Reference Probes - Hart Scientific Secondary Standards PRT's Models 5626 and 5628

Hart’s SPRT design team is introducing two new hi-temp Secondary Standards that fill the gap between affordable but temperature-limited secondary PRTs and more expensive, highly accurate SPRTs.

If you’re using block calibrators, furnaces, or temperature points above normal secondary RTD temperatures (500°C), then these two PRTs are for you. The 5626 is nominally 100W and the 5628 is nominally 25.5W. Both instruments have a temperature range of –200°C to 660°C. They make great working or check standards for calibration work up to the Aluminum 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. The 5626 and 5628 are designed to reduce the contamination risk through the use of internal protection while not impairing performance.