Mobile-first trade tool with presets, quick steppers, installation-origin voltage drop handling and 70°C / 90°C terminal logic.
Quick presets
Tap once to auto-fill a common setup.
Large step buttons for quick on-site adjustment.
Advanced optionsOpen / close
Recommended cable size
6mm² Twin & Earth
✔ Looks suitable
Design current
32.0A
Adjusted current
35.6A
Circuit voltage drop
4.0V
Circuit voltage drop %
1.7%
Upstream drop used
0.0%
Drop remaining
5.0%
Total installation drop
1.7%
Capacity pass
Circuit drop pass
Installation drop pass
Good headroom
Capacity use76%
Circuit drop use34%
Breaker use68%
Max distance
40.8m
Practical amps
47A
Approx kW
8.6kW
Result copied.
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Comparison
Nearby sizes, estimated cost and quick verdict.
Size
Capacity
Circuit drop %
Total drop %
Cost
Verdict
Guidance note:
This pro tool is designed as a practical cable sizing aid using BS 7671-style thinking, including 70°C / 90°C terminal assumptions and origin-to-circuit voltage drop handling. It does not replace full design verification, product data, inspection, testing or qualified professional judgement.
