... power factor, frequency, active energy, reactive energy. - Current and voltage ratios set freely. - Up to 3 alarm relays, contact capacity: AC 250V ... systems for auto control, e. g.: single/three phase current/voltage/power consumption...etc for displaying and control.2. Ordering Code:Model ... to contact us ! IBEST ELECTRICAL CO.LTD IBEST DW8 Single Phase Series , Up to 3 Alarms , Digital Coulo Meter