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🔧 Resistor Series & Parallel Calculator

Calculate total resistance with error propagation using both RSS (statistical) and worst-case methods.

Resistor Values

Resistor 1

Resistor 2

📊 RSS Method (Independent Errors)

Series Combination

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Parallel Combination

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⚠️ Worst-Case Method (Maximum Error)

Series Combination (Worst-Case)

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Parallel Combination (Worst-Case)

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Methodology

Series: Rtotal = R₁ + R₂

Parallel: Rtotal = (R₁ × R₂)/(R₁ + R₂)

Error Propagation Methods

RSS (Root Sum Square): Assumes errors are independent and random.
Δf = √(Σ(∂f/∂xᵢ · Δxᵢ)²)

Worst-Case: Assumes all errors add in the same direction (most conservative).
Δf = Σ|∂f/∂xᵢ · Δxᵢ|

Use RSS for typical production tolerances. Use worst-case for critical designs.