How to determine the quality of the inverter

Since the inverter has been increasing use, but when people do not know how to buy an inverter to judge the quality of the inverter, here are a few points to attention:
First, instead of using a modified sine wave inverter 5000w solar inverter, since the modified sine wave inverter circuit is relatively simple, cost is low, but modified sine wave inverter with a carrying capacity was poor, small range, especially such as motors, printers, pumps and the like, it is easy to damage, this kind of judgment is very simple, that price is less than 1 yuan / W is likely to be modified sine wave inverter;
Second, are the sine wave inverter, and some manufacturers subtractive process, but also caused decline in the quality of the inverter, such as internal circuit boards must be moisture treatment; housing must meet certain thickness; noise during operation; overload, short circuit protection and alarm ; over-temperature protection; and meticulous self-repair aging and so on.
Third, no matter for what areas of the inverter, are automotive, shipbuilding, telecommunications, electricity, or home, is a very strict, very demanding production process.