Electrical accident hazard

Update date:2018-08-15 Source:MAXGE

In daily life, electrical accidents are often seen, and their harmfulness should not be underestimated. What are the electrical accidents and what are the hazards? rcbo


First, electric shock

1, divided into electric shock and electric injury two forms of injury.

2, electric shock current value: perceptual current (average male 1.1ma, female 0.7ma), get rid of current (average male 16ma, female 10.5ma), ventricular fibrillation current (about 50ma, related to duration). Human body impedance: about 1000~3000ω when dry, about 500~800ω when wet.

3, electric shock type:

According to whether the charged body touched during the electric shock is in normal charging state, it is divided into direct contact electric shock and indirect contact electric shock; according to the way the human body touches the charged body, it can be divided into three types: single-phase electric shock, two-phase electric shock and strid voltage electric shock. Single-phase electric shock accidents accounted for more than 70% of all electric shock accidents.

4. Electrical injury is the damage caused by the thermal, chemical and mechanical effects of current. Electrical injuries include electrical burns, electrocautery, skin metallization, mechanical damage, electro-optic ophthalmia and many other injuries. Electric burns. It is the most common electrical injury. Most electric shock accidents contain electrical burns. Electric burns can be divided into electric burns and arc burns.

Second, electrical fires and explosions

1. Electrical fire and explosion are fires and explosions caused by electrical ignition sources. Dangerous temperatures, sparks and arcs generated during operation of electrical installations are the primary form of electrical ignition sources. rccb

(1) Dangerous temperature: short circuit, overload, leakage, poor contact, overheating of the core, poor heat dissipation, mechanical failure, abnormal voltage, electric heating appliances and lighting equipment, electromagnetic radiation energy.

(2) Electric spark and arc: The electric spark is a breakdown discharge between electrodes, and the arc is a collection of a large number of electric sparks. Divided into working sparks and arcs, accident sparks and arcs.

2. Deflagration of electrical equipment and electrical circuits

Including oil-immersed transformer fire explosion, motor fire, cable fire and explosion.


Third, lightning hazards

1. Types of lightning, forms of damage and consequences of accidents

(1) Types of lightning: direct lightning strikes (each discharge process of direct lightning includes three stages: pilot discharge, main discharge, and residual light), lightning induction (including lightning electrostatic induction and lightning electromagnetic induction), and ball lightning.

(2) Harmful form of lightning

It has the characteristics of large lightning current amplitude, large lightning current steepness, strong impact and high impact overvoltage; it has three kinds of damage effects such as electrical properties, thermal properties and mechanical properties.

(3) Accidents of lightning hazards: fires and explosions, electric shocks, destruction of equipment and facilities, and large-scale power outages.

2. Lightning parameters: thunderstorm day, lightning current amplitude, lightning current steepness, lightning impulse overvoltage.

Fourth, static hazards

1. The form of electrostatic damage and the consequences of accidents

Causes explosions and fire accidents, may cause secondary accidents, and hinder production.

2, the characteristics of static electricity

(1) Generation of static electricity

Power-on mode (contact-separation electrification, breaking electrification, induction electrification, charge transfer), solid static electricity, human body static electricity (up to 10000 V or more), powder static electricity, liquid static electricity, vapor and gas static electricity.

(2) Dissipation of static electricity: neutralization and leakage.

(3) Influencing factors of static electricity: materials and impurities, industrial equipment and industrial parameters.


Fives  Radio frequency electromagnetic field hazard

Refers to electromagnetic waves with a frequency above 100khz. harm:

1. The body absorbs radiation energy and is subject to different degrees of damage.

2. The production of induced discharge causes the detonating device to be accidentally detonated.

Sixth, electrical equipment failure hazard

Category: open circuit, short circuit, abnormal grounding, leakage, misclosing, electrical equipment or electrical components damage.

Hazard: Fire and explosion, abnormal electrification, abnormal power outage, safety related system failure.

Copyright© 2017 www.maxge.com All Rights Reserved.

Copyright© 2017
www.maxge.com All Rights Reserved.







We won't share your info with third parties.