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Voltage Drop

Check voltage drop using the mV/A/m method with cable data from BS 7671 tables.

Phase

Supply voltage

Max allowable drop

Design current (Ib)

One-way length

Cable mV/A/m

mV/A/m

From manufacturer data or BS 7671 tables

Cable preset (BS 7671 abridged)

Single-phase (2-core) values; auto-scaled ×0.866 when 3φ. Verify against actual cable data.

Enter current, length, and mV/A/m to calculate