Electrical Appliance Inspection

Knowledge on Inspection of Multi-purpose Power Strips

1. Non-compliant labeling mainly manifests in the absence of manufacturer or seller identification marks and model types on the main components of fixed sockets. These converters fail to fully indicate the rated current or power with the word MAX (or maximum), failing to alert consumers to safe electricity usage; products without certification bearing the CCC mark constitute clear fraudulent behavior against consumers.

2. Non-compliant dimensional checks mainly show that the distance from the plug pins to the edge is less than 6.5mm, the socket openings are too large, and the stop gauge can be inserted into the socket; the metal contact sleeves are too close to the panel, allowing non-contact gauges to touch the live contact sleeves of the socket, and the stop gauge can be inserted into the socket; for two-pole sockets, the distance between live contact sleeves and the panel should be no less than 8.4mm; for two-pole sockets with grounding, the distance between live contact sleeves and the panel should be no less than 10.3mm; the use of multi-hole socket types that do not meet standard requirements. Some manufacturers, in pursuit of versatility and appearance, overlook dimensional requirements due to a lack of thorough understanding of the standards.

3. Non-compliant grounding measures mainly manifest in grounded sockets lacking grounding contact sleeves, or some sockets having grounding contact sleeves but no grounding wire connection; when the plug is inserted, the current-carrying pins become live before the grounding pin and disconnect later.

4. Non-compliant temperature rise mainly manifests in temperature rise values exceeding 45K, solder joints coming apart during temperature rise tests, some products having very small conductor cross-sectional areas, smoking after power-on, melting wires, and burnt ground wires. The cross-sectional area of the power cord assembled in the product is far less than 0.75mm², posing significant safety risks.

5. Non-compliant heat resistance mainly manifests in deformation of the casing and socket openings after the 100°C heat resistance test, switches failing to operate, and indentation diameters exceeding 2mm after the 125°C ball pressure test. These issues reflect manufacturers' weak quality awareness, using inferior raw materials or components to reduce costs. These materials soften at high temperatures, potentially causing product deformation and exposure of live parts,极易 resulting in electric shock hazards.

6. Non-compliant electrical clearance mainly manifests in electrical clearances between live parts, and between live parts and external assembly screws and grounded circuit components being less than 3mm. Non-compliant electrical clearance can easily cause short circuits, leading to personal injury and fire hazards. These issues reflect defects in the product safety design of manufacturers, lack of monitoring during the process assembly, and absence of product inspection.

7. Non-compliant flame resistance mainly manifests in flames not extinguishing within the specified time after removing the ignition source (glowing wire), and burning droplets igniting the tissue paper placed under the product. Combustion non-compliance is mainly due to manufacturers' weak quality awareness, using non-flame-retardant, cheap materials to reduce costs, resulting in products that do not meet standard requirements and are highly prone to fire, causing losses.

8. Non-compliant structure mainly manifests in sockets having grounding contact sleeves but plugs lacking grounding pins; socket contact assemblies failing to ensure metal contact on at least two opposite sides of each pin; improper adjustment of wire length, where if the flexible cable slips, the grounding wire bears the force first.

9. Non-compliant electrical strength mainly manifests in flashover phenomena during testing. This reflects manufacturers using substandard materials to reduce production costs, passing off inferior products as genuine.

10. Non-compliant protection against electric shock mainly manifests in any pin of the plug being able to engage with the live contact sleeve of the socket while any other pin is in an accessible state (also known as single-pole insertion); for sockets with protective shutters, live parts can be touched with a probe. Such issues easily lead to electric shock phenomena, endangering life safety.