摘要
结合具体案例,分析了有线数字电视机顶盒HDMI着火的原因。结果表明:有线网络信号传输链路中的信号地与用户家用电器设备保护地间的地电位差带来的瞬间泄放电流,造成了机顶盒HDMI输出端口处过热起火。按GB 8898-2011要求,在有线网络天线同轴插座与保护接地电路之间添加隔离器后,消除了着火隐患,并对有线数字电视机顶盒产品的设计和安全使用提出了建议。
Combining with a specific case, the cause of HDMI fire in cable digital TV set top box is analyzed. The results show that the instantaneous discharge current in the wired network signal transmission link caused by the ground voltage difference between the signal ground and the protected ground of the user's household electrical equipment leads to overheating and ignition at the output port of set top box HDMI. According to GB 8898-2011, adding isolator between coaxial socket of cable network antenna and protective grounding circuit, the hidden danger of fire is eliminated, and some suggestions on the design and safe use of cable digital TV set top box products are given.
