The ULAMEX Earthing Rod Ø16 is a hot-dip galvanised steel ground electrode conforming to EN ISO 1461, designed as the primary earth connection point for photovoltaic installations and lightning protection systems. Supplied as a two-piece set (2 × 1500 mm) for a total driven depth of 3 metres, the rod is driven vertically into the soil to establish a low-resistance path to earth — the foundational element of every grounding and equipotential bonding system per IEC 62305 (lightning protection) and IEC 62548 (PV array safety).
Technical Specifications
| Parameter | Value |
|---|---|
| Material | Steel, hot-dip galvanised (EN ISO 1461) |
| Diameter | Ø 16 mm |
| Length | 2 × 1500 mm (two-piece, 3000 mm total) |
| Joining method | Threaded coupling or driving coupler between sections |
| Point type | Forged driving point (hardened tip) |
| Galvanisation | Hot-dip zinc coating ≥ 55 µm per EN ISO 1461 |
| Standards | IEC 62305 (lightning protection), IEC 62561 (lightning protection components), IEC 62548 (PV arrays) |
| Target earth resistance | < 10 Ω (per IEC 62305-3) |
Installation Guidelines
Select the installation location close to the PV array or building lightning protection down-conductor, in an area with soil suitable for driving (avoid rocky ground, concrete foundations, or heavily compacted sub-base). The rod should be positioned where the earthing conductor from the PV mounting system can reach with a short, direct cable run.
Begin with the first 1500 mm section. Place the forged driving point downward and drive the rod vertically into the soil using a manual sledgehammer or electric driving hammer (SDS-max) with a rod driving adapter. Drive the first section until approximately 50–100 mm remains above ground level. Thread or couple the second 1500 mm section onto the exposed end of the first section, and continue driving until the top of the second section is approximately 300–500 mm below finished ground level — or flush with the inspection pit if one is provided.
After driving, measure the earth resistance using a ground resistance tester (fall-of-potential method or stakeless clamp method). The target is < 10 Ω per IEC 62305-3 for lightning protection systems. If the measured resistance exceeds 10 Ω, the soil resistivity is too high for a single 3 m rod — options include: driving a longer rod (add a third section), installing a second rod at ≥ 3 m distance and connecting in parallel, or treating the surrounding soil with bentonite or conductive backfill to reduce resistivity.
Applications
- PV system grounding — primary earth electrode for the photovoltaic installation, connecting the mounting system’s equipotential bonding network to earth via grounding plates and earthing conductors
- Lightning protection systems (LPS) — earth termination network for external lightning protection per IEC 62305-3, connecting down-conductors to the soil
- Ground-mount solar farms — distributed earthing network with multiple rods at regular intervals along the post structure
- Building main earthing — supplementary earth electrode for the building’s main earthing terminal (MET) when the existing earthing system is inadequate for the added PV load
- Temporary construction earthing — site earth electrode during PV array construction and commissioning phases
Material Properties
Hot-dip galvanisation per EN ISO 1461 provides a minimum 55 µm zinc coating on the steel rod surface, protecting against soil corrosion for the service life of the installation. In normal soils (pH 5–9, resistivity > 50 Ω·m), the zinc coating is consumed at approximately 1–2 µm per year, giving a theoretical coating life of 30–55 years before the base steel is exposed. This exceeds the typical 25–30 year PV system design life.
In aggressive soils (high acidity pH < 5, high salinity, waterlogged clay, or resistivity < 25 Ω·m), the zinc consumption rate increases significantly. For such conditions, copper-bonded or solid copper earthing rods may be preferable. The hot-dip galvanised rod is the standard cost-effective solution for the vast majority of European soil conditions encountered in residential and commercial PV installations.
The Ø16 mm diameter provides the mechanical stiffness required for driving to 3 m depth without rod bending or buckling, while maintaining the minimum cross-sectional area required by IEC 62561-2 for earthing rod components in lightning protection systems.
Compatibility
The ULAMEX earthing rod is used with:
- ULAMEX earthing rod connectors (product 469) — cross clamp connectors for attaching the earthing conductor to the rod head
- Earthing conductors Cu 10 mm² / 16 mm² — connecting the rod to the PV mounting system’s equipotential bonding network
- ULAMEX grounding plates (product 449) — at the other end of the earthing conductor, connecting to the aluminium PV rails
- PV mounting rails — indirectly, via the grounding plate → earthing conductor → earthing rod chain
- Lightning protection down-conductors — connecting the LPS air termination network to earth
Why ULAMEX
ULAMEX is an EN 1090 certified B2B wholesaler supplying the complete PV grounding and earthing system — earthing rods, rod connectors (product 469), grounding plates (product 449), and all associated mounting profiles and fasteners. The full earthing chain from rail to soil is available from a single source — one order, one delivery, one invoice. Stocked for immediate dispatch with pallet delivery across Europe.
Frequently Asked Questions
Q: Why is the rod supplied in two pieces instead of one 3 m length?
A single 3 m rod is impractical to transport, handle, and drive — the starting height for driving would require a ladder or elevated platform. The two-piece design (2 × 1500 mm) allows the first section to be driven to near ground level from a standing position, then the second section is coupled on and driven from the same position. This is standard practice for earthing rods worldwide.
Q: How do I know if my soil has acceptable resistivity?
Measure with a ground resistance tester after driving the rod. If the measured earth resistance is below 10 Ω, the soil is adequate. Typical values: moist clay = 2–5 Ω (excellent), sandy loam = 5–15 Ω (adequate to marginal), dry sand or gravel = 20–100+ Ω (inadequate, additional rods or treatment needed). Soil resistivity varies seasonally — measure in the driest expected conditions for a worst-case result.
Q: What is the minimum driving depth?
IEC 62305-3 recommends a minimum driving depth of 2.5 m for vertical earthing rods. The ULAMEX two-piece set provides 3 m total length, exceeding this minimum. The rod should be driven until the top is below the frost line (typically 0.8–1.2 m in Central Europe) to avoid resistance increase from frozen soil in winter.
Q: Can I use this rod with copper earthing conductors?
Yes, but use a bimetallic transition connector or a galvanised clamp at the copper-to-galvanised-steel junction to manage the galvanic potential difference. Direct copper-to-galvanised-steel contact in soil accelerates zinc coating consumption. ULAMEX earthing rod connectors (product 469) are designed for this transition.
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