... weight,High efficiency; 3.100% full-load burning test; switching power supply -----Manufacturer in Liushi for 8years, ISO 9001:2008 ... / Over load LED indicator for powr on Fixed switching frequency at 37KHz Cooling by free air convection 1 year ... 2G 10min./1cycl, period for 60 min, each along X, Y, Z, axes 5.SAFETY Withstand Voltage I/P ... Rise,Hold Time200ms,100ms,30ms at full load switching power supply