Identification of electric shock accidents with power cord plugs

Electric shock is a common name for electric injury. It usually refers to the direct contact of the human body with the power supply or high-voltage electricity, and the current is transmitted through the air or other conductive media, causing tissue damage and dysfunction to the body.

The plug, as a key intermediary between electrical appliances and power supply, bears the important responsibility of transmitting electrical energy. Proper selection and use of plugs is essential to ensure the safe operation of electrical equipment. Improper use of mismatched or inferior plugs may cause current fluctuations, cause electrical failure, and even trigger an electric shock hazard in extreme cases.

Zhongke Testing and Appraisal Institute can provide power cord plug electric shock accident identification services, and make accurate identification of trace evidence analysis and accident cause analysis in various power cord plug electric shock accidents.

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socket electric shocks generally have the following causes:

1. Poor contact in the plug leads to leakage

If the neutral line and live wire of the plug are in poor contact, resistance will occur, which will lead to overloading of the wires, thereby causing leakage.

2. Electricity leakage due to aging of sockets

After being used for a period of time, the power socket will age, which can easily cause the neutral wire and ground wire to be short-circuited or have poor contact.

03. Current leakage caused by the fault of the electrical equipment itself

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2Plug leakage may also be caused by the failure of the electrical equipment itself, such as circuit board leakage, aging of insulation materials, failure of power supply capacitors, etc.

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A user purchased an xx brand storage-type electric water heater produced by a certain company in a shopping mall in xx city, and the shopping mall sent someone to install it. Later, due to poor contact, the mall sent someone to replace the plug of the water heater power cord. One afternoon, the user was unfortunately electrocuted while using the water heater.

Entrusted by the court, a third-party appraisal agency conducted a technical appraisal of the "power cord plug electric shock" to find the direct cause of the accident.

Identification and analysis results:

Identification personnel went to the scene of the incident to conduct an inspection. The analysis of the causes of the "power cord plug electric shock" involved in this incident is as follows:

(1) The grounding wire and the grounding pin in the power cord have been disconnected. The power cord and the electric water heater after the plug are equivalent to no grounding wires. When an electric shock occurs when the grounding wire behind the broken head is connected to the L pole plug, there is no residual current to the ground, so the power socket Level leakage protector does not operate;

0 (2) The grounding wire does not pass through the switching component of the leakage protector in the electric water heater power cord, but is directly connected to the shell of the electric water heater. When an electric shock accident occurs, the leakage protection in the electric water heater power cord There is no residual current in the circuit of the electric water heater, so the leakage protector does not operate. Even if it operates, it can only disconnect the L line and N line behind the leakage protector, but cannot disconnect the already charged yellow and green two-color wire (ground wire). In other words, a conductive line is bypassed between the electric water heater shell and the plug, bypassing the leakage protector.

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2 After inquiry and investigation, we learned that the plug was replaced by maintenance personnel in the second half of year

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