The SDM230-Modbus is a single phase two module DIN rail meter with the following features: Measures kWh, Kvarh, KW, Kvar, KVA, PF, Hz, dmd, V, A, etc.; Bi-directional measurement IMP & EXP; Two pulse outputs; Modbus RS485; 35mm DIN rail mounting; 100A direct connection; Better than Class 1 / B accuracy.