... I've posted the gist of this into uk.railway: lets see how they
respond to this. Sounds most peculiar seeing as the weather situation
was fairly 'bog-standard' and pantograph technology has been around for
... 100 years?

I posted the reason, which was given by our Fleet manager at East Ham EMUD
this morning, copied from my earlier post on UKr:
Well you know when your on a 357 and you occasionally hear a Pop sound, like
someone has knocked a bit of hollow plastic hard, or something hit the
train, well that Pop sound wasnt happenning and a build up short-circuited
certain Electrical Systems in the cupboard by the loo.
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