中文
含义
微波炉高压变压器故障。E3 表示主控芯片检测到高压变压器（HVT）初级或次级绕组异常——通常为绕组开路、短路或对地漏电，导致无法产生微波所需的高压。
常见原因
- 高压变压器初级绕组烧断（开路）
- 高压变压器次级绕组层间短路（绝缘击穿）
- 变压器铁芯磁短路（硅钢片绝缘失效，涡流增大）
- 变压器绕组对铁芯或外壳漏电（绝缘老化）
- 变压器过热导致内部温度保险（内置热保护器）熔断
- 高压电容或高压二极管击穿短路间接导致变压器过载损坏
自助排查
- 断电放电：拔掉电源插头，等待至少 10 分钟让高压电容充分放电（高压危险！）
- 检查外观：打开外壳目视高压变压器是否有烧焦、漆包线裸露、绝缘纸炭化或漏油痕迹
- 闻气味：是否有明显的绝缘漆烧焦气味——变压器过热的典型特征
- 测量绕组：用万用表电阻档测量变压器初级绕组（通常约 1Ω-3Ω）和次级绕组（通常约 100Ω-200Ω），与正常值对比；明显偏低或无穷大说明绕组损坏
- 呼叫售后：高压变压器更换涉及高压电路调试，必须由专业维修人员处理。请立即联系 Robam 售后（9510-5855）
English
Meaning
Microwave high-voltage transformer (HVT) failure. E3 indicates the main control chip detects an abnormality in the transformer primary or secondary windings — typically open circuit, short circuit, or ground leakage, preventing generation of the high voltage needed for microwave operation.
Common Causes
- Open primary winding in the high-voltage transformer
- Layer-to-layer short circuit in the secondary winding (insulation breakdown)
- Magnetic short circuit in the transformer core (laminated core insulation failure causing high eddy currents)
- Winding leakage to core or housing (insulation aging)
- Internal thermal protector (built-in thermostat) tripped from overheating
- High-voltage capacitor or diode short circuit causing transformer overload damage
Self-Check Steps
- Power off and discharge: Unplug the microwave and wait at least 10 minutes for the high-voltage capacitor to fully discharge (high voltage — dangerous!)
- Visual inspection: Open the housing and inspect the transformer for burn marks, exposed winding wire, carbonized insulation paper, or oil leakage
- Smell test: Check for a distinct burnt varnish odor — a classic sign of transformer overheating
- Measure windings: Use a multimeter in resistance mode. Primary winding typically reads 1Ω-3Ω, secondary about 100Ω-200Ω. Significantly lower readings indicate short circuits; infinite indicates open circuit
- Call support: High-voltage transformer replacement involves high-voltage circuit testing and must be performed by a qualified technician. Contact Robam after-sales service (9510-5855) immediately