Identification of the cause of the outlet fire

When there is an overload problem in the circuit, it is easy to cause the socket to be burned out. In addition, there are other reasons why the socket is often burned out. For example, the socket wiring is not standardized, there is a virtual connection phenomenon, or the socket quality is not good, which will also cause the socket to be burned out.
There are four reasons why the socket burns out: the current is too large and exceeds the load, and the entire circuit generates a lot of heat, causing the socket to burn out; there are virtual connections, hook connections, and irregular wiring problems when wiring the socket; the electrical power is high, and the contact surface between wires and wires or wires and sockets is too small, resulting in high current and heating of the socket; the quality of the socket is relatively poor, plugging and unplugging several times, and poor contact between the plug and the socket will also cause the socket to heat up, etc.
Zhongke Testing provides accident identification services, which can identify the causes of socket fires, issue professional and reliable inspection reports, and assist courts and enterprises in resolving product quality disputes.

GB 2099.1-2021 Plugs and sockets for household and similar purposes Part 1: General requirements
GB 1002-2021 Single-phase plugs and sockets for household and similar purposes
GB 1003-2016 Three-phase plugs and sockets for household and similar purposes Types, basic parameters and dimensions
NB/T 10295-2019 Plugs and sockets for household and similar purposes Desktop sockets
GB/T 23307-2009 Ground sockets for household and similar purposes
GB/T 2099.2-2012 Plugs and sockets for household and similar purposes Part 2: Special requirements for appliance sockets
GB/T 2099.9-2017 Plugs and sockets for household and similar purposes Part 2-9: Special requirements for information sockets
NB/T 10474-2020 Plastic parts for sockets for household and similar purposes
GB/T 2099.5-2008 Plugs and sockets for household and similar purposes Part 2: Special requirements for fixed sockets with interlocking switches

A homeowner commissioned a decoration company to renovate the house, but a fire broke out not long after the house was delivered. According to the preliminary identification of the fire brigade, the source of the fire was an electrical outlet. In order to determine the cause of the fire, the court commissioned our company to conduct a technical appraisal of the power socket.
The expert team went to the site to conduct an investigation and at the same time inspected and identified the fire socket. At the same time, the following results were obtained:
1. The socket has incomplete quality marks and does not comply with GB 2099.1-1999 regulations;
2, the metal socket of the socket was found to have many gaps that were too large, and did not match the plug pins, resulting in excessive resistance during contact work, temperature rise, and arc flash discharge;
3, abnormal heat resistance and flame resistance tests comply with the requirements of GB 2099.1-1999, but it can be ignited and flames emit at high temperatures.