A new tool in the arsenal. I recently was doing some work with Leakage Current for medical equipment. The Hioki 3283 Clamp-on Leak Current meter was very useful. With a selectable high frequency filter, a MIN / MAX hold feature, a sufficiently wide jaw diameter, and 10 uA resolution, it was great to measure both ground currents as well as net currents across the phases and neutral. Highly recommended.

Kind of sad really. Read about it here. Best Power Technologies, of Necedah, WI was one of the early power quality success stories. I recall looking at one of their mid-80’s ferroresonant UPS that reminded me then (and now) of a guitar amplifier – electronics / controls up top, that big ferro-transformer in a separate enclosure down below. At the time, as an R&D engioneer for a competitor, we had our own small UPS models under development. And over the years I have specified, worked with, monitored, and otherwise run across dozens of these units. In my recent office move I threw out a folder full of manuals and installation instructions from old projects and old clients.

As is usually the way when large corporations buy out a smaller competitor, Best Power died a slow death through purchases by General Signal, then by PowerWare, which is now a subsidiary of Eaton Corporation. The Necedah plant, which once employed more than 1000 people, was down to 120 and only occupied 15% of its building at the time the closure was announced. Once can only imagine the impact that sort of gradual decline has on a local economy.

Not to say that Best Power’s ferro-based technologies were not going to die out eventually from obsolenscence. But long before APC was a UPS juggernaut, Best Power was one of the brightest stars in the industry, and its passing should be noted.