"Paul Taylor" wrote in message
news
On Fri, 27 Dec 2002 18:16:19 +0000, JennyC wrote:

1) There had obviously been a short circuit and when we
investigated saw
that the wires were sort of dried out (if that makes sense) and
frizzled
at the ends. Could this be due to the really hot temperatures in
the GH
during the summer months ?? If so what should we do to stop a
repeat of
the problem ?? (I do use shading but it still gets HOT)

A short circuit? If there had been a short circuit then a fuse or
circuit
breaker should have open circuited and turned off your electricity
supply
to your greenhouse before anything dangerous can happen.

Yes - the circuit breaker cut in, which meant the electricity was cut
of and therefore the temperature dropped to below freezing out there
:~((

Wires can heat up but if you have a correct fuse rating then this
safely
protects the wires from short/overloads and therefore cannot heat up
from
short or overload.

OH


Dried out and frizzled at the ends? However, where wire connects to
another piece of equipment then a bad connection certainly can
result in
very hot temperatures - so you need to make sure that all the
connections
are good.

Also, you want to keep water away from the electricity supply.

The wiring runs through the house wall and along a dry brick wall.


2) Is there special wire one should use?

Mains cable capable of carrying current to your lighting/heater.
Look at
the power rating of your lighting/heater - add up the current both
take
and ensure your cable can carry this easily.
Generally appliances only state a power rating rather than current.
For
example your lighting may be 60W (w stands for watts). With a 240V
mains
electricity supply (UK) the current taken by your lighting is 0.25
amps.
(Current in amps is calculated by dividing the rated watts by
the voltage (240 in the UK), 60 divided by 240 = 0.25A. Note that
some
appliances are rated in KW (kilowatts) where 1KW = 1000W.)
Get a current for your heating system. Add this to your lighting
current
to give you your total current - then make sure your wire can handle
this. Some common wire ratings are 3A, 6A and 10A.

I'll get the technical half to have a look at that tomorrow :~)

3) or special insulation ?

Must be suitable for mains use. Greenhouse temperatures won't be a
problem.

We used proper EU standard stuff !

If you don't know too much about electricity then you could always
get an
electrician to look at it from a safety point of view - he /(she)
would
be able to tell you if you need to do anything to ensure it is safe
in a
couple of minutes.
PT

Thanks PT
Jenny