Electrical Appliance Inspection

Electrical Inspection Services of Hua Jian Company

Guangzhou Huajian Commodity Inspection Co., Ltd. is a third-party inspection company registered and approved by relevant national authorities. It specializes in third-party inspections, product examinations, on-site inspections, and integrated inspection services. Adhering to the principles of "safety, assurance, and commitment," the company has established long-term cooperative relationships with numerous enterprises. We warmly welcome friends from all sectors to visit, inspect, and discuss business opportunities.

Third-party inspections typically occur when manufacturers need to export goods, and overseas buyers cannot personally inspect the products. In such cases, they entrust third-party personnel to conduct the inspections.

1. Standard Requirements for Manuals

Manuals must include safety warnings or instructions in the official language. They should provide guidance on handling damaged power cords and clarify whether the appliance can be immersed in water for cleaning. Warnings regarding user installation and maintenance must also be included.

2. Basic Protection Against Electric Shock

Standard test fingers and standard test probes must not access live parts, functional insulation, or live parts isolated only by paint, enamel, ordinary paper, textiles, or oxide layers.

For Class II appliances or Class II structures, standard test fingers must not access basic insulation.

Openings on certain appliances must be tested with a jointless test finger applying a force of 20N to assess recoverability.

For Class II appliances or Class II structures, standard test probes must not access hazardous live parts.

3. Stability

Except for fixed appliances and hand-held appliances, other appliances intended for use on surfaces such as countertops or floors must have sufficient stability.

Place the appliance on a plane inclined at 10 degrees to the horizontal, in any normal position during use, with the power cord arranged in the most unfavorable state on the plane.

The appliance should not tip over.

For appliances with heating elements: 15 degrees;

If the appliance tips over, conduct a temperature rise test.

4. Mechanical Hazards

Moving parts on appliances, as long as they are compatible with the tool's use and operation, should be positioned or enclosed to ensure adequate protection against personal injury during normal use.

Protective enclosures, guards, and other protective devices must have sufficient mechanical strength and should be non-removable parts.

Use a test finger with a circular stop of 50mm diameter, applying a force of 5N.

The test finger must not access moving parts that could cause personal injury.

5. Mechanical Strength

The enclosure must withstand impact tests. After impact, there should be no exposure of live parts, insulation damage, or reduction in creepage distances.

Test requirements: 0.5J, 3 times.

Joule (abbreviated as J) is the international unit of heat, energy, and work. One joule is defined as the work done by a force of one newton moving an object one meter. 1 joule = 1 newton-meter = watt-second = 0.24 calories.

6. Insulation Withstand Voltage Test

Products must undergo 100% testing before leaving the factory. This test serves as an indicator of product quality and electrical safety.

The test involves applying a voltage higher than the normal operating voltage to the product for a specified duration. If no insulation breakdown occurs, the product passes the test.

The test voltage should be determined based on relevant safety standards, operating voltage, and insulation等级. AC voltage is typically used. If components span the insulation under test, DC voltage is recommended, but the test voltage must be 1.414 times the AC test voltage.

7. Grounding Impedance Test

The grounding impedance test measures the impedance between the product's grounding point and its外壳 or metal parts by applying a constant current (typically between 10-40A).

IEC: For general products, the measurement is 25A, and the impedance must not exceed 0.1Ω.

8. Input Power Requirements

9. Requirements for Handles and Knobs

They must be securely fixed.

For those not subject to axial force: apply a 15N axial force for 1 minute.

For those可能 subject to axial force: apply a 30N axial force for 1 minute.

During normal use, users should only接触 metal parts separated from live parts by double insulation or reinforced insulation.

If the shaft is metal and may become live in case of insulation failure, accessible parts of handles and knobs must be separated from the shaft by supplementary insulation.

10. Structural Requirements

Ensure safety distance requirements are met.

Drainage hole requirements: round holes with a diameter greater than Φ5mm, square or polygonal holes with at least one side greater than 3mm, and an area not less than 20mm² (e.g., electric kettles).

There should be no sharp edges, corners, or ridges to prevent personal injury.

Components (such as switches, thermostats, etc.) must be fixed appropriately to prevent sliding or loosening.

Surfaces where wires pass must be smooth and free of sharp edges, corners, or ridges that could damage insulation.

11. Grounding Requirements

Anti-loosening measures should be in place (e.g., serrated washers).

Screws providing grounding continuity must be threaded into metal.

The ground wire should be longer than the live and neutral wires. If detached, the live and neutral wires should disconnect first, followed by the ground wire.

Yellow-green wires should only be used for grounding and must be sufficiently thick.

The impedance between grounding terminals and grounded metal parts should be low, not exceeding 0.1Ω.