In order to understand the layman, I will say it plainly: The excellent inverter must have the following points: the waveform is as close as possible to the sine wave (waveform distortion), the frequency is stable at 50HZ, and the short-time overload capability is strong (output power factor), protection Complete measures, high inverter efficiency (output power factor), small external electromagnetic interference (input power factor), large input voltage redundancy (input voltage range), and so on. According to the technology used, the inverter is divided into a power frequency machine (also called a low frequency machine) and a high frequency machine. The power frequency machine has a simple structure, a strong load capacity, and a low failure rate, but the weight is large and the efficiency is low (the power frequency machine is generally Both are sine waves); high frequency machines are the opposite. However, with the improvement of technology, the high-frequency machine has been continuously improved to overcome some of its own shortcomings, which is the development direction! Pay attention to the following points when purchasing: 1 Determination of power size: generally take 130% of the total power of the required electrical appliances as reference. It is too big, because the inverter is generally the most efficient at full load, and the long-term low-load work efficiency is too high. Low, and wasted high-powered acquisition costs. However, it should be noted that if there is a high-power motor-like inductive load in your load (such as ordinary air conditioners and refrigerators), the power of the inverter will increase accordingly due to the instantaneous power of the motor starting several times the rated power. Several times, such as an air conditioner used to drive a maximum electric power of 1200W, you should prepare an inverter of at least 3000W. (Special attention: the power W and the professional term VA are not the same thing, that is, 1KW is not equal to 1000VA. Professionally, the inverter power should be calibrated with VA, and W is not accurate. For most 12V to 220V inverters now, 1000VA is equivalent to 700W.) Type 2 determination: If the load type is pure resistance (such as incandescent lamp, electric furnace, electric blanket, electric water heater, water heater Etc.) only need a cheap square wave or other non-sinusoidal inverter; if the load type is pure inductance (such as electric fan, electric drill, old fluorescent lamp, range hood, etc.), Then you must buy a sine wave inverter, although some times you can use the modified sine wave temporarily, but the efficiency is very low, the appliance is easy to heat, and the damage to the load is very large, it is not a last resort, it is recommended not to use, other The type of inverter is absolutely forbidden (for example, if you plug the fan into the square wave inverter, you will find that the fan is buzzing, but it does not rotate, sometimes it can rotate, but the speed is very slow, use How long will your fans to smoke!). For mixed liabilities (that is, inductive liabilities and resistance loads), such as rotatable roasting stoves, spotlights with electronic rectifiers, heating and cooling air conditioners, automatic soymilk machines, etc. are typical mixed liabilities because they A sine wave inverter must also be used if there is an electric motor inside and a heating element. 3 brand choice: this can not be generalized, but the brand name will give people a sense of trust, generally heavy weight, workmanship is more assured. It is recommended to use domestic brands. Many imported brands are fakes! 4 Other precautions: The smaller the noise at work, the better. The higher the efficiency, the better. The smaller the interference to the outside world, the better. Remember the following relationships, which are good for purchase: Price: sine wave > modified sine wave > square wave Performance: sine wave > modified sine wave > square wave Scope: sine wave > modified sine wave > square wave The following is a quality Inverter parameters, you can produce test output power capacity 2100 watts / 3000 VA maximum configurable power 2100 watts / 3000 VA rated output voltage 230V full load efficiency 91.00% output voltage distortion is less than 3% output frequency 50Hz + /- 3 Hz Crest Factor 3:01 Waveform Type Sine Wave Input Voltage: 12V Control Panel LED Status display with load and battery bar graph and "Battery On", "Replace Battery", "Overload" indicators. Audible alarm: Special low battery alarm emergency shutdown Yes Surge protection and filtering Surge suppression energy 420 Joule filter Multi-stage noise filter in accordance with UL1449 environment Operating environment 0 - 40 °C Operating relative humidity 0 - 95% Operation Height 0-3000 meters Storage temperature -15 Storage relative humidity 0 - 95% Storage height 0-15000 meters Audible noise 4mm from the surface of the device 15.00 dBA Online heat dissipation 655.00 BTU/hr Conformity Management agency certification C-tick, CE , EN 50091-1, EN 50091-2, EN 55022 Class A, EN 60950, EN 61000-3-2, GOST, VDE Standard warranty 2 years repair or replacement, on-site service, available extended internal authorization optional Environmental requirements Compliance with RoHS 7b Exemption, China RoHS