Industries
Industries
- General Industrial
- Aerospace
- Brick & Ceramics
- Chemical & Petrochemical
- Pharmaceutical, Food, Dairy, & Beverage
- Engineering & Architecture (EPC Firms) & Major Equipment OEMs
- Glass
- Incineration
- Metals Manufacturing & Heat Treating
- OEM & Equipment Builders
- Oil & Gas - Downstream & Refining
- Oil & Gas Upstream and Midstream
- Plastics & Fiber / Textiles Industries
- Power
- Pulp & Paper
- Rubber, Cement, & Aggregate
- Semiconductor
- Test & Measurement
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Frequently Bought Together
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RTDs
RTDs (Resistance Temperature Detectors) rely upon resistance to indicate temperature. RTD sensors in this section are most frequently constructed of platinum 100 Ω resistance elements (PT100) and a resistance temperature curve (alpha or α) of .00385 Ω/ Ω/°C (3.851 x 10-3°C-1) although other resistance elements are readily available. PT100s are named for having a resistance of 100 Ω at 0°C.
RTDs are extremely accurate and repeatable at temperatures up to about 500°C (900°F). Although RTDs are readily available with higher temperature ratings at that point their advantages versus a thermocouple start to diminish.
RTDs do not require specially compensated lead wire. Industrial applications most commonly call for three wire construction. For best accuracy, however, select four wire constructions to avoid the potential for errors due to lead wire resistance.
Want to configure an RTD with a matching thermowell or protection tube? Click here to select and configure your assembly type!
| Organization | Standard | Alpha | Nominal Resistance(ohms) At 0°C |
|---|---|---|---|
| International Electrotechnical Commission (Supersedes BS & DIN) |
IEC 60751: 2022 | 0.00385 |
100 |
| ASTM International | ASTM E1137/E1137M-08 (2020) | 0.00385 | 100 |
| American Scientific Apparatus Makers Association (SAMA) |
RC21-4-1966 | 0.003923 | 98.129 |
| British Standards Association |
b.S. 1904-1964 | 0.00385 | 100 |
| Normenstelle Elektrotechnik |
DIN 43760 | 0.00385 | 100 |
| US Department of Defense |
MIL-T-24388 | 0.00392 | 100 |
Tolerance Classes for Wound Resistors
| Tolerance Class | Tolerance Value (°C) | Temperature Range of Validity of Tolerances |
|---|---|---|
| W 0.1 | ±(0.1° + 0.0017[t]) | -50° to 250° |
| W 0.15 | ±(0.15° + 0.002[t]) | -100° to 450° |
| W 0.3 | ±(0.3° + 0.005[t]) | -196° to 661° |
| W 0.6 | ±(0.6° + 0.01[t]) | -196° to 661° |
Tolerance Classes for Film Resistors
| Tolerance Class | Tolerance Value (°C) | Temperature Range of Validity of Tolerances |
|---|---|---|
| F 0.1 | ±(0.1° + 0.0017[t]) | -50° to 250° |
| F 0.15 | ±(0.15° + 0.002[t]) | -50° to 450° |
| F 0.3 | ±(0.3° + 0.005[t]) | -50° to 661° |
| F 0.6 | ±(0.6° + 0.01[t]) | -50° to 661° |
Tolerance Classes for Thermometers (Finished Probes)
| Tolerance Class | Tolerance Value (°C) | Temperature Range of Validity of Tolerances |
|---|---|---|
| AA | ±(0.1° + 0.0017[t]) | -50° to 250° |
| A | ±(0.13° + 0.0017[t]) | -100° to 450° |
| B | ±(0.25° + 0.0042[t]) | -196° to 600° |
| C | ±(0.6° + 0.01[t]) | -196° to 600° |
Resources
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