Lighting inspection checks whether sampled products match the buyer-approved order requirements before shipment or at an earlier production stage. For lighting chains, switching the product on is only one part of the work. Our team also reviews electrical ratings, wiring, strain relief, connectors, transformer or adaptor details, workmanship, accessories, labels, barcodes, product dimensions, packaging, and the specific on-site tests assigned to the order.

This guide uses the UTS Working Instruction for Lighting Chain as its main technical basis. The working instruction defines default sampling, defect classifications, test items, sample levels, and reporting requirements for applicable lighting-chain products. These requirements must still be matched to the exact model, protection class, market, adaptor arrangement, rated input, approved specification, instruction manual, and client-specific inspection instruction. A value or test used for one lighting-chain configuration must not be transferred automatically to another product.

Before arranging the inspection, our office team reviews the purchase order, SKU breakdown, approved specification, approved sample, drawings, rating information, packaging artwork, instruction manual, barcode list, accessories, required markings, and buyer-defined test requirements. Where these documents conflict, our project service team obtains client clarification before the inspection. The factory’s temporary explanation does not replace the buyer-approved reference.

Lighting inspection does not replace product design validation, certification, laboratory testing, or destination-market regulatory assessment. UTS is a third-party inspection company. We do not issue certificates, authorize the use of product marks, approve declarations of conformity, or guarantee that a product complies with every market requirement. When marks or supporting documents are included in the inspection scope, our team compares the visible product information with the buyer-approved references.

Sampling and Defect Classification

The UTS Lighting Chain working instruction uses ISO 2859-1, or the equivalent ANSI/ASQ Z1.4 approach, with a single sampling plan for normal inspection. Its default main sample is based on General Inspection Level II. The working-instruction defaults are Critical: none permitted, Major: AQL 1.0, and Minor: AQL 4.0, unless the client has approved different criteria. ANSI/ASQ Z1.4 provides normal, tightened, and reduced attribute-sampling plans for percent nonconforming or nonconformities per 100 units.^[1]

The lot size still determines the code letter and main sample quantity. The AQL sample must not be confused with the quantity used for every on-site test. In the lighting-chain working instruction, some checks use the main Level II sample, many special tests use Special Inspection Level S-2, carton size and weight use one carton, and other quantities may be set by the client. The report should show the quantity used for each test instead of presenting one combined sample number.

Inspection area	Default WI sample basis	What the report should show
General workmanship and classified defects	General Inspection Level II	Lot size, code letter, sample size, critical/major/minor counts, and affected SKUs
Hi-pot, earth continuity, input power, and basic function	Level II where applicable	Model, rating, equipment, settings, checked quantity, failures, and evidence
Performance, gasket, wiring fixation, transformer, gauge, endurance, marking rub, wireless/timer, and internal checks	Special Inspection Level S-2 where applicable	Exact method, sample quantity, applicable product configuration, result, and post-test condition
Carton size and weight	One carton	Approved claim, actual result, unit, tolerance where applicable, and carton identification
Product size and weight, carton drop, and barcode checks	S-2 under the WI	Checked samples, method, actual findings, damaged units, unreadable codes, and mismatches

A critical finding is not absorbed into the major or minor AQL count. The working instruction treats a defect as critical when it is likely to create a hazardous or unsafe condition or fails a mandatory requirement. A major defect is likely to cause failure or materially reduce usability or saleability. A minor defect falls below the defined quality level without normally preventing use. The final classification depends on the actual severity, product construction, intended use, location of the defect, and buyer-approved criteria.

Electrical Function and Performance

Basic Function Check

The basic function check is performed on the Level II sample under the lighting-chain working instruction. The product should switch on and off without malfunction or intermittent operation. The setup must use the approved voltage, plug, adaptor or transformer, controller, timer, battery arrangement, and operating mode.

Depending on the approved product specification, our team records whether:

• All required lamps, light points, or illuminated sections operate.
• The switch, controller, mode sequence, timer, remote control, Wi-Fi, or Bluetooth function follows the instruction manual.
• The product avoids intermittent output, unexpected shutdown, abnormal noise, unsafe vibration, or movement during operation.
• Indicator lights and controls are complete, undamaged, and consistent with the actual operating state.
• The supplied adaptor, transformer, connector, and accessories belong to the correct SKU.

