Series-BTT

Supported Applications

The Dwyer Series BTT Temperature Transmitter is designed for monitoring temperature in HVAC ducts, water lines for chillers, and outside air for new or existing facilities. The series supports duct, immersion, and outside air mounting configurations to accommodate these environments.

• HVAC duct applications
• Water line monitoring for chillers (immersion models require thermowells)
• Outside air temperature measurement with optional radiation shields for direct sunlight exposure

Operating Conditions & Performance

The Series BTT utilizes a Pt1000 RTD sensor to deliver an accuracy of ±0.5°C @ 25°C across its documented ranges. Measurement capabilities vary by model configuration, offering ranges from -40 to 140°F (-40 to 60°C) and 32 to 212°F (0 to 100°C). The transmitter features a response time of 100 msec.

• Process Temperature: -40 to 140°F (-40 to 60°C) or 32 to 212°F (0 to 100°C) depending on model
• Ambient Temperature Limits: -40 to 140°F (-40 to 60°C)
• Enclosure Rating: NEMA 4X (IP66) for duct, immersion, and outside air models; IP20 for wall-mount variants

Wetted Materials & Construction

All probe configurations utilize a 304 SS sheath. The housing is constructed from polycarbonate. Duct and immersion models incorporate Neoprene gaskets, while outside air models use Nylon inserts with silicone O-rings.

• Probe: 304 SS
• Housing: Polycarbonate
• Gasket (Duct/Immersion): Neoprene
• O-ring (Outside Air): Silicone; Insert: Nylon

Configuration Options

The series offers configurable mounting styles, probe lengths, output signals, and calibration options to meet specific installation requirements.

Mounting Configurations & Probe Lengths

• Duct mount (D)
• Immersion mount (I) with 1/2" NPS process connection; actual probe length is approximately 0.75" longer than listed to ensure maximum immersion into thermowells.
• Outside air (O)
• Outside air with radiation shield (R); requires a 2.5" probe length

Duct and immersion models are available in probe lengths of 4", 6", 8", 12", and 18".

Outputs & Power Requirements

• Output Signals: 4-20 mA or 0-10 VDC (depending on model)
• Power Supply: 13-36 VDC for current models; 13-36 VDC or 16-28 VAC for voltage models

Housing & Electrical Connections

Duct, immersion, and outside air units feature a removable terminal block with PG11 and PG16 knockouts. Wall-mount variants (BTT-E/N) utilize screw terminal blocks.

Key Product Differences

The Series BTT encompasses two distinct form factors: field-mounted transmitters for ducts, liquids, and outside air; and wall-mounted room sensors.

• Duct/Immersion/Outside Air Models: Designed with 304 SS probes of varying lengths (2.5" to 18"). These units carry a NEMA 4X (IP66) rating, though immersion models require thermowells for liquid applications.
• Wall Mount Models (BTT-E/N): Designed for room or indoor building space monitoring with North American Style and European Style housings. These variants feature an IP20 enclosure rating and a measurement range of 32 to 122°F (0 to 50°C).

Calibration options include Factory calibration certificate (FC) and NIST calibration certificate (NIST). The series provides form and fit compatibility with popular TE thermistor and RTD sensors.