Field Measurements
Unnamed Project · IEC 60364-4-41 · TN-S · Uo 230 V
BS 7671 Appendix 3 & IEC 60364-6 apply a 0.8× ambient-to-operating temperature factor (Zs_max_site = 0.8 × 0.95 × Uo / Im) plus IEC 60364-5-54 adiabatic PE thermal check. How to calculate Zs & PE (IEC 60364)
Standard Limits, Equations & Space Presets
IEC 60364-4-41 / BS 7671 Maximum Loop Impedance Zs tables for MCBs (Type B/C/D) and fuses, Cmin = 0.95 voltage factor, 0.8x ambient temperature correction, and IEC 60364-5-54 adiabatic PE conductor k factors.
One-Click Normative Presets (Auto-fills Target Limits)
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Direct MFT import supported: Fluke TruTest / DMS · Megger CertSuite / MFT-X1 · Metrel EuroLink PRO · Chauvin Arnoux · Excel CSV