5628-12-D

5628-12-D is a secondary standard PRT. If the user uses block calibrators, furnaces, or temperature points above normal PRT temperatures (420°C), then these two PRTs are for the user. The Fluke 5628 (formerly Hart Scientific) is nominally 25.5ohm. This makes great working or check standards for calibration work up to the aluminium point. Using a regular PRT at temperatures above 500°C exposes the platinum to contamination. If the PRT is used as a reference or calibration standard, contamination is a major problem. SPRTs, which are more expensive and delicate, can handle the higher temperatures, but with greater risk to the instrument due to shock, contamination, or mishandling. It is designed to reduce the contamination risk through the use of internal protection while not impairing performance. In addition to the right measurement performance and durability, a PRT for secondary applications should be priced affordably.

• Meets all ITS-90 requirements for resistance ratios
• Rtp drift <lt/> 20mK after 500 hours at 661°C, calibrated accuracy of ±0.006°C at 0°C
• W(302.9146K) ≥ 1.11807 α ≥ 0.003925 resistance ratio W(Ga)
• Stability is ±0.002°C, long-term drift (k=2) is <lt/>0.004°C/100 hours at 661°C
• Immersion at least 12.7cm recommended, Inconel™ 600 sheath
• 4-wire Super-Flex PVC, 22 AGW lead wires, gold-plated spade lugs, or specify termination
• 5-pin DIN for tweener thermometers, temperature range from -200°C to 661°C