How to deal with electrical fires - Solutions - Huaqiang Electronic Network

Probe domestic switch needle KG-300K, with a head diameter of 3.0mm, normally open switch needle

100V, 250mA, surface mount, high-speed switching diode

Single-chip microcontroller STM32L151CCU6

Photocoupler

(1) Power off the fire. When an electrical device catches fire or ignites nearby flammable materials, it is essential to turn off the power first. In indoor electrical fires, the main switch should be cut as soon as possible, and appropriate fire extinguishing equipment should be used immediately to control the fire. If the outdoor high-voltage transmission line catches fire, contact the substation or power supply station promptly to shut down the electricity.

Important precautions when cutting off the power: 1. Choose the correct position for the power source to avoid any interruption during the power-off process. 2. Ensure the power source is located near the support in the direction of the power flow to prevent wires from falling to the ground, causing short circuits or electric shocks. 3. Cut the live and neutral wires at different points to avoid generating a voltage segment. 4. When using a pull-switch, always use an insulated lever or rubber gloves. Due to smoke in the electrical room, the insulation strength of the knife switch may decrease, and wet hands or sweat during firefighting can increase the risk of electric shock. 5. Turn off the motor and magnetic switch. When using a load device, power off the motor via a button first, then cut the switch to avoid arc injuries caused by the load.

(2) Firefighting while the power is on. Live firefighting refers to fighting fires while the power remains active. This situation is usually very dangerous. Waiting for the power to be cut off before saving could result in losing the chance to act and worsening the danger. In cases where cutting off the power would severely affect production or safety, it might be necessary to quickly control the fire with minimal damage. However, this must be done safely for the firefighters.

Precautions for live firefighting: 1. Do not use conductive fire extinguishers such as water jets or foam extinguishers. Instead, use non-conductive options like carbon dioxide, 1211, dry powder, or tetrachloroethylene extinguishers. These have good insulation properties and are suitable for most electrical fires, but their range is limited, so firefighters should not stand too far away. In addition to wearing fire-resistant gear, firefighters should also wear insulated gloves and boots to avoid electric shocks. Only in special circumstances, firefighters should use specialized equipment after taking proper protective measures. 2. Be aware of the surroundings and avoid direct contact between the body or firefighting tools (like fire hooks or axes) and live parts. Especially for high-voltage lines, keep a safe distance to prevent electric shocks. Also, be cautious of step voltage if a live wire falls to the ground; in such cases, insulated boots must be worn. 3. For oil-filled electrical equipment like transformers or oil switches, use dry sand to cover the flames. If the fire is outside the container and the equipment is undamaged, use COâ‚‚, 1211, or dry powder extinguishers from a safe distance of at least 2 meters. If the fire is large and threatens nearby equipment, cut off the power and use a large amount of foam extinguishing agent. Collect spilled oil into an accident oil tank or use oil-repellent facilities to prevent spreading. Avoid oil igniting in cable trenches. 4. For rotating electrical equipment, spray water evenly to cool it and prevent deformation. COâ‚‚, 1211, or dry powder extinguishers can also be used, but never use sand, as it can damage internal components and cause serious issues.