The SureTest family of circuit analyzers are claimed to be the first handheld circuit analyzers capable of applying a full 15A load without causing interruption to equipment on the circuit. Optimized to identify a wide range of problems common to electrical circuits, all four models in the family identify and locate loose power connection, bad splices or receptacles, loose ground connections and high-resistance grounds as well as verify proper wiring and test GFCI receptacles and line voltage and voltage drop. Certain models verify isolated grounds and dedicated circuits, plus measure line voltage drop, neutral-to-ground voltage, ground impedance, and the estimated load on the branch. An industrial model is available for environments where variable speed drives, switching power supplies, or lighting could potentially damage sensitive equipment. In addition to standard circuit analysis, the industrial model also captures true rms measurements, analyzes power measurements, and measures harmonic distortion to the 31 st harmonic.