Safety issues to consider in inverter design
1. Products with metal casing must be selected: Vehicle-mounted inverters generate large amounts of heat due to their large power. If the internal heat cannot be dissipated in time, the life of the components will be affected at best, and there is a risk of fire at worst. The metal shell has good heat dissipation properties on the one hand and will not burn on the other hand. It is best not to use products with plastic shells. In order to save costs, some products on the market use plastic casings for 150W or even 175W products. Even if a fan is added to help dissipate heat, such a product is not recommended because the fan increases the noise during use and affects the comfort of use. Second, the working life is generally short, which reduces the reliability of the entire machine. If it stops running one day, the consequences will be serious.

2. For driving safety, be sure to choose split products instead of integrated products: there are four disadvantages of the integrated inverter. First, because the car cigarette lighter socket is not very deep, the weight of the integrated inverter is concentrated at the rear. The bumps during driving of the car can easily shake off the inverter or cause poor contact of the plug. Second, the integrated inverter is plugged into the cigarette lighter socket, and the rear part is exposed for a long time. When electrical appliances are plugged in, the exposed part will be longer, which will affect the shifting operation of the right hand. This is closely related to driving safety. Wan pay attention. Third, since it is directly plugged into the cigarette lighter socket, the rear row of the integrated inverter cannot be used and can only be extended with a power strip. Fourth, the integrated casing is made of plastic. Everyone knows that plastic is not resistant to high temperatures. Therefore, if a large current passes through the part where the integrated inverter contacts the cigarette lighter socket, it will generate high temperatures, causing the head of the integrated inverter to deform. Or melt, or even cause a fire. For the above reasons, no matter from the perspective of safety or convenience of use, an integrated inverter cannot be used, but a split-type inverter with a metal shell should be selected.

3. Inverters with power above 150W must be equipped with battery clamp wires: car cigarette lighter fuses are generally 15A and are only suitable for use with electrical appliances with a rated power below 150W. If it exceeds 150W, you must use a battery clamp cable to draw power directly from the battery, otherwise the car wiring and fuse will be burned out.

4. Choose a product whose output waveform is a sine wave or simulated sine wave: the rising edge and falling edge of the output waveform of a product with pure square wave output are very steep, and its positive maximum value to negative maximum value are generated almost at the same time. In this way, for The load and the inverter itself cause severe instability effects. At the same time, its load capacity is poor and it cannot carry inductive loads. If the load is too large, the third harmonic component contained in the square wave current will increase the capacitive current flowing into the load, and in severe cases will damage the power supply filter capacitor of the load.

5. It must have over-temperature alarm and over-temperature protection functions: When using high-power electrical appliances, the inverter will generate a lot of heat. If the temperature is too high, firstly, it will affect the normal service life of the inverter, and secondly, there will be a risk of fire. . Third, if you touch it without knowing it, you will burn your hands. The inverter with over-temperature protection function can emit a buzzer alarm and automatically stop working and cut off the output when the temperature rises to about 70 degrees, thus protecting the safety of the inverter itself and the safety of the people in the vehicle.
6. The input must have under-voltage protection: Many times the inverter is used in a parking state and has an input under-voltage protection function. When the battery voltage reaches a certain level, a buzzer alarm will sound to remind the user to turn off the appliance. When it reaches a certain level, it will automatically stop working, thus preventing the battery from over-discharging and causing the embarrassment of being unable to start the car.

7. Input overvoltage protection, output overload protection, and output short-circuit protection are also essential to protect the safety of the inverter itself.