Hi all.

At my house, we have some outside floodlights ( 3*500 w halogen ) which were
obviously retro-fitted by the previous owner.

These have been added to an existing lighting circuit with the obvious
result that the breaker must have been tripping.

I was looking at the CU today, and I see that the other lighting ccts are
5A, but this one has had a 20A breaker installed!

I intend to correct this now I've noticed!

There's a spare way on the CU I can use for a dedicated circuit, that's no
problem.
However, the switch for the floodlights is a double switch, with one switch
operating some internal lights ( and 2-way at that ), the other operating
the rogue floodlights.

Is it permitted to have a dual light switch fed from seperate circuits?
It might lead to someone incorrectly assuming that the switch was isolated
when only 1 cct was isolated, was my concern.

--
Ron

In article ,
"Ron Lowe" writes:

Is it permitted to have a dual light switch fed from seperate circuits?

Yes. It's quite common with the landing light switch which
is often combined with a downstairs light on a different
circuit. You must keep the two circuits electrically separate
(no sharing of neutrals, etc, although cross-connecting earths
is OK).

It might lead to someone incorrectly assuming that the switch was isolated
when only 1 cct was isolated, was my concern.

It might, but people shouldn't be making any such assumption.

The floodlamps could go on a 10A circuit. However, you might
want to consider fitting lower power bulbs -- 500W is usually
way OTT outside at night in a domestic situation. If they are
left on for any time, find some energy saving IR-reflecting
coated bulbs. The GE ones are rated 375W (500W equiv) and 225W
(300W equiv). B&Q have them sometimes, but not always.

--
Andrew Gabriel

In article ,
Ron Lowe wrote:
Is it permitted to have a dual light switch fed from seperate circuits?

Yes. Upstairs and downstairs hall lights is the common one.

It might lead to someone incorrectly assuming that the switch was
isolated when only 1 cct was isolated, was my concern.

Never, ever, *ever* assume something like that is isolated. Test always.

--
*No radio - Already stolen.

Dave Plowman London SW
To e-mail, change noise into sound.

In message , "Dave Plowman (News)"
writes
Never, ever, *ever* assume something like that is isolated. Test always.


A bit like the light switch in a friend of mines lounge that I looked at
today. The complaint was that the lights in the conservatory, which her
son uses as a bedroom, were not working.
The switch which is in the lounge, part of the original house, did not
have any power to it, the bulb in one of the lights was physically
broken and shorted out. I removed the bulb and went to find why there
was no power. Trips all OK, checked before hand and none had tripped
out. Eventually found a fused spur on the upstairs power ring with a
blown 3A fuse that fed the conservatory lights. Replaced it and all was
well.
The slightly worrying thing was that although this is apparently a
common practice the light switch appeared part of the lounge and did not
look like an addition although it must have been. My thought is some one
turning off the downstairs lighting circuit and then working on the
conservatory lights could have a rude awakening.

As Dave said "never assume" "Test always"
--
Bill

Andrew Gabriel wrote:
You must keep the two circuits electrically separate
(no sharing of neutrals, etc, although cross-connecting earths
is OK).



Is there a specific technical reason/regulation for this (apart from
that vague term "Good Practice")?
I would have thought that if the cable IR drop and maximum current
criteria were met, then there would be no reason against doing so.

CRB

In article . com,
crb wrote:
Andrew Gabriel wrote:
You must keep the two circuits electrically separate
(no sharing of neutrals, etc, although cross-connecting earths
is OK).



Is there a specific technical reason/regulation for this (apart from
that vague term "Good Practice")?
I would have thought that if the cable IR drop and maximum current
criteria were met, then there would be no reason against doing so.

The obvious one is RCD protected circuits. Apart from the very real safety
issues when doing maintenance.

--
*I was once a millionaire but my mom gave away my baseball cards

Dave Plowman London SW
To e-mail, change noise into sound.