PV Grounding Clip Specifications: What to Put in Your RFQ

A specification for pv grounding clips is only useful if it is unambiguous to someone who cannot see your project. Most disputes on this product do not come from bad manufacturing — they come from a drawing that could reasonably be read two ways, where the supplier read it the cheap way and the buyer read it the expensive way.

This is a practical specification checklist, written around what the standards actually require.

The three specification families you will meet

Suppliers will quote against whichever family your market uses, and the part can usually be built to any of them:

• IEC 62548 — Design requirements for photovoltaic arrays.
• UL 2703 — Mounting systems and clamping devices for PV modules.

The mistake is to specify a standard reference without specifying the class or grade within it. If you write only the standard number, the supplier will quote the lowest class that satisfies it. Write the standard and the level you want.

Dimensional data that has to be on the drawing

For this product the critical dimensions are: M8 bolt fixing, tooth height 0.8–1.5 mm, compatible with standard mid and end clamp footprints.

Three rules that prevent most dimensional disputes:

1. Give tolerances on every functional dimension, not just the nominal values. A nominal dimension with no tolerance is legally “as the supplier chooses”.
2. Say which dimensions are functional and which are cosmetic. Suppliers prioritise what you prioritise, and they cannot guess.
3. State the gauge or measuring method where a dimension is critical. Two inspectors with different methods will disagree about the same part.

Material and grade

The base specification is stainless steel or copper alloy with a hardened penetrating tooth. Grades commonly offered include:

• AISI 304 stainless
• AISI 316 for coastal
• copper alloy for high-conductivity paths
• galvanised steel for low-duty

Ask the supplier to state the grade on the quotation, not on an assumption. Grade substitution is the single most common silent cost reduction, and it is usually invisible in the finished part — a 201 stainless component looks exactly like a 304 one until the second winter.

Surface treatment

The usual finish for this product is passivated stainless or plated copper alloy; the penetrating tooth must stay bare to bite through anodising.

Two points worth writing into the order:

• A measured requirement, not a process name. “Hot-dip galvanised” is a process; “70 µm minimum, tested by coating mass on three parts per batch” is a requirement.
• What happens at cut edges and drilled holes, if any. These are where coatings are habitually broken and where corrosion starts.

Type tests and routine tests

These are different things and are frequently confused in quotations:

• Type tests qualify the design once. On this product: bonding resistance test; penetration depth check; salt spray 1000 h.
• Routine tests are run on every batch: thermal cycling with current injection.

Specify which type-test reports you want supplied as documents, and which routine test results must accompany each shipment. On a first order, ask for the type-test report before you place it.

The failure modes your specification should be closing

• High bonding resistance — a tooth that is too shallow to pierce the anodised layer, giving a path that reads fine on a multimeter and fails under fault current
• Tooth flattened on installation — hardening skipped, so the tooth deforms instead of penetrating

Each of these can be turned into one line in the specification. That is the real purpose of writing it out: not bureaucracy, but making the specific failure you are worried about somebody’s explicit responsibility.

A specification skeleton you can reuse

1. Scope: PV Grounding Clip to be supplied as grounding clip, earthing clip, bonding washer.
2. Dimensions and tolerances: M8 bolt fixing, tooth height 0.8–1.5 mm, compatible with standard mid and end clamp footprints.
3. Material: stainless steel or copper alloy with a hardened penetrating tooth; grade AISI 304 stainless or better.
4. Standard: IEC 62548 — Design requirements for photovoltaic arrays; UL 2703 — Mounting systems and clamping devices for PV modules.
5. Finish: passivated stainless or plated copper alloy; the penetrating tooth must stay bare to bite through anodising.
6. Tests: bonding resistance test; penetration depth check; salt spray 1000 h; thermal cycling with current injection.
7. Marking and packing: 500 pcs per bag, 5,000 pcs per carton.
8. Inspection: pre-shipment, against this specification, with photo evidence and test records.

Related: the pv grounding clip quality inspection checklist turns this specification into an inspection plan you can hand to a third-party inspector.