A general statement such as “function passed” is not enough. The report should identify the model, checked quantity, operating condition, required modes, failed functions, and affected samples.

Input Power and Defined Performance Checks

The working instruction requires input-power consumption to be compared with the rated input using the applicable market and product-category rule. The Level II sample basis applies unless the client specifies otherwise. The inspector should not select a tolerance from an unrelated appliance category. The applicable rated-input requirement must be confirmed from the working instruction, specification, product rating, or client instruction.

For the performance check, the lighting-chain working instruction uses S-2 and states that the unit is powered for 0.5 hour before the defined parameters are checked in an integrating sphere according to the specification. The listed parameters are:

• Power factor
• Color temperature
• Bulb luminance
• Beam angle

These measurements require the defined equipment, operating condition, warm-up period, product position, and approved limit. An on-site comparison should not be presented as a complete photometric laboratory assessment. If the required integrating sphere, reference specification, test condition, or suitable operator is unavailable, the result should be recorded as not performed or unable to verify rather than passed.

Wireless, Timer, and Sensitivity Functions

Where Wi-Fi, Bluetooth, timer, or another control function is included, the S-2 samples are checked against the instruction manual and buyer-approved requirements. The report should identify the device or application used, connection result, tested distance where defined, functions checked, and any reconnection or response failure.

The working instruction also lists sensitivity measurement with reference to the instruction manual. No universal sensitivity distance or acceptance value should be created when the approved manual or specification does not provide one.

Electrical Safety-Related On-Site Checks

Safety-related on-site checks are performed only when they apply to the exact lighting-chain construction and are included in the approved scope. They do not replace certification or controlled laboratory testing. Test voltage, connection points, equipment settings, current limits, duration, and acceptance conditions must be recorded.

Hi-Pot Test

The UTS lighting-chain working instruction assigns the hi-pot check to the Level II sample. It states that the test voltage is applied between live parts and accessible metal parts for 1 second, with a maximum breakdown current of 5 mA and no insulation breakdown. The working-instruction values are:

Market and class	WI test voltage	Use condition
Europe, Class I	1,500 V AC	Only when this classification and working instruction apply to the inspected model
Europe, Class II	4,000 V AC	Only when this classification and working instruction apply to the inspected model
USA	1,200 V AC	Only when the approved product and market instruction require this value

These values are not universal lighting limits. If the buyer-approved test document, product certification file, market requirement, or model construction specifies another method, our team follows the approved order instruction. A hi-pot check that is not completed must not be marked as passed.

Earth-Continuity Check

For an applicable Class I product, the working instruction assigns earth-continuity measurement to the Level II sample. For the European method listed in the WI, an earth-continuity tester is used at 12 V/25 A with a maximum result of 0.1 ohm. For the USA method, the WI requires an ohm meter or earth-continuity tester and good continuity. The report should record the equipment, connection points, reading, sample identification, and approved acceptance basis.

Transformer or Adaptor Check

For a lighting chain supplied with an adaptor, the working instruction assigns an S-2 transformer check. Our team verifies the approved markings and, where the short-circuit test is included, records whether the transformer emits flame, molten material, glowing particles, or burning drops and whether the thermal fuse operates. This test must follow the approved setup and must not be added to a product that does not use the applicable adaptor construction.

Wiring, Internal Construction, and Fixation

Wiring Fixation

The working instruction assigns wiring-fixation checks to S-2. For applicable Class II and Class III products, the specified check is 40 N applied 25 times without cutting. For rope light, the WI specifies 60 N applied 25 times. For a rope-light end cap, it specifies 60 N for 10 seconds. The report should identify the exact point where the force is applied, the product configuration, the number of cycles, and the post-test condition.

A force value must not be transferred from a rope light to a different lighting product. Where the construction, test point, or approved method does not match the WI, the requirement should be clarified before testing.

Critical Components and Internal Check

The S-2 internal check in the lighting-chain working instruction covers connectors, wires, terminals, crimping, fasteners, insulation, critical components, and enclosure joints. The defined review includes:

• Terminal blocks with wire protection or suitable cable bushes over wire ends.
• Crimp connections that secure both the conductor and insulation.
• Connections and receptacles consistent with the approved construction.
• A 10 N pull check on applicable connections with the insulation clamp open.
• Assembly screws that are effectively fixed.
• Critical components that are stable and consistent with the approved reference, such as the plug, power cord, switch, and fuse where applicable.
• Effective joining of applicable braze points, flat pins, and insulated bushings.
• Wire insulation without visible damage or scratches.
• Pressure-assembled and glued enclosure points that remain durable and secure.

