Microwave oven inspection process - Inspection and certification services for factories

2025年10月22日

As a necessary appliance in modern kitchens, the quality and safety of microwave ovens directly affect the usage safety and cooking experience of users. To ensure that the products meet industry standards and quality certification requirements, establishing a professional inspection process is of vital importance. This article will systematically introduce the inspection standards, testing methods, and certification requirements for key components of microwave ovens, providing a complete quality control guide for enterprises.
I. Core Component Inspection and Certification Standards
1. Magnetic Control Tube Quality Certification
Electrical Performance Test Standards:
Filament inter-electrode resistance: Measured using the Rx1 setting, it should be in the conducting state (with a very small resistance) under normal conditions.
Filament insulation against the housing: Measured at the Rx10k setting, the normal resistance value is ∞ (fully insulated)
The transmitting head relative to the housing: Rx1 mode for measurement, normal state is open circuit.
Certification requirements: Any abnormal resistance value is classified as a non-conforming product.
2. Transformer Performance Certification
Winding Resistance Test Standard:
Primary winding: 2 - 2.5 Ω (Rx1 setting), open circuit or less than 1.2 Ω is considered不合格.
Secondary filament winding: The resistance is extremely low, and the output voltage is AC 3.4V ± 5%
Secondary high-voltage winding: 100 - 150 Ω, output voltage AC 2100V ± 10%
Certification focus: Strictly control within the tolerance range to ensure stable power output
3. High-voltage Diode Certification
Forward and Reverse Characteristic Test:
Forward resistance: 150 - 300 kΩ (at Rx10k setting)
Reverse resistance: ∞ (completely blocked)
Certification standard: If the measurement exceeds the range or there is any resistance, it is considered non-compliant.
4. High-voltage capacitor quality certification
Charge and discharge characteristic verification:
Inter-pole test: Both forward and reverse charging and discharging phenomena were observed, and the resistance value pointed to 10 MΩ.
Exterior insulation: The resistance between each pole and the exterior is ∞.
Certification requirements: If there is no charging or discharging characteristic or insulation failure, it is considered unqualified.
5. Bidirectional Diode Certification (applicable to some models)
Forward and reverse tests: Resistance values are both ∞
Certification standard: Any resistance present is considered non-compliant.
6. Motor System Certification
Standard resistance values for each motor:
Timer motor: 15 - 20 kΩ (Rx1k setting)
Rotary motor: 7-10 kΩ (Rx1k setting)
Fan motor: 200-300 Ω (Rx10 setting)
Certification requirements: Any abnormal resistance value will be deemed as a defective product.
II. Common Fault Repair Certification Process
1. Timer System Certification
Power divider contacts: Charred and non-functional require professional handling
Timing motor failure: The timer does not reset to zero. It needs to be replaced or repaired.
Certification standard: Ensure that the timing accuracy complies with the GB/T standard.
2. Capacitor Certification - External Short Circuit Detection: This is indicated by no heating or tripping of the fuse.
Insulation treatment standard: Wrapped with multiple layers of insulating paper and fixed in an upright position.
Certification requirement: Pass the pressure resistance test certification
3. Transformer Process Certification
Winding connection quality: The secondary high-voltage winding is securely connected to the core.
Core fixation standard: No abnormal noise, accurate position
Certification focus: Through vibration testing and temperature rise testing
4. High-voltage safety system certification
Inspection of fuse blowout: Identify the root cause to prevent recurrence of the fault
Alternative solution verification: Careful assessment is required for the substitution of single-strand copper wire
Certification standard: Compliant with electrical safety regulations
5. Magnetic Control Tube Durability Certification
Ignition treatment for the transmitting head: A safety assessment is required when removing the outer cover.
Service life test: Certified through accelerated aging experiment
Certification requirements: Comply with electromagnetic radiation safety standards
6. Durability Certification of Structural Components
Door handle strength test: Breakage at the hook requires professional repair
Plastic part material certification: Passed high-temperature resistance and impact resistance tests
Certification standard: Meets mechanical strength requirements
7. Computer board reliability certification
Primary transformer inspection: Temperature protection failure requires professional handling
Zener diode thermal stability: Tested through high and low temperature cycling.
Certification focus: Ensure the long-term stability of the control system
III. Inspection and Certification Process Standards
1. Sampling Inspection Plan
Implement statistical sampling in accordance with the GB/T 2828 standard
Safety-critical components are subject to a comprehensive inspection system.
Establish a complete quality traceability system
2. Test environment requirements
Standardized electrical laboratory environment
Use calibrated and qualified testing equipment
Strictly follow the safety operation procedures
3. Defect Level Determination
Critical Defect: Projects that affect safety are strictly prohibited.
Serious defect: Major functions fail under strict control
General defect: Minor appearance defects are within the acceptable range as per the standards.
IV. Key Control Matters for Factory Inspection
To ensure that the quality of microwave ovens consistently meets the certification requirements, during the factory inspection process, the following matters need to be given priority attention:
Supplier Management: Establish a certification system for key component suppliers
Production process control: Develop operation standards for key assembly and debugging procedures
Calibration of testing equipment: Regularly calibrate all electrical safety testing devices
Quality management system: Certified by ISO9001 quality system standard
Personnel qualification certification: Electrical inspectors must hold certificates to work.
V. Continuous Quality Improvement Certification
1. Fault Data Analysis
Establish a fault database and conduct statistical analysis
Identify common failure modes and formulate improvement measures
Implement preventive quality control measures
2. Handling of Customer Feedback
Establish a rapid response mechanism for customer complaints
Incorporate customer feedback into the quality improvement cycle
Conduct regular customer satisfaction surveys
Inspection and Certification Summary
The inspection and factory verification of microwave oven products is a highly technical and systematic project that requires comprehensive testing and certification covering core components, electrical safety, and usage performance. By establishing a professional inspection process and strict quality standards, enterprises can ensure that microwave oven products meet the requirements of mandatory national certification, providing consumers with safe, reliable, and durable kitchen appliances.