Soft start, also known as slow start or anti-impact current protection IR function soft start function refers to the DC fan power, speed from zero slowly rise to rated speed, about 3 ~ 10 seconds; The current therefore rises slowly from zero to the rated current range. The function of soft start for large DC fan is that the inner stator of DC FAN is made up of coil and electric drive, the coil is inductive load. When the fan blade is running from static to full speed, the current flowing through the coil is very large (the inductance of the coil is equal to the pure current resistance of the coil at the moment of starting) , the impulse current is more than 3 ~ 5 times of the rated current If the rated current is about 1A, the impulse current will be over 3 ~ 5A. In this way, the customer's power shock capacity requirements are too high, for example, the selection of rated current 48V, 1A fan. 48V * 5A 240w or more. With soft-start DC fan, the current will not impact so high, the maximum current is equal to the rated current + 10% or so; for example: 48V 1A DC FAN, only 50W can be left over (of course, depending on the specific circumstances) . Compared with 240W power supply, 50W power supply has obvious difference in cost and occupied space. From this point of view, using the fan with soft start-up has advantages in overall cost and energy saving. In addition, the DC fan with soft start has low impulse current, less harm to the internal components of the DC fan, and safer performance. Shenzhen Dongxingyue Technology Co. , Ltd. has its own senior soft and hard engineer, designed out of the big DC fans have good soft start function.

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