Internal photographs should show the inspected sample and the affected part clearly. A visual internal check cannot prove the long-term reliability or technical performance of an untested component.

Gaskets and Moisture-Protection Construction

The S-2 gasket check applies where gaskets provide protection against moisture. The working instruction requires the gasket to remain correctly positioned at the lampholder when the lamp is removed. The WI states that this check is not applicable to battery-operated lighting chains or lighting chains with an adaptor output of no more than 12 V.

Our team may also record missing, displaced, damaged, or poorly fitted gaskets, covers, cable entries, and end caps. A visual gasket check does not confirm an IP rating. No fixed humidity percentage or general moisture threshold should be invented for an ordinary inspection.

Assembly, Workmanship, and Accessories

Workmanship and Construction Defects

The lighting-chain working instruction includes packaging, labeling, construction, workmanship, function, and accessory defects. The report should use the approved classification and describe the actual effect instead of copying a defect name without context.

Area	WI-based inspection points
Surface and construction	Color deviation, deformation, shrinkage, rust, oxidation, grease marks, poor alignment, weak bonding, poor ultrasonic welding, incomplete rivets, over-tightened or slipped screws, and loose or false welding
Hazard-related observations	Accessible sharp points or edges, foreign metal or plastic material, loose strain relief, damaged insulation, and malfunctioning safety interlock or overturn switch
Operation	Vibration or sliding during operation, abnormal starting or operating noise, non-smooth movement, and intermittent function
Accessories	Missing accessories, items not matching the parts list, accessories that do not fit, and color, design, or size that does not match the main product

The WI may classify some safety-related conditions as critical and other workmanship conditions as major or minor. The final record should identify the affected sample quantity, exact location, severity, photo evidence, and approved reference.

Interchangeability, Endurance, and Marking Durability

The working instruction assigns the following checks to S-2 where applicable:

• Interchangeability gauge check: use the approved standard gauge to verify the dimensions controlling screw-cap interchangeability and confirm that the parts fit correctly.
• Endurance check: operate at rated voltage under no load for four hours, then open the product and inspect for internal damage.
• Rub check: rub the applicable marking with a piece of cotton and water for 15 seconds, then record whether the marking remains legible and attached.

The report should not claim long-term product life from one four-hour on-site endurance check. It records the result under the defined WI condition only.

Product and Carton Measurements

The lighting-chain working instruction assigns product size and weight measurement to S-2 and carton size and weight measurement to one carton. Where applicable, the WI compares the result with the label or specification claim using a tolerance of ±5%. This tolerance should be used only when the same WI requirement applies and no different buyer-approved tolerance controls the order.

The report should state the approved value, actual result, unit, tolerance, measuring equipment, checked quantity, and affected SKU. If no approved dimension or weight exists, our team records the actual finding without creating a pass/fail limit.

Labels, Marks, and Barcode Checks

Rating Labels and Required Information

The working instruction reviews product identification, responsible-party information where required, net quantity, destination-language statements, country-of-origin marking where required, warnings, safety information, battery polarity and voltage information, and label adhesion. The product, adaptor, gift box, inner carton, shipping carton, purchase order, and approved artwork should remain consistent.

Where the destination market requires more than one language, our team checks whether the buyer-approved language version is present and whether the wording matches the approved artwork. This comparison does not confirm legal sufficiency or translation accuracy.

