Frequency meter CE, ISO9001 Two alarm outputs Programmable Four digital inputs Frquency meter1.Applied in power networks and power auto- ... .RS-485, MODBUS-RTU protocol, realize remote communication;4.Four digital inputs to monitor and control the switch state;5.Two ... bits LCD/ LED Display Frequency40-60Hz, 0.2 class accuracy Digital Input4 digital inputs ,passive dry contact node, R<500Ω turn-on ...