Convert Degree Fahrenheit per watt to Hour-degree Celsius per kilocalorie

Convert Degree Fahrenheit per watt (°F/W) to Hour-degree Celsius per kilocalorie (h·°C/kcal) instantly and accurately.

Degree Fahrenheit per watt (°F/W)
Hour-degree Celsius per kilocalorie (h·°C/kcal)

Conversion Formula

h·°C/kcal = °F/W × 0.6461111111

About Degree Fahrenheit per watt

The degree Fahrenheit per watt (°F/W) equals exactly 5/9 K/W ≈ 0.5556 K/W. It appears in US power electronics datasheets and legacy JEDEC thermal specifications where junction-to-case resistance is reported in °F/W rather than °C/W or K/W. A device rated 5 °F/W has R = 5 × 5/9 ≈ 2.78 K/W. 1 °F/W = 5/9 K/W.

About Hour-degree Celsius per kilocalorie

The h·°C/kcal equals 3600/4186.8 K/W ≈ 0.8598 K/W. Used in pre-SI European engineering literature (French, German, Italian) for heat transfer system calculations. A boiler with 1 h·°C/kcal resistance passes 1 kcal/h per °C temperature difference. Superseded by K/W and h·°C/W in modern standards. 1 h·°C/kcal ≈ 0.8598 K/W.

Quick Reference Table

Degree Fahrenheit per watt (°F/W)Hour-degree Celsius per kilocalorie (h·°C/kcal)
1 °F/W0.646111 h·°C/kcal
2 °F/W1.29222 h·°C/kcal
5 °F/W3.23056 h·°C/kcal
10 °F/W6.46111 h·°C/kcal
25 °F/W16.1528 h·°C/kcal
50 °F/W32.3056 h·°C/kcal
100 °F/W64.6111 h·°C/kcal

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