Specifications on this page are taken from BAPI datasheet “Outside Air Units” (B50-B51), Rev. 10/05/23, and from “Outside Air (OSA) Temperature Transmitters Installation & Operation” (20920_ins_OSA_Active), rev. 05/18/26. The part number and its scaled range are taken from the current BAPI price sheet; the ordering guide in the datasheet shows a subset of available ranges and states that additional options are available.
Best For
- Outdoor-mounted outside air temperature measurement
- Sites exposed to rain, snow and large temperature swings
- High humidity outdoor sites, rated 0 to 95% RH, non-condensing at the transmitter
- Controllers that accept a 0 to 5 VDC analog input
- Applications needing a scaled analog signal rather than a raw resistance input
Key Features
0 to 5 VDC OutputBAPI's ordering guide defines output code TXS05 as 0 to 5 VDC. The circuit board for voltage output units carries a 3-position DIP switch that sets the output value. BAPI sets it to order when the unit is built, and it may be changed in the field.
Scaled RangeOutput span of -40 to 185°F (-40 to 85°C). BAPI limits span to Min. 30°F (17°C), Max. 1000°F (555°C) and zero to Min. -148°F (-100°C), Max. 900°F (482°C).
Platinum RTD Sensing ElementPlatinum RTD, 1K-ohm @ 0°C, 385 curve. Sensitivity 3.85 ohm/°C, approximate @ 32°F (0°C). Sensor accuracy 0.12% @Ref, or ±0.55°F (±0.3°C). BAPI offers high accuracy RTD matched transmitters (M option) that match the sensor to the transmitter for improved accuracy.
Three-Wire Voltage Output12 to 40 VDC. 3 wire. PWR takes 12 to 40 VDC from the controller or supply, GRD is the ground for power and the voltage signal, and Vout drives the controller analog input. Two orange leads go to the internal RTD.
BAPI-Box 2 EnclosureNEMA 4, IP66. UV-resistant polycarbonate, UL94V-0. Two 1/2 in. NPSM plus three 1/2 in. drillable ports. 4.91 in. (124.8 mm) H x 2.82 in. (71.6 mm) W x 2.35 in. (59.7 mm) D.
Vented Shield ProbeVented polycarbonate shield, 1/2 in. (13 mm) OD. Probe length 2.1 in. (53 mm) with 1/2 in. (13 mm) NPT threads. 22 AWG stranded, Etched Teflon, plenum rated.
Technical Specifications
| Specification | Value |
|---|---|
| Product Type | Temperature transmitter |
| Output | 0 to 5 VDC |
| Outputs Available | 4 to 20 mA, 0 to 5, 1 to 5, 0 to 10 or 2 to 10 VDC |
| Output Selection | Field selectable by 3-position DIP switch |
| Scaled Range | -40 to 185°F (-40 to 85°C) |
| Power Required | 12 to 40 VDC |
| Output Wiring | 3 wire (PWR, GRD, Vout) |
| System Accuracy | ±0.065% of span |
| Linearity | ±(0.125 x T-20°C)/100 |
| Span Limits | Min. 30°F (17°C), Max. 1000°F (555°C) |
| Zero Limits | Min. -148°F (-100°C), Max. 900°F (482°C) |
| Transmitter Ambient | -4 to 158°F (-20 to 70°C) |
| Transmitter Humidity | 0 to 95% RH, non-condensing |
| RTD Sensor | 2 wire Platinum, 385 curve |
| RTD Element | Platinum RTD, 1K-ohm @ 0°C, 385 curve |
| RTD Sensitivity | 3.85 ohm/°C, approximate @ 32°F (0°C) |
| RTD Accuracy (Standard) | 0.12% @Ref, or ±0.55°F (±0.3°C) |
| RTD Accuracy (High) | 0.06% @Ref, or ±0.277°F (±0.15°C), [A] option |
| RTD Stability | ±0.25°F (±0.14°C) |
| RTD Self Heating | 0.4°C/mW @ 0°C |
| Probe Range | -40 to 221°F (-40 to 105°C) |
| Probe | Vented polycarbonate shield, 1/2 in. (13 mm) OD |
| Probe Length | 2.1 in. (53 mm) with 1/2 in. (13 mm) NPT threads |
| Lead Wire | 22 AWG stranded, Etched Teflon, plenum rated |
| Termination | Leadwires |
| Enclosure | BAPI-Box 2 (BB2) |
| Enclosure Rating | NEMA 4, IP66 |
| Enclosure Material | UV-resistant polycarbonate, UL94V-0 |
| Enclosure Entries | Two 1/2 in. NPSM plus three 1/2 in. drillable ports |
| Enclosure Dimensions | 4.91 in. (124.8 mm) H x 2.82 in. (71.6 mm) W x 2.35 in. (59.7 mm) D |
| Vented Sensor Guard | 2.10 in. (53.3 mm) |
| Enclosure Ambient | -40 to 185°F (-40 to 85°C) |
| Enclosure Humidity | 0 to 100% RH, non-condensing |
| Wall Gasket | 0.25 in. (6.35 mm) closed cell foam, impervious to mold |
| Agency | CE EN 61326-1:2013 EMC (industrial electromagnetic environment); RoHS |
| Standards | DIN 43760, IEC Pub 751-1983, JIS C1604-1989 |
Scaled range and ambient range are different things. This part number is scaled to -40 to 185°F, which reaches beyond the -4 to 158°F (-20 to 70°C) transmitter ambient BAPI publishes for the electronics. Confirm the installed ambient stays inside the transmitter ambient range.
