Earthing & lightning protection · Buyer's guide
For a sectional ground-rod order, specify the actual rod diameter, coating, thread and compatible connection hardware together. Copper thickness and a test-standard name describe the product; resistance to earth also depends on the installation and soil. The catalogue examples below keep those two acceptance questions separate.
01
IEC 62561-2:2025 edition 3 covers conductors and metallic earth electrodes for lightning-protection systems. Its public preview shows the scope, references and test headings below, but not the numerical acceptance clauses. It also introduces an annex on applicability of previous tests; an older test report cannot simply be relabelled as a 2025 result [1].
nVent’s threaded-rod catalogue states a minimum 8 ft length for its UL 467 listed rods and a minimum 10 mil copper coating. Its 635840 row is 4 ft with IEC EN 62561-2 in the compliance column and no UL entry; 635880 is 8 ft and lists UL. These are manufacturer catalogue entries, not CNFX verification of an active UL listing or a quotation from UL 467 itself [2].
The current nVent resource list includes declarations or certificates citing IEC 62561-2:2018. The 2025 preview includes an annex about previous tests, whose acceptance details are not provided in the preview. Request the report, exact SKU and invoked edition; neither a newer catalogue date nor “IEC compliant” proves a full retest to 2025 [2] [1].
| Test in IEC 62561-2 (edition 3.0) | What it checks for a coated rod |
|---|---|
| Coating thickness | Thickness of the coating on earth rods; the standard references ISO 2178 magnetic measurement [1] |
| Adhesion | Adhesion test for copper-coated earth rods [1] |
| Bending | Bending test for copper-coated steel earth rods [1] |
| Environmental | Environmental test for coated rods; the standard references cyclic salt mist testing (IEC 60068-2-52) [1] |
| Electrical | Electrical resistance of coated rods and resistivity of earth rods [1] |
| Mechanical | Tensile strength and yield-to-tensile ratio for copper-coated steel rods [1] |
| Material and cross-section | Material, configuration and cross-sectional area; couplers are tested separately [1] |
02
The original three assembly groups below distinguish the electrode body, electrical connection and optional driving point. A sectional extension also needs its own coupler. This is a functional assembly reference, not a model manufacturing BOM.
| Component | Function | Material and compatibility evidence |
|---|---|---|
| Electrode rod | Places a conductive electrode in contact with the soil. | nVent’s threaded example has a steel core and electrolytic copper coating. TuAn separately names Q235 and 99.95% copper; that is a supplier claim, not the confirmed material of every copper-bonded rod [2] [3]. |
| Clamp / conductor connector | Joins the earthing conductor to the rod. | nVent Hammerlock is an irreversible copper connector with separate rod-diameter and conductor-size rows. It is not evidence that all clamps are bronze, brass or stainless, or that any 5/8-inch clamp fits any nominal 5/8-inch rod [4]. |
| Driving point, where specified | Helps drive a compatible threaded rod; it is separate from the conductor connection. | nVent’s driving-point range specifies steel and SDT58/SDT34 thread sizes. The related-product description limits it to internally threaded rods. Verify the rod-end configuration; a pointed rod may not need this separate part, and “hardened steel” was not established [6] [2]. |
For sectional rods, nVent’s CR58 coupler is bronze with 5/8-inch UNC threads and a nominal length of 2.4 inches. It joins rods; Hammerlock instead joins a conductor to a rod. Match drawings and product instructions rather than substituting one for the other [5] [4].
03
Catalogue names describe a nominal size, not the measured rod.
04
These are nVent catalogue examples, not specifications of TuAn or the other suppliers below. The manufacturer’s certifications column has not been independently checked in a listing registry [2].
| SKU | Actual diameter / length | Coating / thread | Catalogue certification entry |
|---|---|---|---|
| 635840 | 0.56 in / 4 ft | 10 mil / 5/8 in UNC | No UL entry |
| 635880 | 0.56 in / 8 ft | 10 mil / 5/8 in UNC | UL, RUS |
| 635883 | 0.56 in / 8 ft | 13 mil / 5/8 in UNC | UL, RUS |
| 634400 | 0.91 in / 10 ft | 10 mil / 1 in UNC | CSA-US, UL, cUL, CSA |
nVent’s EHL58C1V Hammerlock row pairs a 0.56-inch copper-bonded rod with #4–#2 stranded or 25 mm² stranded conductors. Its EHL58G1V galvanized-rod row instead uses a 0.63-inch actual diameter. The nominal 5/8-inch label is shared; the catalogue’s fit dimensions are not [4].
05
The bond between copper and steel is what stops the coating peeling when the rod is driven or bent.
The same Chinese product page describes a nano alkaline pre-plating (electrodeposition) process and, in its feature list, a cold-rolling and hot-drawing process creating a metallurgical bond [3]. Ask the supplier which process makes the rods you are buying and for the adhesion and bending test results to IEC 62561-2 [1].
The Chinese page claims a service life of more than 50 years [3]. Corrosion depends on soil; ask for environmental test results to the standard rather than a life figure.
06
Schneider Electric’s installation guide links resistance to installation and soil, with moisture, frost and ageing affecting the result. Agree site data, design and an installed-system measurement; a rod catalogue cannot promise the same resistance everywhere [7].
