Switching power supply has been used in various field applications all over the world. Depending on type of product, input source of either alternating current (AC) or direct current (DC) is acceptable. Prior to operation of the power supply, users should confirm the following: the type of input voltage (AC or DC), the range of input voltage, and other conditions written on specification sheet. Input voltage exceeding the operating range would cause damage to the power supply. Also, input voltage with distorted waveform, even within the operating range, could also lead to malfunction of the power supply.
(1) If input voltage is of DC or square wave, its maximum value should be equal to 1.4 (√2) times of the peak value of sine wave. For example, input voltage of 85~264VAC can be replaced with DC voltage of 120~370V.
(2) Input source of DC or square wave is not acceptable for S.P.S. with function of input voltage auto-selection.
(3) Input Frequency:
The frequency of AC mains for S.P.S. is generally 50Hz or 60Hz. Taking into account deviation of ±3Hz from power plants, S.P.S. is designed to accept input frequency within the range of 47~63Hz. For special applications, such as for boats or ships, the frequency of 440Hz is acceptable, but users should be aware of the increased leakage current.
(4) The input range for products with safety approvals is available on model labels of the casings.