
B20
Duct Units
Humidity or Combination Temp/Humidity Sensors
Features & Options
l 10 Points of Calibration from 10 to 90% RH
l Humidity Only or Temp./Humidity Combination
l Replaceable Stainless Steel Filter
l
Green Power Indication LED on BAPI-Box
Crossover Units
l
2% and 3% RH Accuracies
Humidity control is an important aspect of any
climate control system. Therefore, humidity sensors
must be both accurate and dependable. BAPI’s
humidity transmitters are calibrated at 10 points
from 10 to 90% RH for accuracy, eliminating eld
calibration.
The Duct Units are also extremely dependable,
featuring two of the most watertight enclosures
available today. The BAPI-Box and BAPI-Box
Crossover Enclosures are made of UV-resistant
polycarbonate and carry an IP66 rating. The
BAPI-Box is only available for units with a
temperature transmitter and a humidity transmitter.
Rev. 03/16/18
BAPI-Box
Crossover
BAPI-Box
(only available for units with
a temperature transmitter
and a humidity transmitter)
The BAPI-Box Crossover Enclosure
The BAPI-Box Crossover features a hinged cover with thumb latch for
easy termination. A pierceable knockout plug is available for the open
port. See the Accessories section for more info.
(Unit shown with knockplug plug sold separately.)
Specications
Power and Consumption:
10 to 35 VDC, 22 mA max. (for units with 0 to 5 VDC or 4 to 20 mA Humidity Outputs)
15 to 35 VDC, 6 mA max. (for units with 0 to 10 VDC Humidity Output)
12 to 27 VAC, 0.53 VA max. (for units with 0 to 5 VDC Humidity Outputs)
15 to 27 VAC, 0.14 VA max. (for units with 0 to 10 VDC Humidity Output)
Enclosure Dimensions: H x W x D
BAPI-Box Crossover:.................3.1 x 2.2 x 1.9” (79 x 56 x 49mm)
BAPI-Box ...................................5 x 4.1 x 2.5” (127 x 104 x 63.5mm)
(For enclosure dimension drawings, turn to the end of the section.)
Sensor:
Humidity:
Capacitive 2% or 3%RH
(10 to 90% RH @ 23°C)
Temperature:
Thermistor or RTD
(See Sensors section for specs)
Enclosure Rating:
BAPI-Box Crossover: IP10, NEMA 1
(IP44 with knockout plug)
BAPI-Box: IP66, NEMA 4X
Enclosure Material:
UV-res. Polycarbonate, UL 94, V-0
Environmental Operation Range:
Temp: -40 to 158°F (-40 to 70°C)
Humidity: 0% to 100% RH
Fully Temperature Compensated

Duct Units
Humidity or Combination Temp/Humidity Sensors
Use the Option Selection Guide below to create your custom part number. Replace the number and
parenthesis with the designator for each selection. Skip the designator and dashes for optional selections
that are not required in your conguration.
Duct Humidity Sensor Option Selection Guide
BA/ ( #1 ) - ( #2 ) - ( #3 )
#1: Temperature Sensor or Transmitter (optional)
1.8K ............................1.8K Thermistor
3K ...............................3K Thermistor
10K-2 ..........................10K-2 Thermistor
10K-3 ..........................10K-3 Thermistor
10K-3[11K] ..................10K-3[11K] Thermistor
20K .............................20K Thermistor
1K[375] .......................1K Platinum RTD (375 curve)
1K[NI]..........................1K Ω Nickel RTD
1K ...............................1K Platinum RTD (385 curve)
Temperature Transmitters below require a BAPI-Box Enclosure
T1K[32 TO 212F] ........1K Plat. RTD Transmitter, 4 to 20 mA Output, 32 to 212°F Range
T1K[20 TO 120F] ........1K Plat. RTD Transmitter, 4 to 20 mA Output, 20 to 120°F Range
T1K[0 TO 100F] ..........1K Plat. RTD Transmitter, 4 to 20 mA Output, 0 to 100°F Range
T1K[0 TO 100C] .........1K Plat. RTD Transmitter, 4 to 20 mA Output, 0 to 100°C Range
T1K[-7 TO 49C] ..........1K Plat. RTD Transmitter, 4 to 20 mA Output, -7 to 49°C Range
T1K[-18 TO 38C] ........1K Plat. RTD Transmitter, 4 to 20 mA Output, -18 to 38°C Range
Matched Transmitters are also available. Contact your BAPI representative for ordering.
B21
#2: Humidity Output (required)
H200 .......... ±2% Humidity Transmitter with Interchangeable Output of 0 to 5 V or 4 to 20 mA
H210 .......... ±2% Humidity Transmitter with 0 to 10 V Output
H212 .......... ±2% Humidity Transmitter with 2 to 10 V Output
H300 .......... ±3% Humidity Transmitter with Interchangeable Output of 0 to 5 V or 4 to 20 mA
H310 .......... ±3% Humidity Transmitter with 0 to 10 V Output
H312 .......... ±3% Humidity Transmitter with 2 to 10 V Output
#3: Enclosure Style (required)
D-BBX.........................BAPI-Box Crossover (IP10, NEMA 1)
D-BB ...........................BAPI-Box (for units with a humidity and temperature transmitter only)
Example Number: BA/( 10K-2 ) - ( H200 ) - ( D-BBX )
Actual Number (with parenthesis removed): BA/10K-2-H200-D-BBX
Description: 10K-2 Thermistor, 0 to 5V or 4 to 20mA Humidity Output, BAPI-Box Crossover IP10-
rated Enclosure.
Your Number: BA/