TN-C-S or TT?
If the input line has PEN (4-wire) — make TN-C-S: split PEN into N and PE at the input, re-ground it. If re-grounding is not possible (bad soil) — TT with your own loop and RCD 300 mA.
Loop construction
3-6 vertical electrodes 2.5-3 m at a distance of 3 m, connected with a horizontal strip 4×40 mm. Depth of the top of the electrodes — 0.5 m below the surface.
Resistance norm
≤ 4 Ω for TN (per PUE) or ≤ 30 Ω for TT with RCD (per IEC 60364). Measure with a tester, not a multimeter.
Connection
The main ground bus (GZSh) in the panel, PE to it, N — separately through the meter. Never swap N and PE after the split.
Checks
Continuity of PE, resistance, RCD trip test. The protocol is part of the acceptance documentation.
GorkyCAD
Counts the loop: soil, electrodes, resistance check — the grounding drawing goes to the plan.
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