Documentation
Outside Air Units Datasheet (B50-B51)Outside_Air_temp_NoPrice-v17.pdf — Rev. 10/05/23- Outside Air Temperature Transmitters Installation & Operation20920_ins_OSA_Active.pdf — rev. 05/18/26
Related Products
BAPI BA/T1K[-10 TO 70F]-O-BB2 - 4 to 20 mA Outside Air Temperature TransmitterBAPI BA/T1K[-20 TO 120F]-O-BB2 - 4 to 20 mA Outside Air Temperature Transmitter
Frequently Asked Questions
What is the output and scaled range?
BAPI's ordering guide defines output code TXS05 as 0 to 5 VDC. The range code in this part number scales that output across -40 to 185°F (-40 to 85°C).
What power does the transmitter need and how is it terminated?
12 to 40 VDC. 3 wire. PWR takes 12 to 40 VDC from the controller or supply, GRD is the ground for power and the voltage signal, and Vout drives the controller analog input. Two orange leads go to the internal RTD. BAPI recommends wiring the product with power disconnected. Incorrect supply voltage, polarity or connections may damage the product and will void the warranty.
Can the output be changed in the field?
The circuit board for voltage output units carries a 3-position DIP switch that sets the output value. BAPI sets it to order when the unit is built, and it may be changed in the field. The settings are 0 to 5 V, 0 to 10 V, 1 to 5 V, 2 to 10 V and 4 to 20 mA. BAPI notes that a unit ordered with a voltage output can be switched to 4 to 20 mA with the DIP switch, leaving the middle flying lead or middle terminal unused.
Where should the transmitter be mounted?
Mount in the shade, away from building windows, doors or vents. A sensor in direct sunlight can read higher than actual by as much as +30%. The ideal shaded location is the north side of the building in the northern hemisphere, and the south side in the southern hemisphere. Point the shield and probe down, at least four feet above the ground or roof and a minimum of one foot below the eave.
What are the accuracy and ambient limits?
BAPI rates system accuracy at ±0.065% of span with linearity of ±(0.125 x T-20°C)/100, over a transmitter ambient of -4 to 158°F (-20 to 70°C) at 0 to 95% RH, non-condensing. The sensing RTD itself is accurate to 0.12% @Ref, or ±0.55°F (±0.3°C).
What wiring does BAPI recommend?
Twisted pair, at least 22 AWG, with sealant-filled connectors. Do not share conduit with NEC Class 1, Class 2 or Class 3 AC power wiring, or with wiring supplying highly inductive loads such as motors, contactors and relays. BAPI testing shows fluctuating and inaccurate signal levels are possible when AC power shares the conduit. All wiring must comply with the National Electric Code (NEC) and local codes. Keep the transmitter at least five feet from any radio wave-emitting device. Closer than five feet can cause unwanted interference.
5 Year Warranty — Building Automation Products, Inc. (BAPI) covers this product for 5 years. Warranty service is handled through ZOT Supply as an authorized BAPI distributor.
- Product Type:
- Temperature Transmitter
- Output Signal:
- 0 to 5 VDC
- Application:
- Outside Air
- Scaled Range:
- -40 to 185°F
- Sensing Element:
- 1K Platinum RTD 385 Curve
- Power Required:
- 12 to 40 VDC
- Enclosure:
- BAPI-Box 2
- NEMA Rating:
- NEMA 4
- IP Rating:
- IP66
- Termination:
- Leadwires
- Warranty:
- 5 Year
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