Description
margin = rating-measured; fraction = measured/rating; exceeded uses measured > rating.
Electrical dissipation and temperature coefficients depend on operating conditions and component reference values. A calculated loss, local temperature factor or supplied-rating margin is only part of a thermal and reliability assessment.
margin = rating-measured; fraction = measured/rating; exceeded uses measured > rating.
When to use this tool
Use Resistor Power Rating Explicit Margin when checking one supplied loss, temperature or power-margin term.
How to use the tool and how it works
- Enter measured, rating. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read margin, fraction, exceeded. Inspect exceeded before interpreting the associated values.
Require nonnegative measured power and positive rating. margin = rating-measured; fraction = measured/rating; exceeded uses measured > rating.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| measured | Measured | Required. Finite number; minimum 0. |
| rating | Rating | Required. Finite number; strictly above 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| margin | Margin | Required. Finite number. |
| fraction | Dimensionless fraction on the stated denominator basis, not multiplied by 100. | Required. Finite number. |
| exceeded | Exceeded | Required. Boolean. |
{
"input": {
"measured": 3,
"rating": 4
},
"output": {
"margin": 1,
"fraction": 0.75,
"exceeded": false
}
}Limitations and assumptions
- Use matching power units. Equality is not exceeded in this arithmetic; practical derating, cooling, transients and manufacturer restrictions are not assessed.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.
Alternative or Complementary methods
Use manufacturer ratings, thermal paths, derating and transient conditions for a complete practical design.
References
Similar or alternative tools
- Capacitor Leakage Power Fraction
leakagePower = voltage²/leakageResistance; fraction = leakagePower/totalPower.
- Zener Series Resistor Power Term Tool
Calculate zener series resistor power term from explicit caller-supplied inputs.