
Rigid Averaging Duct Temperature Sensors (BA/# -RA)
20904_ins_DuctAvgRigid_Passive_Passive
Overview and Identication
The Rigid Averaging Unit is for duct mounting and
temperature measurement of stratied air across the duct
to give the average temperature along the length of the
sensor.
The rigid Stainless Steel Probe is made in different
lengths for a custom duct t. The units is available
in multiple thermistor or RTD types as shown in the
specications. Enclosure mounting styles come in plastic
or metal for both NEMA 1 and NEMA 4 applications and
are all plenum rated.
Installation & Operations
rev. 06/29/15
Fig 1: Unit with No Box (NB)
Fig 2: Unit with J-Box (Standard)
Fig 4: Unit with BAPI-Box (BB) Enclosure
Fig 3: Unit with Weatherproof (WP) Enclosure
Fig 5: Unit with BAPI-Box 2 (BB2) Enclosure
Fig 6: Unit with Weather Tight (EU) Enclosure
Specications subject to change without notice.
Fig 7: Unit with BAPI-Box 4 (BB4) Enclosure
(A Pierceable Knockout Plug is available from BAPI
for the open port in the BB4. Part #BA/PKP-100)
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Rigid Averaging Duct Temperature Sensors (BA/# -RA)
Installation & Operations
20904_ins_DuctAvgRigid_Passive_Passive
Mounting
1. Place the sensor in the middle of the duct away from temperature stratied air, coils or humidiers to achieve the best
temperature reading.
2. Drill the probe hole as depicted below for the enclosure being used. Insert the probe into the duct.
3. Mount the enclosure to the duct using BAPI recommeded #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.
rev. 06/29/15
Fig 8: Junction Box or No Box
(NB) Mounting Holes
Fig 11: Weather Tight (EU or
EUO) Enclosure Mounting Holes
Fig 9: BAPI-Box 2 (BB2)
Enclosure Mounting Holes
Fig 12: Weatherproof (WP)
Enclosure Mounting Holes
Fig 10: BAPI-Box (BB) Enclosure Mounting
Holes, Rotate 90° for Horizontal Mounting
Fig 13: BAPI-Box 4 (BB4) Enclosure
Mounting Holes
Specications subject to change without notice.
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Rigid Averaging Duct Temperature Sensors (BA/# -RA)
Installation & Operations
20904_ins_DuctAvgRigid_Passive_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.
To Controller
Analog Input (AI)
(No Polarity)
Thermistor
or RTD
Sensor
To Controller
Analog Input (AI)
(No Polarity)
rev. 06/29/15
Fig. 14: 2 Wire Lead Wire Termination for Thermistor or RTD
Fig. 16: Terminal Strip (-TS) Option for 2 Wire Sensors
Termination
Fig. 15: 3 Wire Lead Wire Termination for RTD
Fig. 17: Terminal Strip (-TS) Option for 3 Wire
Sensors Termination
Fig. 18: Test & Balance (-TB) Option for 2 Wire Sensors
Termination
Specications subject to change without notice.
Fig. 19: Test & Balance (-TB) Option for 3 Wire
Sensors Termination
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20904_ins_DuctAvgRigid_Passive_Passive
Diagnostics
Rigid Averaging Duct Temperature Sensors (BA/# -RA)
Installation & Operations
rev. 06/29/15
Problems:
Controller reports higher or lower
than actual temperature
Possible Solutions:
- Conrm 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.
Specications
Sensor 4 sensors per probe
Passive Thermistor 2 wire
Passive RTD, 2 or 3 wire
Thermistor Thermal resistor (NTC)
Temp. Output Resistance per order
Accuracy (Sstd) ±0.36ºF, (±0.2ºC)
Accuracy (Hi) ±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 Temp Device (PTC)
Platinum (Pt) 100Ω and 1KΩ @0ºC, 385 curve,
Platinum (Pt) 1KΩ @0ºC, 375 curve
Pt Accuracy (Std) 0.12% @Ref, or ±0.55ºF, (±0.3ºC)
Pt Accuracy (Hi) 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
Thermistor Non-linear
Go to bapihvac.com “Sensor Specs”
RTD (Pt) 3.85Ω/ºC for 1KΩ RTD
0.385Ω/ºC for 100Ω RTD
Nickel (Ni) 2.95Ω/ºF for the JCI RTD
Lead Wire 22awg stranded
Insulation Etched Teon, Plenum rated
Probe Rigid Stainless Steel, 0.25” OD
Probe Length 12”, 2’, 4’ per order
Duct gasket 1/8” foam (impervious to mold)
176ºF Max
Mounting Extension tabs (ears), 3/16” holes
Enclosure Types
J-Box -JB, w/ eight ½” knockouts
No Box -NB, intended for open wiring
Weatherproof -WP, w/ two ½” FNPT entries, (Bell box)
BAPI-Box -BB, w/ four ½” NPSM & one ½” drill-out
BAPI-Box 2
BAPI-Box 4:
-BB2, w/ three ½” NPSM & three ½” drill-outs
-BB4, with three ½” drill-outs & one ½” open port
Weather Tight -EU, -EUO, w/ two ½” knockouts
Enclosure Ratings
J-Box -JB, NEMA 1
No Box -NB, No rating
Weatherproof -WP, NEMA 3R, IP14
BAPI-Box -BB, NEMA 4X, IP66
BAPI-Box 2 -BB2, NEMA 4X, IP66
BAPI-Box 4: -BB4, IP10
(IP44 with Knockout Plug in open port)
Weather Tight -EU, IP44
Weather Tight -EUO, NEMA 4X, IP66, UV rated
Enclosure Materials
J-Box -JB, Galvanized steel, UL94H-B
No Box -NB, Nylon 66, UL94H-B
Weather Proof -WP, Cast Aluminum, UV rated
BAPI-Box -BB, Polycarbonate, UL94V-0, UV rated
BAPI-Box 2 -BB2, Polycarbonate, UL94V-0, UV rated
BAPI-Box 4: -BB4, Polycarbonate & Nylon, UL94V-0
Weather Tight -EU, ABS Plastic, UL94V-0
Weather Tight -EUO, ABS Plastic, UL94V-0, UV rated
Ambient (Encl.) 0 to 100% RH, Non-condensing
All BAPI-Boxes -BB, BB2, BB4, -40 to 185ºF, (-40 to 85ºC)
Weather Tight -EUO, EU, -40 to 185ºF, (-40 to 85ºC)
J-Box & No Box -JB, NB, -40 to 212ºF, (-40 to 100ºC)
Weatherproof -WP, -40ºF to 212ºF, (-40º to 100ºC)
Agency RoHS, *CE
PT= DIN43760, IEC Pub 751-1983,
JIS C1604-1989
*Passive Thermistors 20KΩ and smaller
are CE compliant
Specications subject to change without notice.
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