Extech 400A True RMS AC/DC Watt Clamp-On Meter

Extech 400A True RMS AC/DC Watt Clamp-On Meter


The Extech 400A True RMS AC/DC Watt Clamp-On Meter measures watts, curent, and voltage with AC/DC true power measurements of 240kW.


  • 0.9" (23mm) jaw opening
  • Fast 40 segment analog bargraph
  • Frequency measurements to 10kHz and true power measurements to 240kW
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The Extech 400A True RMS AC/DC Watt Clamp-On meter measures watts, current, and voltage to 240kW and frequency to 10kHz. A large 4000 count LCD display features a fast 40 segment analog bargraph. Other features include data hold, max/min recall, auto power off, and low battery indication to conserve battery life.

Notable Specifications:
  • AC power range: 40kW/ 240kW
  • AC power resolution: 10W/ 100W
  • AC power accuracy: ±(1.5% + 3d)@50/60Hz/ ±(1.5% + 3d)@50/60Hz
  • AC power input signal range: 0-250V, 0-400A, PF 0-1/ 0-600V, 0-400A, PF 0-1
  • DC power range: 40kW/240kA
  • DC power resolution: 10W/100W
  • DC power accuracy: ±(1.5% + 3d)/ ±(1.5% + 3d)
  • DC power input signal range: 0-250, 0-400A/ 1-600V, 0-400A
  • AC current range: 400A
  • AC current resolution: 0.1A
  • AC current accuracy: ±(1.5% + 3d)@50/60Hz
  • AC current input signal range: overload protection: 600A AC (AC frequency range 40Hz-1kHz)
  • DC current range: 400A
  • DC current resolutin: 0.1A
  • DC current accuracy: ±(1.5% + 3d)
  • DC current input signal range: overload protection: 600A DC
  • AC voltage range: 600V
  • AC voltage resolution: 0V
  • AC voltage accuracy: ±(1.5% + 2d)@50/60Hz
  • AC voltage input signal range: overload protection: 800V AC
  • DC voltage range: 400v
  • DC voltage resolution: 0.1V
  • DC voltage accuracy: ±(1.0% + 2d)
  • DC voltage input signal range: overload protection: 800V DC
  • Frequency range: 10kHz
  • Frequency resolution: 0.01-100Hz
  • Frequency accuracy: ±(0.8% + 2d)
  • Frequency input signal range: overload protection: 600V AC
  • Dimensions: 7.2 x 2.5x 1.4" (183 x 64 x 36mm)
  • Weight: 6.7oz (190g including batteries)
What's Included:
  • (1) Meter
  • (1) Set of test leads
  • (2) AA batteries
  • (1) Carrying case
Image Part # Product Description Price Stock Order
Extech 400A True RMS AC/DC Watt Clamp-On Meter 380940 400A true RMS AC/DC watt clamp-on meter
Drop ships from manufacturer
Extech 400A True RMS AC/DC Watt Clamp-On Meter 380940-NIST 400A True RMS AC/DC watt clamp-on meter, NIST traceable
Drop ships from manufacturer

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