RTDs (Resistance Temperature Detectors)

Resistance Temperature Detectors (RTDs) are precision temperature sensors designed to deliver accurate, repeatable temperature measurement in industrial, commercial, and scientific applications. RSP Supply carries a broad selection of RTDs from trusted manufacturers, including ACI, Dwyer, and Omega. These sensors rely on the predictable relationship between temperature and electrical resistance, most commonly using platinum elements, to provide dependable performance over long service life.

RTDs are available with wire-wound or thin-film sensing elements to suit different application requirements. Wire-wound RTDs offer exceptional stability and accuracy across wide temperature ranges, making them well-suited for process control and calibration-critical environments. Thin-film RTDs provide a compact form factor ideal for space-constrained installations while still maintaining reliable accuracy. ACI, Dwyer, and Omega RTDs are offered in a variety of probe styles, housings, and mounting configurations to support diverse installation needs.

To minimize measurement error caused by lead wire resistance, RTDs are commonly configured using 3-wire or 4-wire connections. When combined with standardized calibration practices, RTDs deliver consistent and repeatable temperature data.

Found 413 items
Normally In Stock
ACI 124480 A/100-3W-PO-4"-EXPL Probe,3 Wire,100 Ohm RTD
Free U.S Ground shipping
$73.98
$61.65
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ACI 142483 A/1K-3W-PM 3 Wire,1K Ohm RTD
Free U.S Ground shipping
$37.26
$31.05
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ACI 144138 A/100-2W-R2 2 Wire,100 Ohm Room RTD
Free U.S Ground shipping
$36.18
$30.15
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ACI 125216 A/1K-3W-O-EH 3 Wire,1K Ohm Outside Air RTD
Free U.S Ground shipping
$64.80
$54.00
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ACI 124215 A/100-3W-I-2.5"-PB 3 Wire,100 Ohm Immersion RTD
Free U.S Ground shipping
$65.88
$54.90
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ACI 120048 A/100-3W-PO-4" Probe,3 Wire,100 Ohm RTD
Free U.S Ground shipping
$32.40
$27.00
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ACI 119995 A/100-3W-BP-20'-CL2P Bullet Probe,3 Wire,100 Ohm RTD
Free U.S Ground shipping
$64.26
$53.55
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ACI 139344 A/100-3W-O-SUN 3 Wire,100 Ohm Outside Air RTD
Free U.S Ground shipping
$351.54
$292.95
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ACI 144154 A/1K-2W-R 2 Wire,1K Ohm Room RTD
Free U.S Ground shipping
$36.18
$30.15
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ACI 126690 A/1K-2W-PO-6" Probe,2 Wire,1K Ohm RTD
Free U.S Ground shipping
$32.40
$27.00
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ACI 135506 A/100-3W-INW-2.5"-4X 3 Wire,100 Ohm Immersion RTD
Free U.S Ground shipping
$67.50
$56.25
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ACI 119962 A/100-2W-PO-2" Probe,2 Wire,100 Ohm RTD
Free U.S Ground shipping
$32.40
$27.00
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ACI 119965 A/100-2W-PO-6" Probe,2 Wire,100 Ohm RTD
Free U.S Ground shipping
$25.92
$21.60
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ACI 119937 A/100-2W-BP Bullet Probe,2 Wire,100 Ohm RTD
Free U.S Ground shipping
$31.86
$26.55
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ACI 119452 A/100-3W-D-12"-GD 3 Wire,100 Ohm Duct RTD
Free U.S Ground shipping
$36.72
$30.60
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ACI 120261 A/1K-2W-BBS 2 Wire,1K Ohm RTD
Free U.S Ground shipping
$77.76
$64.80
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ACI 120300 A/1K-2W-I-4"-BB 2 Wire,1K Ohm Immersion RTD
Free U.S Ground shipping
$79.38
$66.15
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ACI 120283 A/1K-2W-D-8"-PB 2 Wire,1K Ohm RTD
Free U.S Ground shipping
$36.18
$30.15
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ACI 119569 A/1K-3W-RA-18"-GD Probe,3 Wire,1K Ohm RTD
Free U.S Ground shipping
$206.28
$171.90
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ACI 124200 A/1K-2W-I-4"-PB 2 Wire,1K Ohm Immersion RTD
Free U.S Ground shipping
$67.50
$56.25
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ACI 134714 A/1K-2W-O-SUN 2 Wire,1K Ohm Outside Air RTD
Free U.S Ground shipping
$360.18
$300.15
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ACI 147310 A/1K-2W-R2S-A10-C5 2 Wire,1K Ohm Room RTD
Free U.S Ground shipping
$49.14
$40.95
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ACI 147311 A/1K-2W-RS-RJ6-A09-C5 2 Wire,1K Ohm Room RTD
Free U.S Ground shipping
$66.42
$55.35
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ACI 147312 A/1K-2W-RSO-RJ6-A09-C5 2 Wire,1K Ohm Room RTD
Free U.S Ground shipping
$78.84
$65.70
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ACI 147313 A/1K-2W-R2SO-A09-G5 2 Wire,1K Ohm Room RTD
Free U.S Ground shipping
$62.64
$52.20
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ACI 147610 A/100-2W-INW-6"-BB 2 Wire,100 Ohm Immersion RTD
Free U.S Ground shipping
$52.92
$44.10
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ACI 147719 A/1K-3W-PO-4"-20'CL2P-HS Probe RTD
Free U.S Ground shipping
$64.26
$53.55
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ACI 147720 A/100-3W-PO-4"-20'CL2P-HS Probe RTD
Free U.S Ground shipping
$61.56
$51.30
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ACI 147768 A/1K-3W-PO-4"-10'CL2P-HS Probe RTD
Free U.S Ground shipping
$47.52
$39.60
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ACI 147789 A/1K-2W-A-100'-4X Copper Averaging,2 Wire,1K Ohm RTD
Free U.S Ground shipping
$597.24
$497.70
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ACI 147888 A/1K-2W-RSO-A28-C5 RTD
Free U.S Ground shipping
$62.64
$52.20
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ACI 147894 A/1K-3W-A-8'-GD-NIST Copper Averaging RTD
Free U.S Ground shipping
$241.38
$201.15
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ACI 148002 A/1K-2W-R2O 2 Wire,1K Ohm Room RTD
Free U.S Ground shipping
$48.60
$40.50
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ACI 148081 A/1K-2W-R2SO-A03-C5 2 Wire,1K Ohm Room RTD
Free U.S Ground shipping
$62.64
$52.20
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ACI 148082 A/1K-2W-R2S-A03-C5 2 Wire,1K Ohm Room RTD
Free U.S Ground shipping
$49.14
$40.95
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ACI 148083 A/1K-2W-RS-A03-C5 2 Wire,1K Ohm Room RTD
Free U.S Ground shipping
$49.14
$40.95
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ACI 148084 A/1K-2W-RSO-A03-C5 2 Wire,1K Ohm Room RTD
Free U.S Ground shipping
$62.64
$52.20
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ACI 148088 A/1K-2W-IM-6"-BB 2 Wire,1K Ohm Immersion RTD
Free U.S Ground shipping
$100.44
$83.70
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ACI 148089 A/1K-2W-IM-6"-GD 2 Wire,1K Ohm Immersion RTD
Free U.S Ground shipping
$78.84
$65.70
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ACI 148090 A/1K-2W-R2SO-A28-G5 2 Wire,1K Ohm RTD
Free U.S Ground shipping
$64.80
$54.00
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ACI 148108 A/1K-3W-D-12"-BB Duct RTD
Free U.S Ground shipping
$49.68
$41.40
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ACI 148268 A/1K-2W-A-24’-PB-NIST Copper Averaging,2 Wire,1K Ohm RTD
Free U.S Ground shipping
$268.38
$223.65
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ACI 148269 A/1K-2W-INW-2.5”-PB-NIST Immersion RTD
Free U.S Ground shipping
$95.58
$79.65
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ACI 148339 A/1K-2W-RS-A09-C5 2 Wire,1K Ohm Room RTD
Free U.S Ground shipping
$49.14
$40.95
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ACI 148368 A/100-3W-INW-8"-4X 3 Wire,100 Ohm Immersion RTD
Free U.S Ground shipping
$67.50
$56.25
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ACI 148583 A/1K-3W-A-8'-4X-NIST Copper Averaging,3 Wire,1K Ohm RTD
Free U.S Ground shipping
$270.00
$225.00
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ACI 142484 A/100-3W-PM 3 Wire,100 Ohm RTD
Free U.S Ground shipping
$36.72
$30.60
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ACI 142485 A/1K-3W-O-BB 3 Wire,1K Ohm Outside Air RTD
Free U.S Ground shipping
$64.80
$54.00

