... fluctuation Purify fuction solve the Power grid and the power source pollutionDetailed Product Description:Home ... ,8) 4 steps AVR, 220v+_10%, three steps to increase the voltage, one step ... transfer efficiency up to 90% .( use copper transformer , but price will be higher than normal ... certificate,CE certificate and ISO9001 Certificate,13) Small no-load current ,<=450ma14) Short transfer time ,<=4ms,15 ...