Sizes the cable, breaker and RCD protection for a single EV charge point per IEC 61851-1/60364-7-722/62955, with guidance on earthing-arrangement compatibility and the correct RCD type \u2014 plus advanced multi-point site demand aggregation with Load Management System diversity.
Standards followed
IEC 61851-1 (electric vehicle conductive charging system — charging modes)IEC 60364-7-722 (electrical installations — supplies for electric vehicles)IEC 62955 (residual direct current detecting devices, RDC-DD)
What it can do
- Charging-mode guidance (Mode 1-4) with mode-specific notes and scope warnings.
- Cable sizing to a single charge point (ampacity + voltage drop) and recommended breaker from standard sizes.
- Earthing-arrangement guidance including the TN-C-S/PME PEN-conductor warning for the final circuit.
- RCD protection guidance (Type B vs. Type A/F + RDC-DD per IEC 62955).
- Advanced: multi charge point site design — raw vs. diversified design current (IEC 60364-7-722.311 diversity rules, with or without an LMS) and recommended feeder cable size.
Example problem
A Mode 3, 32A, single-phase charge point, copper conductors, XLPE90 insulation, installation method C, 25m route length.
- Design current = EVSE rated current directly = 32A (unlike most loads, no power/PF derivation needed).
- Size the cable to satisfy both method-C ampacity at 32A and the 5% voltage-drop limit over 25m.
- Select the standard breaker size that protects the chosen cable.
4mm² cable at 2.03% voltage drop (within the 5% limit) with a 32A breaker. The default 10-point multi-site scenario (no LMS, diversity = 1) sizes the feeder to 120mm² at 1.06% voltage drop for 320A.
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