How to Spot Fake or B-Grade Solar Panels in Pakistan

Three different things get sold as A-grade Tier-1 panels in this market, and they are not the same problem.

Counterfeits. A generic module wearing a Longi, Jinko or Canadian Solar sticker. Outright fraud.

B-grade sold as A-grade. A genuine panel from a real manufacturer that failed quality binning, priced two or three rupees below the A-grade rate so it feels like a bargain rather than a warning.

Wrong technology. A real, correctly manufactured P-type PERC panel described to you as N-type. Older technology, lower efficiency, faster degradation, sold at an N-type price.

The third one is the most common and the hardest to catch, because nothing about the panel is fake. Only the description is.

This guide is a field checklist. Run these tests before you pay, or at minimum before the panels leave the pallet, because once a module is bolted to your roof your leverage is gone.

Test 1: the fingernail test on the barcode

Start here, because it takes five seconds and catches most outright counterfeits.

On a genuine Tier-1 module, the barcode and serial are laminated inside the glass, printed onto a strip that sits under the front lamination during manufacture. It is part of the panel. You cannot lift it, peel it or scratch it off.

Counterfeit panels almost always carry the barcode on a paper sticker applied to the outside. If you can catch an edge with your fingernail, or scratch the print, you are holding a fake.

Look closely at the surface under angled light. A laminated code sits beneath the glass with no edge to catch. A sticker has a visible raised border and a slight shadow.

This single check is the highest-value ten seconds in the whole purchase.

Test 2: verify the serial with the manufacturer

Every genuine Tier-1 module carries a unique serial registered in the manufacturer’s database. All the major brands run public verification tools, and they are free.

Enter the serial, or scan the QR code with your phone. A genuine panel returns full product details: model, wattage, batch and production information. Check those returned details against what is printed on your panel. A serial that verifies but returns a different wattage or model is still a problem.

If the system returns “no record found,” stop and take it up with the seller before installation.

Two cautions. Use only the manufacturer’s own domain, never a third-party “verification” site, since several exist to harvest data. And verify a sample across the batch, not one panel, because a common trick is one genuine panel on top of a pallet of something else.

Test 3: read the nameplate properly

The label on the back should be crisp, machine-printed and permanently affixed.

Check for spelling errors and logo inconsistencies. Counterfeit labels frequently contain small misspellings, blurred printing, or a logo at slightly wrong proportions. Compare against images on the manufacturer’s official site.

Then check internal consistency. The nameplate lists model code, rated power, open-circuit voltage (Voc), short-circuit current (Isc), voltage and current at maximum power, and efficiency. Pull the datasheet for that exact model code from the manufacturer’s site and compare every figure. Fakes are often assembled from a real datasheet with one or two numbers wrong, because whoever made the label did not understand what they were copying.

Red flags: handwritten information, a sticker applied over an older label, a nameplate that looks newer than the panel, a model code that does not appear in the manufacturer’s catalogue, or a wattage the manufacturer never produced in that series.

Test 4: ask for the flash test report

Every A-grade module is flash tested at the factory, and the measured output is recorded. Genuine A-grade shipments come with this data.

B-grade stock generally does not. A seller who cannot produce flash test data for a batch is telling you something about what the batch is, regardless of how the invoice describes it.

Ask for it before payment. The answer arrives fast, and the hesitation is informative.

Test 5: physical inspection

Do this in daylight, with the panel out of its packaging, before it goes up.

Glass. Look along the surface at a shallow angle. You are checking for scratches, chips, waviness and any cloudy patch beneath the glass. Snail trails, thin dark lines tracking across cells, indicate microcracks and moisture ingress.

Cells. Colour should be uniform across every cell and consistent between panels in the batch. Visible mismatch is one of the most common B-grade markers. Check cell alignment and spacing, which is machine-precise on genuine modules and noticeably irregular on cheap counterfeits.

Busbars and soldering. On conventional panels, the busbar lines should be straight, evenly spaced and cleanly soldered. Wandering lines or visible solder blobs mean hand assembly.

Frame. Anodised aluminium, square corners, clean machining, no bends or dents. Press a corner joint; it should be rigid. Flexing indicates thin material.

Backsheet. Smooth and uniform, with no bubbling, scratching, discolouration or delamination. Yellowing on a supposedly new panel means it has been stored badly or is not new.

