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Temperature Sensors
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They may not be reproduced, published, or transmitted electronically for commercial purposes.
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Overview
TE – Temperature Sensor
BTT – Temperature Transmitters
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TE - Introduction
Duct and immersion temperature sensor
Uses a thermistor or RTD for temperature
sensing
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TE - Key Specifications
Accuracy:
Thermistor temperature sensor: ±0.2°C @ 25°C (±0.36°F @
77°F);
RTD temperature sensor: DIN class A: ±0.15°C @ 0°C
(±0.28°F @ 32°F).
Temperature Limits: Operating: -40 to 302°F (-40 to
150°C)
Housing Material: Meets UL, 94 V-O polycarbonate
plastic
Housing Rating: NEMA 4X (IP66) (DFW, IBW only)
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TE - Technology
Thermistor
Type of resistor whose resistance varies significantly
with temperature
Material is typically a ceramic or polymer
Compared to RTDs, which use pure metals
Two types:
NTC (negative thermal coefficient) – resistance decreases
with increasing temperature
PTC (positive thermal coefficient) – resistance increases
with increasing temperature
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TE - Technology
RTD
Consist of a fine coiled wire wrapped around a glass
or ceramic core
Typically made of pure material such as platinum,
nickel or copper
Material has a very predictable change in resistance
in response to temperature
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TE – RTDs vs.
Thermocouples
RTD/Thermistors:
Very high accuracy and repeatability
Can maintain stability for many years, while thermocouples
can drift within the first few hours of use
Thermocouples:
More suitable for temperatures above 600° C
Faster response time (fractions of a second vs. seconds)
Can be much smaller than RTDs and thermistors
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TE - Applications
Used to monitor air or water temperature
throughout a building management system or an
air handler unit
Immersion sensors which are supplied with
compression fittings are typically used to
monitor the hot or chilled water lines
throughout a building
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BTT - Introduction
Includes duct, immersion, and outside air
mounting configurations
Outside air models can be ordered with or
without a radiation shield
Stainless steel thermowells are available for
immersion models
Uses a Pt1000 RTD temperature sensor
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BTT - Key Specifications
Wetted Material: 304 SS, polycarbonate, and neoprene (nylon
and silicone for outside air models)
Enclosure Rating: NEMA 4X (IP66)
Probe Length: 2.5 to 18 inches (63.5 to 457mm)
Temperature Limits: 32 to 122°F (0 to 50°C)
Response Time: 100 msec
Agency Approvals: CE
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BTT - Applications
Monitoring the temperature inside air ducts for
HVAC
Transmitting temperature inside water lines for
chillers
Measuring the outside air temperature of any
new or existing facility
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