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R1+R2 Calculator

Work out R1+R2 from measured Zs and Ze. Useful for checking notes before filling out certificates.

Estimator only. Confirm measured values and testing method before recording results.

Notes and next steps

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How it works

Calculate R1+R2 from measured Zs and Ze.

Formula used: R1+R2 = Zs − Ze.

Worked example

Measured Zs 0.77 Ω minus Ze 0.35 Ω gives R1+R2 of 0.42 Ω.

Common mistakes
  • Mixing measured and estimated values.
  • Forgetting parallel paths can affect readings.
  • Recording rounded values without checking context.
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