... 0.00 V~600V, Active Power: 0.0W~12kW, RS232 inferface, Data Storage: 500 sets. .Technical Specification FunctionSimultaneous measurement ... keep data, " DH " symbol appearsData Storage500 setsRS232 InterfaceUSB-RS232 interface, download data to computer for analysis and managementAutomatic ShutdownAutomatic shutdown ... Application ETCR4400 Three Phase Digital Phase Meter ----Manufactory, RS232 interface