This device can measure current and voltage values and frequency of line on three phase systems. The detective multimeter was designed to sense, detect and inform impending mechanical and electrical failures in three phase motors. Modern detective multimeter technology with the capability of fault detection at early stage provides excellently reliable system monitoring advantages, a remarkable productivity of quality production, minimized maintenance and repair costs and extended life of machinery and equipment in use. The measured min/max current values are saved in memory and can be displayed by request. Moreover the device features adjustable over/under current and voltage protection limits with adjustable time delay settings prior to producing contact output for alert. The multimeter compares the stored values with the momentary values and switches on the alarm levels gradually according to deviation. The alarm output is a potential free changeover relay contact output what can work by voltage or current failure. Programming of the relay output allows for definition of the alarm level at which the relay shall react in case of abnormal current or voltage. The connection for power supply and metering is available trough pluggable terminations on the back side of device. The three digit LED displays are giving information from momentary metered values. A LED lamp signs the selected value. The current transformer (CT) ratio is also selectable with front panel pushbuttons.