FAQs

Q: What is an RTD and how does it work?
An RTD (Resistance Temperature Detector) is a temperature sensor that measures temperature by detecting changes in electrical resistance as the sensing element’s temperature changes. Most RTDs use platinum elements, such as PT100 or PT1000, due to their stability and repeatability.

Q: What are the advantages of RTDs compared to thermocouples?
RTDs provide higher accuracy, better long-term stability, and superior repeatability than most thermocouples. They are ideal for applications where precise temperature measurement is more important than extreme temperature range.

Q: What industries commonly use RTDs?
RTDs are widely used in manufacturing, HVAC, pharmaceuticals, food and beverage processing, power generation, chemical processing, and laboratory environments.

Q: How accurate are RTDs?
RTDs typically offer accuracy ranging from ±0.05°C to ±0.3°C, depending on sensor class, configuration, and installation method. Using 3-wire or 4-wire configurations helps minimize lead resistance errors.

Q: Do RTDs require calibration and maintenance?
Yes, periodic calibration and inspection are recommended to maintain accuracy and detect potential drift or mechanical damage over time.

Why Buy Resistance Temperature Detectors from RSP Supply

RSP Supply offers a comprehensive selection of RTD temperature sensors designed for accurate and reliable measurement across a wide range of applications. Our inventory includes wire-wound and thin-film platinum RTDs suitable for industrial, scientific, and process control environments. Customers rely on RSP Supply for technical expertise, dependable sourcing, and temperature sensing solutions that support precise and consistent system performance.