The HT7051 model was designed to perform professional insulation resistance measurements with test voltage programmable up to 5kVDC and wide measurement range up to 10Tohm which permits a large applications for each industrial LV environment. Three different function modes are available on the meter: FIX mode (fixed test voltage), ADJUST mode (programmable test voltage) and RAMP mode (programmable test voltage and duration time with up to 3 kind of selectable ramps) which permits to reach correct results in each situation. The Polarization Index (P.I) and Dielectric Absorption Ratio (D.A.R) available features are duration tests which permits to define a good behaviour of the global insulation. HT7051 meter is powered by a NiMH rechargeable battery with integrated adapter which permits to reach great performances during the measurements, it have a internal memory for saving results and a RS-232 interface for connection to PC and transfer saved measurements. All structure is fitted in a portable hard carrying case which assure safety typical of a “on field” meter.