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Affordable working standard SPRT
- Range to aluminum point (660 °C )
- Inconel™ and platinum sheaths guard against contamination
- Less than 8 mK/year drift
- Many calibration options available including by fixed point
- Fifth wire provides shield ground
SPRTs designed by Fluke Calibration are known for their outstanding reliability and minimal long-term drift. They have been calibrated by national (and other primary) laboratories and proven repeatedly to outperform competitive models. Now Fluke Calibration’s 5699 Extended Range Metal-Sheath SPRT combines all the advantages of a Fluke Calibration-designed sensor with the protective sheathing materials that allow your SPRT to be used in virtually any furnace or bath with temperatures as high as 670 °C.
Designed and manufactured by our primary standards metrologists, the strain-free sensing element in the 5699 meets all ITS-90 requirements for SPRTs and minimizes long-term drift.
After one year of regular usage, drift is less than 0.008 °C (< 0.003 °C is typical). Even lower drift rates are possible depending on care and handling. A fifth wire for grounding is added to the four-wire sensor to help reduce electrical noise, particularly for AC measurements. Finally, you can get an improved version of an old industry-standard Inconel-sheathed SPRT.
The 5699 is constructed with a 0.219-inch-diameter Inconel sheath for high durability and fast response times. Inside the sheath, the sensing element is protected by a thin platinum housing that shields the sensor from contamination from free-floating metal ions found within metal environments at high temperatures. Reduced contamination means a low drift rate—even after hours of use in metal-block furnaces at high temperatures.
If you choose not to calibrate the 5699 yourself, a wide variety of options are available from Fluke Calibration’s own primary standards laboratory, including fixed-point calibrations covering any range between –200 °C and 661 °C.
At Fluke Calibration, we use SPRTs every day. We design them, build them, calibrate them, use them as standards, and know what it takes to make a reliably performing instrument. Why buy from anyone else?
Specifications | |
Temperature Range | –200 °C to 661 °C (recommended annealing temperature 665 °C) |
Nominal RTPW | 25.5Ω (± 0.5Ω) |
Current | 1 mA |
Resistance Ratio | W(302.9146 K) ≥ 1.11807 W(234.3156 K) ≤ 0.844235 |
Sensitivity | 0.1 Ω/ °C |
Drift Rate | < 0.008 °C/year (< 0.003 °C/year typical) |
Repeatability | < 1 mK |
Self-heating at TPW | < 0.001 °C under 1 mA current |
Reproducibility | ± 0.001 °C or better |
RTPW Drift After Thermal Cycling | < 0.001 °C |
Diameter of Pt Sensor Wire | 0.07 mm (0.003 in) |
Lead Wires | Four sensor wires plus grounding wire |
Protective Sheath | Inconel |
Diameter: | 5.56 mm ± 0.13 mm (0.219 in ± 0.005 in) |
Length: | 482 mm (19 in) |
Insulation Resistance | > 100 MΩ at 661 °C > 1000 MΩ at 20 °C |
Model Name | Description |
---|---|
5699-S |
Extended Range Metal-Sheath SPRT with Maple carrying case |
Accessories common to all models:
Accessory | Description |
---|---|
1911-4-7 |
PRT Calibration, –200 °C to 660 °C, NVLAP Accredited |
Product Manuals |
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On-Demand Webinars |
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Overcoming Drift: Tips to Maintaining Your PRTs |
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