Fluke 437 ii mains analyser fluke fluke 437 ii the fluke 437 ii mains analyser helps to locate predict prevent and troubleshoot power quality issues in three phase and single phase power distribution systems fluke s patented unified power measurement energy loss algorithm measures and quantifies energy losses due to harmonics and unbalance issues this allows the user to pinpoint the origin of energy waste within a system and give it a monetary value the 437 will display ten power qualit