BACKGROUND
Please see attachment.

ACTION
IEC National Committees are invited to approve and comments on:
• the proposed withdrawal of IEC 61400-25-6
• inclusion of 6.3 Wind turbine condition monitoring logical node WCON from IEC 61400-25-6 into the
future IEC 61400-25-2 Ed 3
• inclusion of 8.2 Attributes for condition monitoring measurement description from IEC 61400-25-6 into
the future IEC TS 61400-25-71 Ed 2

P-members are kindly invited to nominate experts to JWG 25, and the appointed experts should be entered
into the IEC Expert Management System (see documents AC/21/2004 and AC/24/2008) by 2019-10-11.

IEC national committees are invited to consult both IEC TC 88 and IEC TC 57 delegates when developing
their national positions. Work on the Condition Monitoring update will be initiated in a one-day workshop in
Copenhagen starting Monday October 14th, 2019.

NOTE: Final decision to reduce scope of condition monitoring within the IEC 61400-25 series as described
here is not taken. Should sufficient expertise be nominated the update of all functionality in a new edition of
IEC 61400-25-6 will be considered.

NOTE: US TAG ballots must be submitted prior to the IEC deadline to allow for resolution of any comments.
Please request commenting forms from the TAG Secretary (secretary@aresca.us)