中文
含义
磁控管故障。微波炉能通电、转盘旋转、照明灯亮，但无法加热食物。磁控管（Magnetron）未能正常产生2450MHz微波辐射。
常见原因
- 磁控管灯丝开路或老化，发射能力下降
- 磁控管内部真空度下降（漏气），阳极电流异常
- 高压变压器（HVT）次级绕组短路或开路，无法提供磁控管所需的高压（约-4000V）
- 高压电容或高压二极管击穿，高压整流电路失效
- 磁控管天线帽烧蚀或陶瓷密封破裂
自助排查
- 观察微波炉运行时是否有正常的”嗡嗡”声但无加热——确认磁控管是否在工作
- 将一杯水（约200ml）放入微波炉加热1分钟，测量水温是否升高
- 使用万用表测量磁控管灯丝两个端子之间的电阻（应小于1Ω），以及灯丝对地绝缘（应大于1MΩ）
- 若灯丝对地短路或断路，需更换磁控管
English
Meaning
Magnetron fault. The microwave has power, the turntable rotates, and the light works, but it cannot heat food. The magnetron is not generating the 2450MHz microwave radiation required for cooking.
Common Causes
- Open or aged magnetron filament with reduced emission capability
- Degraded vacuum inside the magnetron (gas leakage) causing abnormal anode current
- Short or open circuit in the high-voltage transformer (HVT) secondary winding, failing to supply the -4000V needed
- Failed high-voltage capacitor or high-voltage diode, breaking the rectifier circuit
- Burnt magnetron antenna cap or cracked ceramic seal
Self-Check Steps
- Observe whether the microwave hums normally but does not heat — confirms the magnetron is being driven but not producing output
- Place a cup of water (200ml) inside and heat for 1 minute — measure temperature rise
- Use a multimeter to measure resistance across the magnetron filament terminals (should be less than 1Ω) and insulation from filament to ground (should be above 1MΩ)
- If the filament is shorted to ground or open, replace the magnetron