WT300E Digital Power Meter


This firmware is intended to upgrade the WT300E to the latest version.


Please read installation manual (IM B8212ZY-02EN) throughout before performing the installation.
Each zip file contains firmware program file and an installation manual.

Revision History

Version Release Date Content
1.04 Nov 26,2018
  • Support additional suffix code for power cords corresponding to Taiwanese RoHS.
1.03 Jun 8,2018
  • Changes with replacement parts.
1.02 Nov 4,2016
  • Fixed the problem that the WT300E with the Ethernet I/F option (/C7) sometimes hung after operating for one and a half months continuously.
  • Fixed the problem that when the over current protection function went into action during auto range integration on the WT310E, sometimes a measurement value after that was not updated.



Please read Software Agreement carefully before downloading.


Version 1.04
Release Date Jun 30, 2020
File Name WT300E_104.zip 2.5 MB


Type Firmware* Registration is required to download.


* Software Agreement
  • The property rights, proprietary rights, intellectual property rights, and all other rights associated with the software are held by Yokogawa Test & Measurement Corporation.
  • Under no circumstances is any dumping, reverse compiling, reverse assembly, reverse engineering, or any other kind of alteration or revision of this software allowed.
  • This software is offered free of charge, but no unlimited warranties are made against any defects whatsoever.
  • Also, Yokogawa may not be able to accept inquiries regarding repair of defects in or questions about this software.
  • The contents of this software are subject to change without prior notice as a result of continuing improvements to the software's performance and functions.
  • Yokogawa bears no liability for any problems that may occur during download or installation of this software.
  • Use of the Yokogawa Web site is at the user's own risk.
  • Any parties contributing to the creation or distribution of the contents on the Yokogawa Web site shall bear no responsibility whatsoever for any damages occurring as a result of the use of said contents.
  • Note that you must agree to the contents of “Software License” for the software that encloses or displays the “Software License” as the conditions of use.
  • This software product may contain open source software (hereafter referred to as OSS). License terms appropriate for each OSS component are applicable in place of the terms of this license. If there is a discrepancy between the terms of the OSS license and the terms of this license, the license terms of the corresponding OSS take precedence.

Downloading of the software indicates acceptance of the software agreement.

Related Products & Solutions

WT300E - Economy

  • Standby Power Measurements, Energy Star®, SPEC Power® and IEC62301/EN50564
  • Evaluation and Testing of Batteries, Home Appliances and Uninterruptible Power Supplies (UPS)