A car inverter is a device that can convert 12V or 24V DC energy from a car battery into 220V or 110V AC power, which is the same as the grid power for household appliances. With the car inverter, you can connect the cigarette lighter or car storage batteries to run the electronics, appliances, or various tools, which can greatly broaden the range of entertainment and work in the car. How to choose the right inverter for your car? Then, let's move on.
How to select a car power inverter correctly?
Which power rating is the best choice for a car inverter?
According to the required load range, almost all car electrical products are marked with the required power. For instance, the car refrigerator is marked with 150W, and the power of a suitable inverter should be more than 150W. If multiple electric loads are used simultaneously in the vehicle, we need to add all the power of the loads together, and then choose a car inverter with greater power than the total power.
Which type of car inverters is better, modified sine wave or pure sine wave?
Pure sine wave power inverter can provide high-quality AC power which is the same as grid power and drives any kind of load, but it requires high technical requirements and costs. However, a modified sine wave power inverter can meet most of our electricity demands with high efficiency, low noise, and favorable prices. Therefore, modified sine wave car inverters are the mainstream products in the market. By the way, modified sine wave power inverters should avoid inductive load. Generally speaking, the inductive load refers to high-power electrical products produced by the principle of electromagnetic induction, such as motors, compressors, and so on, which require a much larger start-up current (about 5-7 times) than the current required to maintain normal operation. In short, if you need electrical equipment with a large current start-up, a pure sine wave inverter is your best choice.
What is continuous power? What is peak power?
The power marked on car inverters includes continuous power and peak power. Among them, continuous power refers to the actual power of car inverters, also known as rated power, while peak power refers to the start-up power that inverters can provide in an instant to start the load of electrical equipment. Therefore, it should be noted clearly what the continuous power of the car inverter is when purchasing it, to avoid damage to the equipment.
Conversion efficiency of car inverters
As a very important index of car inverters, the higher conversion efficiency, the longer battery life, and the less heat generated by car inverters. Conversion efficiency is the ratio of output watt to input watt, the closer this number is to 1, the better its efficiency is. In general, the efficiency of inverters is more than 80%-90%, that is, input 100W and output 80W-90W, so the inverter itself consumes nearly 10W-20W of power. Conversion efficiency can be divided into no-load and full-load. Without load, the components in the inverter operate at the lowest power, which can generally be as high as 90%. However, it can be considered a good inverter with a conversion efficiency as high as 85% at full load. Therefore, car owners can simply judge the conversion efficiency from the heat of inverters by high-power load. The greater heat, the greater the energy loss, and the lower the conversion efficiency.
Intelligent protection function of car inverters
A good car power inverter should have a perfect protection function, which can protect your favorite car and power supply in all circumstances. Meanwhile, it should also have a sound and light alarm function to remind you to deal with various situations in time. In general, protection functions include input under-voltage (low voltage) protection, over-voltage (high voltage) protection, over-temperature protection, overload protection, over-current protection, and short-circuit protection. What's more, some car inverters provide LED displays, to show the battery voltage, output voltage, frequency, and current. Therefore, car owners can timely understand the running conditions.
Shell material and heat dissipation of car inverters
Low-power (less than 150W) inverters on the market are made of aluminum alloy and PP fire-resistant plastics, because PP fire-resistant plastics can withstand high temperatures over 150℃ without deformation. For 150W power and more, if no inferior components are used in car inverters, it is theoretically unnecessary to use fans but natural cooling for heat dissipation. Many low-power car inverters on the market are equipped with fans to dissipate heat actively. Normally, the cooling fans in car inverters are intelligent, which will start only when the inverters are loaded with electricity and reach a certain temperature.
Input and output interfaces of car inverters
Generally, there are two ways of connections to get power in car inverters: for a power rating less than 200W, the car inverters can be plugged into the car cigarette lighter, for a power higher than 200W, the car inverter is directly connected to the car storage battery by wire. Car inverters are usually equipped with an AC socket, USB charging port, cigarette lighter interface, and 5V-12VDC interface, and the more types and number of interfaces provided, the higher the cost-performance ratio is.
So, what power of an inverter is suitable for a car? Since there is a maximum allowable current in the design of a car circuit, the maximum output power of most cars through the cigarette lighter interface is generally not more than 200W. It is recommended that the input power of car inverters through the cigarette lighter interface is not more than 200W. If you need to use high-power electrical equipment, you need to buy an inverter that can connect to the storage battery. Moreover, the car engine must be started when the high-power inverters are working. Most of the car's built-in generators generate less than 1000W power. For the car inverters with more than 1000W power, if inverters work for a long time, it will cause the battery to lose power, because the power consumption is higher than the charging speed of the car generators for the batteries. If you often do it like this, you’d better replace your car’s own generator with a larger one.
In a word, an excellent car inverter should meet the following four requirements:
- Good ventilation, heat dissipation, workmanship, and electronic components.
- Provide enough power output interfaces and types of interfaces.
- High conversion efficiency and clear product power identification.
- Provide all kinds of intelligent protections.