07
A quotation should identify the rod and hardware, then identify the installation tests separately. Unknown ratings below require the offered product’s evidence.
| Field | How to specify it |
|---|---|
| Rated current capacity | Define the duty, current waveform and relevant tested assembly. IEC’s preview separately lists a lightning-current test for couplers; that heading does not establish an arbitrary kA rating for every rod [1]. |
| Resistance to earth | Specify installed-system acceptance and test conditions. Soil and arrangement matter; do not present an ohm value as an unconditional rod property [7]. |
| Material grade | Name core and coating separately, plus connector and coupler materials. TuAn Q235/copper and nVent copper-bonded steel are different supplier descriptions [3] [2] [5]. |
| Diameter | Specify minimum actual diameter, nominal label and mating hardware. nVent 5/8-inch examples are 0.56-inch actual; its galvanized clamp examples need another actual fit size [2] [4]. |
| Length | Order a named SKU and section length, with total assembly depth separately. The catalogue’s UL entries are model-specific; actual installability needs site confirmation [2]. |
| Tensile strength | Request a minimum and test basis, not “up to” strength. nVent minimum 80,000 lbf/in² differs from TuAn’s 600 prose and 570 specification statements [2] [3]. |
| Corrosion resistance | Name coating minimum and environmental test evidence. A supplier’s >50-year claim is not a verified installed lifetime [3] [1]. |
| Operating temperature | Request limitations for the selected rod, joint and any ancillary equipment; the adopted rod sources do not establish a universal operating range. |
| Weight | Use the exact model’s unit weight and packaging. nVent635880 lists6.7lb; TuAnTGRCS142-2440 lists3.1kg. These are separate catalogue values, not an interchangeable item confirmation [2] [3]. |
| IP rating | No rod IP rating is established in the adopted sources. If the order includes an enclosure or monitoring device, request its own identified rating; do not attach an invented enclosure rating to bare metal. |
08
The linked Chinese records have different published supply scopes. Product listings establish an offer, not independent certification or the accuracy of every statement on a manufacturer page.
09
Ask for evidence tied to the rod size and length you order.
10
Paste it into your enquiry below or into an email to a maker, then replace every bracket.
Product: copper-bonded steel earth rod, quantity [pieces] Standard: [IEC 62561-2 edition __ / UL 467 / both] Size: nominal [5/8" / 3/4" / 14.2 mm / other], minimum actual diameter [mm]; length [m or ft] Copper: minimum thickness [µm or mil], purity [ ], bonding process [state] Ends: [pointed / threaded both ends / chamfered]; threads [rolled], thread size [ ] Accessories: couplers [n], driving heads [n], clamps or exothermic connections [ ] Soil: resistivity [Ω·m] or corrosive conditions [ ] Documents: test report (thickness, adhesion, bending, environmental), listing certificates, mill certificate for steel core Delivery to [country], target date [date]
See source-checked manufacturers Send an enquiry through CNFX
3 companies list this product among what they make. Company figures are quoted from each company's own website; every card states where the relationship came from.
the rod page offers copper-clad steel models, but the same page gives electrodeposition and cold-rolling/hot-drawing process descriptions, differing coating measures and 600 versus 570 N/mm² strength statements. Confirm the actual ordered model, minimum coating, bond process and report. No active certification listing or 50-year life was verified.
Product scope checked 2026-10-09
its Galvanized Ground Rod page offers zinc-coated carbon-steel rods, a different material route from the copper-bonded reference above. Its part table lists 12–20 mm while another specifications block states 14.2–25 mm; require the exact part drawing. No certificate was verified.
Product scope checked 2026-10-09
Publishes separate Ground Rod and Ground Rod Coupling pages. The rod table gives GR5/8 diameter 14.2 mm and coating 0.254 mm. The prose contains material/approval statements without test evidence; obtain a named model and test report.
Product scope checked 2026-10-09
Explore company information and manufacturing capabilities, then discuss the scope of your project with a relevant supplier.
Not necessarily: in one leading range the 5/8 in rod measures 0.56 in. Specify the actual diameter if a minimum is required. [2]
Rods listed to UL 467 in one range have at least 10 mil (0.254 mm) of copper, with 13 mil options. Ask suppliers for the minimum thickness and how it is measured. [2]
In one leading range only rods of 8 ft and longer carry a UL listing; shorter lengths are offered to IEC EN 62561-2 or without a listing. [2]
The 2025 edition lists coating-thickness, adhesion, electrical resistance, bending, environmental, resistivity, tensile and yield-to-tensile ratio tests, plus material and cross-section checks. [1]
Sectional rods can use compatible threaded couplers. nVent’s CR58 is a bronze 5/8-inch UNC example; TuAn’s 35 m depth is a supplier claim, not confirmation that a particular site can be driven to that depth. Match threads and obtain the installed-system design. [5] [3]
Sources checked 2026-10-09. Standards bodies and regulations define the requirements; manufacturer pages show published ranges for those models only. CNFX does not certify products or suppliers.
Ask for use case, specification boundaries, supplier type, and RFQ preparation information for this product.
Compare manufacturer profiles with relevant product and process capability.