Hioki 3281 [3281] 600V / 600A AC True-RMS Digital Clamp Meter

The previous AC Clamp Meter CM3289 (⌀33 mm, rating of 1000 A AC) featured a low-profile design that was engineered to enable users to clamp around wires easier. The new instruments build on that product’s design by increasing both the jaw diameter (⌀46 mm) and the current capacity (by increasing the rating to 2000 A AC). Both new models preserve the CM3289’s ease of use so that thick cables (paired wires, etc.)1 are easily measured.

Hioki has redesigned the jaw (sensor) profile as part of an effort to expand its clamp meter line with models that are easier than ever to clamp around wires. The newly designed clamp meters have won broad praise, including an honorable mention in the 58th Product Competition at Electrical Construction Equipment and Materials (JECA) Fair 20192 and a 2019 Good Design Award3.

Although Hioki has recently updated many of its clamp meters, up until now only one low-profile model has been capable of measuring thick cables (paired wires, etc.). To address this issue, Hioki developed the CM3281 (mean value rectification method) and CM3291 (true RMS method) to enlarge the 33 mm diameter and 1000 A AC current rating of the AC Clamp Meter CM3289 to 46 mm and 2000 A AC, respectively.