The Hioki PD325910SP Non-Contact Digital Phase Detector features non-contact voltage detection and measurement technology that prioritizes efficiency and safety, protecting customers that need to conduct on-site electrical work as part of renovations and expansions of manufacturing plants and buildings. The PD3259-10SP model allows you to check both phase order and line voltages simply by clipping the sensors to the outside of the circuit's insulated wires. The no-metal-contact measurement ensures maximum safety. Phase order, ground phase, and 3-phase voltage values are displayed at the same time on a large, easy-to-see display that can be used as-is to create photographs to document electrical installations. The PD3259-10SP indicates phase order (normal/reversed) judgment results via the color of its backlight and a beeping sound.