Top 10 errors in greenhouse wiring

Based on inspection reports and NEN 1010/3140 audits in Dutch greenhouses.

1. IP class too low — IP44 in zones where IP55 or higher is required (§740).
2. 30 mA RCD not installed on mobile equipment handled by staff.
3. N-conductor shared between RCD groups — RCD trips randomly, people bypass it.
4. HF interference from lighting fixtures blinds RCD type A — type F or B required.
5. Unprotected cables through walkways — no mechanical protection, requirement §740.
6. Main equipotential bonding missing on CO₂ pipes — danger in case of insulation fault.
7. Pt1000 sensors in 2-wire connection — measurement drift, poor climate control.
8. No logbook for installations / work equipment — NEN 3140 mandatory.
9. Extension cords longer than allowed without voltage drop calculation.
10. Unauthorized switching under load — no VOP/VP indication, Arbowet violation.

See also: NEN 1010 §740 Horticulture and NEN 3140 VP.