Market Marks and Certification Marks

Lighting products may display CE, WEEE, CB-related information, UL, CSA, ETL, GS, VDE, RCM, CCC, CQC, or other marks depending on the product and market. These marks are not interchangeable:

• CE marking: the manufacturer is responsible for identifying applicable EU requirements, completing the required conformity-assessment process, preparing technical documentation, issuing the EU Declaration of Conformity where required, and affixing the marking.^[2]
• CB Scheme: the IECEE CB Scheme supports mutual acceptance of test reports and certificates for electrical and electronic equipment safety.^[3]
• UL, CSA, ETL, and other NRTL marks: when used under the U.S. NRTL program, applicability depends on the recognized laboratory, exact product, test standard, site, and certification scope.^[4]
• RCM: the Regulatory Compliance Mark is used under applicable Australian and New Zealand electrical-safety and communications arrangements. A CE mark does not by itself authorize use of the RCM.^[5]
• GS Mark: GS is a voluntary German tested-safety mark awarded through an authorized GS body.^[6]

UTS does not issue, approve, renew, or validate these marks. When mark verification is included, our team checks presence, artwork consistency, model information, position, and consistency with the supporting documents supplied by the client. A visible logo alone does not prove that the exact model, factory, and construction are covered by a valid authorization.

Barcode and QR-Code Verification

The lighting-chain working instruction assigns barcode readability checking to S-2. The reader is verified before use, the selected code is scanned, and the displayed number is compared with the printed human-readable number and the buyer-approved requirement.

For all checked barcode or QR-code samples within the agreed scope, the scan-success rate must be 100%. The practical check confirms:

• The printing is clear, complete, correctly positioned, and not visibly damaged.
• The code scans successfully.
• The decoded information matches the human-readable number.
• The decoded information matches the approved SKU, model, or barcode list.
• The product, gift box, inner carton, and shipping carton carry the correct corresponding information.

Any unreadable code or decoded-data mismatch should be recorded, corrected, and rechecked according to the client’s requirements. A result below 100% must not be described as acceptable for the checked samples.

Packaging and Shipping-Carton Drop Test

Packaging Condition

The lighting-chain working instruction covers damaged, wet, crushed, deformed, or incorrectly constructed shipping cartons; mold or mildew; irritating odor; loose products; missing accessories; mismatched selling-pack information; and unstable retail packaging. Our team also checks sealing, internal protection, product position, accessory separation, cable arrangement, gift-box condition, and shipping marks against the approved packing instruction.

No fixed moisture percentage or general humidity threshold should be invented. The report records visible dampness, water marks, mold, unusual odor, condensation risk, wet packaging, affected quantity, and the observed location.

Shipping-Carton Drop Test

When the drop test is included, the UTS lighting-chain working instruction assigns S-2. Before testing, the carton is opened and the contents are inspected. The carton is then repacked using the same materials and method and dropped onto a flat, rigid surface using the 1-corner, 3-edge, and 6-face sequence.

Packaged weight	WI drop height
Below 21 lb (9.5 kg)	30 in (76 cm)
21 lb (9.5 kg) to below 41 lb (18.6 kg)	24 in (61 cm)
41 lb (18.6 kg) to below 61 lb (27.7 kg)	18 in (46 cm)

After the test, the WI requires the carton to remain capable of providing reasonable protection, the gift box to remain saleable, and each inspected product to remain free from damage or malfunction. The report should separate outer-carton damage, retail-pack damage, product damage, loose parts, and function failures. A carton that stays closed does not support a pass result when the product inside is damaged.

Inspection Stage and Report Review

Initial Production Inspection is usually arranged when approximately 5%–10% of the order has been produced. It is useful when the product uses a new transformer, wiring construction, controller, connector, gasket, or packaging design. During Production Inspection is usually arranged when approximately 30%–50% of the goods have been produced and can identify repeated wiring, assembly, function, or packing problems while correction remains practical.

Final Random Inspection is arranged when production is 100% complete and at least 80% of the goods are packed. The final report should show production and packing status, lot size, sampled SKUs, default or client-specific AQL, defect counts, every on-site test quantity, equipment and settings, actual measurements, unavailable tests, labels, barcode results, packaging findings, and photo evidence.

A lot that remains within the workmanship AQL limits may still require buyer review when a critical defect, failed hi-pot or earth-continuity check, wrong voltage, incorrect adaptor, failed transformer check, unreadable barcode, or repeated function failure is found. The buyer remains responsible for corrective action, acceptance of deviations, re-inspection, and shipment release.

UTS applies the order-specific working instruction together with the buyer-approved specification and inspection criteria. The report documents what was available, what was sampled, which WI tests were applicable, what conditions were used, and what failed. It does not guarantee zero defects, validate certification, or remove the supplier’s responsibility for manufacturing quality.