Junction box. Factory-sealed, firmly attached, rated IP67 or IP68. Adhesive applied by hand around the edges means the box has been opened or replaced. Cables should be proper solar-rated cable with moulded MC4 connectors, not generic wire.

Test 6: weight and dimensions

Counterfeits cut cost on materials, and materials have mass.

Pull the datasheet dimensions and weight for the exact model, then measure. A 645W Longi Hi-MO X10 should be roughly 2382 × 1134 mm and about 33.5 kg. A panel claiming to be that module while measuring noticeably smaller or weighing several kilograms less is using thinner glass, a thinner frame, or fewer and smaller cells.

Dual-glass panels in particular are heavy. A supposedly dual-glass module that feels easy to lift is not dual glass.

Specifications for the common high-output modules are in our Jinko 720W price and specs write-up if you need a reference point.

Test 7: the electrical check

This is the test that catches relabelled and underperforming panels, and almost nobody does it.

You need a multimeter and, ideally, a clamp meter with DC current capability. Do it outdoors in good sun, around midday.

Open-circuit voltage (Voc). Disconnect the panel from everything. Measure across the two output leads. The reading should be close to the nameplate Voc, typically within a few percent. Note that Voc rises in cold weather and falls in heat, so expect some variance.

Short-circuit current (Isc). With a clamp meter, short the leads and measure current. In strong sun this should approach the nameplate Isc. A reading substantially below rating in good conditions means the panel is not producing what its label claims.

Under load. Once installed, the string voltage and current at the inverter should track the sum of the panel ratings. If a new array consistently underproduces against a reasonable expectation, individual panels are worth checking.

A panel that fails these numbers is either B-grade, relabelled, or damaged. The label cannot tell you which. The meter can tell you that something is wrong.

Test 8: paperwork

Invoice. It should state brand, exact model code, wattage, quantity and grade. “Longi 585W” is not a model code. If a seller will not put the full code in writing before payment, walk away, because that vagueness is deliberate and it is the thing that makes a later dispute unwinnable.

Certifications. Genuine modules carry IEC 61215 and IEC 61730 as a minimum, often with TUV or UL marks. These should be printed on the nameplate and reflected in the documentation.

Warranty documentation. A-grade shipments include manufacturer warranty terms. Ask specifically what capacity retention is guaranteed and over what period. A warranty with no retention figure attached is marketing rather than a commitment.

Dealership proof. Ask whether the seller is an authorised distributor, and check the manufacturer’s site for its distributor listing.

The P-type problem

This deserves its own section because it is the most common deception and none of the tests above catch it.

The panel is genuine. The serial verifies. The nameplate is accurate. The manufacturer made it exactly as labelled. But the manufacturer labelled it as a P-type PERC module, and the dealer described it to you as N-type.

The only defence is the model code. Every manufacturer publishes which series are N-type and which are P-type. Get the code in writing, look up the series on the manufacturer’s own site, and confirm the cell technology yourself rather than accepting a verbal description.

If a quote says “N-type bifacial” without a model code, the quote is meaningless.

Price as a signal

The per-watt rate is the fastest sanity check available.

A-grade Tier-1 N-type currently trades at roughly Rs 40 to Rs 48 per watt. Premium back-contact modules sit at the top of that band. Anything offered dramatically below the range is telling you what it is.

A dealer offering premium-brand A-grade at Rs 29 per watt is not doing you a favour and has not found a special container. Current rates by brand are tracked in our solar panel price in Pakistan today guide, and the economics of the grade decision are covered in our A-grade vs B-grade solar panel prices breakdown.

Dealer red flags, before you get to the panels

Refusal to put the exact model code on the quotation.

No physical premises you can visit.

Full payment demanded upfront with no inspection at delivery.

Cannot produce flash test data or dealership proof.

Pressure to accept “same specification, different brand” at the last minute.

A price well below every other quote you have received, with a story attached to explain it.

What to do if you have already been sold fakes

Photograph everything: the nameplate, the barcode area, the serials, the invoice, and any messages where the seller described the product.

Run the serials through the manufacturer’s verification tool and screenshot the results. LONGi maintains a Pakistan contact address for exactly this kind of query.

Contact the seller in writing rather than by phone, stating the specific discrepancy. A written record matters if this escalates.

If the panels are not yet installed, do not install them. Installation weakens any claim and makes return practically impossible.

For amounts that justify it, consumer protection avenues exist at provincial level, and manufacturers do take counterfeit reports seriously because the brand damage is theirs.