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MCB / Fuse Size Calculator
Enter the connected load to get a recommended circuit breaker rating.
- Full-load current
- 13.0 A
- Recommended MCB
- 20 A
Use a Curve-B or Curve-C MCB for lighting and general resistive loads. Motors, pumps and other high-inrush loads usually need Curve-C or Curve-D to avoid nuisance tripping.
This tool gives a quick estimate for planning purposes only — it doesn't account for every site condition (ambient temperature, conduit fill, local code). For a final specification or anything connected to your mains, have it checked by a licensed electrician — talk to us.