Chip wrote:

I meant to stay out of this thread, however, something similar has
happened to me while using a hedgetrimmer with a ~50m x 0.75mm sq
flex, this being one occasion when such a length is unavoidable in
large gardens. Unless we install several outdoor sockets, and this

You can reduce the risk by using a short(ish) thin flex on the tool, and
a heavy gauge extension lead.

thread really *doesn't* need to get onto outdoor electrics, ring or
radial g. Cut through the flex part way such that it was jammed in
the blades, evidently the short wasn't _short enough_ to blow the 5A
plug fuse. Ended up throwing the hedgetrimmer away from me and running
to pull the plug, which was hot. Even with the blade of the

Given time it would probably open the fuse... ;-)

hedgetrimmer + sparking flex in contact with wet grass, the RCD hadn't
tripped either.

Was it a double isolated tool? (i.e. 2 core flex). If so then there is
no reason why the RCD would trip since it looks for an imbalance between
feed and return, not an over currentfault.

This is one occasion where the 'circuit breaker plug'
proposed elsewhere in this fine thread would be a sensible addition.

Why? A circuit breaker in the same circumstances may behave in the same
way. When the fault current is not high enough to reach the
instantaneous part of its trip response (i.e. the solenoid operated
bit), it behaves as a thermal trip device (as does a fuse).

Possibly with 'arc fault' sensing ability, as now mandated in the US
for bedroom circuits (unlike the US however, we should wait till the
technology is through its teething problems before requiring its use).

Na, you need a more powerful trimmer so it can cut through the lead
cleanly ;-)


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/