1. All clamp meters can measure current through a single wire, if you put two wiresinto the clamp jaw, the reading will be zero, only from one wire, you will get exact digits. 2. Measure one wire in one time. If measure more than one wires in one time, the reading will be inaccurate. 3. When measuring current, to get more accurate readings, the ambient temperature must be 0 to 40℃.