... and displays real time AC phase voltage, line voltage, and current with LED display in 3P3W or 3P4W network. It is ... , voltage input, 4 bits display + one RS485,YD9122:3 phase current, voltage input, 4 bits display + one relay contact output,YD912A:3 ... phase current, voltage input, 4 bits display +one RS485 + one passive contact input + one relay contact output.PerformanceStandard compliance: GB/T ...