On 1 Nov, 18:46, John B wrote:
Haven't got a cite to be honest - it's something I've picked up here
and from the Wiki (so it might be rubbish - but it is certainly true
that all DC EMUs post-465s are readily AC-able).

I've definitely seen the same thing (eg The Class 444 article says
"Like all new build third rail stock in the UK, one coach in each unit
is fitted with a recess for a pantograph"), which implies a rule, but
really is just stating the facts on the ground.

(There is a rule that all new electrification has to be AC overhead -
both as a standardisation guideline and a health and safety rule -
which may be where the confusion comes from)

U

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