Purpose of earth fly leads on RCBO's

Gavin John Hyde · Sep 21, 2017

Been sent an email today telling me Hager have a new smaller rcbo range out and have done away with the earth fly lead which is good when doing a IR test. The new rcbos are a good fit for adding into existing CU's as they give you plenty of space on top for cables,

Which makes me wonder why is it some rcbos have the fly lead and other do not have the fly lead?

Anybody know why???

happysteve · Sep 21, 2017

Someone (Marvo, I think) posted a link with and RCBO teardown. They start discussing the RCD aspect around 12:54, and the key bit of info about the functional earth is at about 14:45. Seems to be a back-up in the event of losing the neutral (I think!)