| Solar Module Quality |
Cell technology, rated output, power tolerance, temperature coefficient, mechanical load rating, and degradation commitment. |
IEC 61215 for design qualification and type approval; IEC 61730 for photovoltaic module safety qualification. |
Request the exact module model, independent test reports, flash-test data, serial-number traceability, and a published product warranty. |
Only a generic “CE” logo is provided without a model number, test report, or technical datasheet. |
High |
| Inverter Safety |
Conversion efficiency, maximum DC voltage, MPPT range, anti-islanding function, enclosure rating, and grid compatibility. |
IEC 62109-1 and IEC 62109-2 address safety requirements for power converters used in photovoltaic systems. Grid-code compliance depends on the destination market. |
Confirm the exact grid standard required by the importing country, such as applicable EN, VDE, UL, or national requirements, before shipment. |
The supplier lists “universal grid support” but does not identify the approved grid profile or firmware version. |
High |
| Battery Safety |
Battery chemistry, usable capacity, battery-management system, cycle conditions, thermal protection, and transport documentation. |
IEC 62619 is commonly used for safety requirements of industrial lithium secondary cells and batteries. UN 38.3 testing is required for the transport of applicable lithium batteries. |
Obtain the battery test report, UN 38.3 test summary, safety data sheet, rated conditions, and clearly stated usable—not only nominal—capacity. |
Capacity is quoted without voltage, depth-of-discharge limits, temperature range, or transport test documentation. |
High |
| Electrical Protection |
Overcurrent protection, DC isolator, surge protection, grounding, residual-current protection, and cable sizing. |
Protection requirements must follow the installation code and electrical regulations of the destination market. Component-specific IEC or UL approvals should be verified separately. |
Request a single-line diagram, protection-device ratings, wiring diagram, earthing instructions, and installation limits for each kit configuration. |
Protection devices are described as “included” without ratings, manufacturer datasheets, or a wiring diagram. |
High |
| Ingress Protection |
Resistance of outdoor enclosures to dust and water, including connectors, junction boxes, battery cabinets, and inverter housings. |
IP ratings are defined under IEC 60529. The rating applies to the tested enclosure and does not automatically cover the complete system after installation. |
Verify the IP rating on the exact product datasheet and confirm whether cable glands, connectors, and installation orientation are included in the test scope. |
An IP rating is advertised for the system although only one enclosure was tested. |
Medium |
| Factory Quality Management |
Incoming inspection, process controls, final inspection, calibration, nonconformance handling, and batch traceability. |
ISO 9001 certification demonstrates a quality-management system; it does not by itself certify the performance or safety of a particular solar product. |
Check the certificate scope, issuing body, validity, factory address, audit status, and whether the certificate covers the actual production site. |
An ISO certificate is supplied with an unrelated address, expired validity, or no identifiable certification body. |
High |
| Market Certifications |
Regulatory documents required in the destination country or region, including electrical safety, electromagnetic compatibility, chemical restrictions, and radio requirements where applicable. |
CE marking is supported by an EU Declaration of Conformity for applicable EU legislation. RoHS addresses restrictions on specified hazardous substances in applicable electrical and electronic equipment. |
Request the Declaration of Conformity, technical file references, test reports, and the exact model numbers covered by each document. |
A CE logo is presented as a universal quality certificate, or documents do not match the shipped model. |
High |
| Performance Verification |
Rated power, efficiency, battery capacity, standby consumption, operating temperature, and output stability. |
Performance claims should be linked to defined test conditions, measurement methods, tolerances, and laboratory reports. |
Require a pre-shipment inspection or sample test covering output, insulation, polarity, communication, charging, and protective shutdown functions. |
Marketing specifications omit test conditions or use peak values as continuous operating ratings. |
High |
| DIY Installation Scope |
Whether the kit is plug-and-play, requires a licensed electrician, or involves utility interconnection and permitting. |
Installation rules are determined by local electrical, building, fire, and utility regulations; certification does not replace local approval. |
Obtain a country-specific installation manual, circuit limits, connector compatibility details, and a clear list of work requiring qualified personnel. |
The supplier promises unrestricted DIY installation for grid-connected equipment in every country. |
High |
| Warranty Coverage |
Product warranty period, performance warranty, covered components, labor, shipping, exclusions, and remedy procedure. |
Warranty terms are contractual and vary by product. A solar module product warranty and a module performance warranty are separate commitments. |
Compare warranty start date, claim evidence, replacement or refund remedy, freight responsibility, transferability, and whether accessories have shorter coverage. |
Warranty duration is advertised without exclusions, claim address, remedy terms, or written conditions. |
High |
| Battery Warranty Conditions |
Cycle count, energy throughput, depth of discharge, temperature, state-of-charge limits, and retained-capacity threshold. |
Battery warranties commonly depend on operating conditions and may end when either a time limit or throughput/cycle limit is reached. |
Request a written warranty table showing the retained-capacity threshold, permitted operating window, exclusions, and proof required for a claim. |
Only a number of years is stated; cycle limits, usable capacity, and operating conditions are not defined. |
High |
| After-Sales Support |
Response time, remote diagnostics, firmware support, spare parts, replacement process, and technical documentation. |
Support quality is best evaluated through written service-level commitments and a documented escalation process. |
Confirm support channels, normal response time, spare-parts availability, remote-access requirements, and whether firmware updates remain available after purchase. |
Support is limited to a sales contact, with no troubleshooting procedure or replacement-part policy. |
Medium |
| Supply-Chain Traceability |
Factory identity, bill of materials, lot numbers, serial numbers, production date, and component consistency. |
Traceability records should connect the shipped product to its factory, production batch, test results, and applicable certificates. |
Request sample serial numbers, packing-list details, production records, and written notice procedures for component substitutions. |
Product labels, certificates, and invoices use inconsistent model numbers or factory information. |
High |
| Shipping and Packaging |
Packaging strength, moisture protection, palletization, dangerous-goods classification, and damage inspection procedure. |
Lithium batteries may be subject to dangerous-goods transport rules. UN 38.3 documentation and carrier-specific requirements should be checked before shipment. |
Confirm packing photographs, carton dimensions, gross weight, battery shipping classification, labels, and the process for reporting transit damage. |
Battery shipments are offered without transport documents, compliant labels, or defined insurance responsibility. |
High |
| Commercial Evaluation |
Total landed cost, minimum order quantity, sample policy, payment terms, lead time, and replacement-part pricing. |
Supplier quotations should separate product price, tooling or customization, inland freight, export charges, insurance, duties, taxes, and destination delivery. |
Compare at least three like-for-like quotations using the same system capacity, certification scope, Incoterm, warranty coverage, and inspection requirements. |
The lowest quotation excludes certification, accessories, freight, testing, or warranty-related costs. |
Medium |
