I would like to connect a halogen up lighter with a dimmer control to a
lighting circuit. However, the up lighter has a 500W bulb (yes I know
this is expensive to run!) and I am concerned about the load on the
lighting circuit.

The rating info on the dimmer switch has two sets of figures with one
set, I assume, referring to the min and max wattage of the bulb stated
as 60-500W. The other set refers to 60-300W which I assume refers to
the rating of the dimmer control itself.

If this is right this would explain why the light came with a 5A fused
plug, because if the load of the whole light fitting was based just on
the bulb rating then the max load would be 2.1A (500/240) and surely a
3A fuse would have been sufficient.

However, if the dimmer switch is rated at 300W then the max load of the
light would increase to 800W (3.3A).

The lighting circuit currently has a max load of 400W (1.6A) and
therefore installing the light still leave a total max load of under
5A. As this is protected by a 6A circuit breaker would this be OK.

If this is OK is there any problem with the light not having the
protection of its own separate 5A fuse as I would cut off the plug and
wire is directly into the circuit.

The switch for the light would be a standard wall switch and am I
also correct in thinking that these switches are rated at 5A.

Any comment gratefully received.

Thanks for your reply.

Owain wrote:
geoffr wrote:
I would like to connect a halogen up lighter with a dimmer control to a
lighting circuit. However, the up lighter has a 500W bulb (yes I know
this is expensive to run!) and I am concerned about the load on the
lighting circuit.
The rating info on the dimmer switch has two sets of figures with one
set, I assume, referring to the min and max wattage of the bulb stated
as 60-500W. The other set refers to 60-300W which I assume refers to
the rating of the dimmer control itself.

I don't understand that.

Note that dimming halogen lights results in them becoming even more
inefficient in terms of lumens per watt. If you need to dim it, why not
just install smaller lamps?

I understand what you are saying but its case of using what we already
have. Also the light will only be used on an occassionally basis so
hopefully it wont have too damaging effect on our electricity bills!

The lighting circuit currently has a max load of 400W (1.6A)

Is that actual load or calculated load? You must allow a minimum of 100W
per point, so if you have 10 x 40W bulbs that must be considered to be
10 x 100W i.e. 1000W and the circuit is practically fully loaded.

Its the actual load, so what you are saying that you should allow 100W
for each lighting point in doing any calculation irrespective of what
the actual load is?

If this is OK is there any problem with the light not having the
protection of its own separate 5A fuse as I would cut off the plug and
wire is directly into the circuit.

Shouldn't be from that point of view. How will you be connecting the
light to the permanent wiring?

There is an old lighting point that was used for lighting an alcove.
The actual connection will be via a ceiling rose which I can hide
behind some pannelling.

Thank again for your reply.

geoffr wrote:

I would like to connect a halogen up lighter with a dimmer control to a
lighting circuit. However, the up lighter has a 500W bulb (yes I know
this is expensive to run!) and I am concerned about the load on the
lighting circuit.

The rating info on the dimmer switch has two sets of figures with one
set, I assume, referring to the min and max wattage of the bulb stated
as 60-500W. The other set refers to 60-300W which I assume refers to
the rating of the dimmer control itself.

If this is right this would explain why the light came with a 5A fused
plug, because if the load of the whole light fitting was based just on
the bulb rating then the max load would be 2.1A (500/240) and surely a
3A fuse would have been sufficient.

However, if the dimmer switch is rated at 300W then the max load of the
light would increase to 800W (3.3A).

The lighting circuit currently has a max load of 400W (1.6A) and
therefore installing the light still leave a total max load of under
5A. As this is protected by a 6A circuit breaker would this be OK.

If this is OK is there any problem with the light not having the
protection of its own separate 5A fuse as I would cut off the plug and
wire is directly into the circuit.

The switch for the light would be a standard wall switch and am I
also correct in thinking that these switches are rated at 5A.

Any comment gratefully received.


500w of halogen will be way too bright for any normal residence.
Probably about right if you live in a castle.

Dimming it will reduce light output but not reduce power consumptoin
much, and is simply not a smart move. Power consumptoin will be truly
excessive.

Halogen uplighters are a fire risk, the bulbs run way hotter than any
other type of domestic lightbulb, and theyre pointing upwards... not a
good idea.


In short I'd drop the idea and think again. What size room are you
trying to light? What ceiling height, single or double storey height?
Why a freestanding uplighter, and why halogen?


NT

On 31 Aug 2006 08:57:39 -0700, wrote:

500w of halogen will be way too bright for any normal residence.

I have 300W of halogen lighting in my tiny bathroom alone. Plus 60W or
so of normal incandescent.

--
Frank Erskine
Sunderland

On Thu, 31 Aug 2006 19:22:11 +0100 someone who may be Frank Erskine
wrote this:-

500w of halogen will be way too bright for any normal residence.

I have 300W of halogen lighting in my tiny bathroom alone. Plus 60W or
so of normal incandescent.

That might well us a number of things. However, it does not tell us
how sensible such a scheme is compared to a bathroom with a 21W
energy saving bulb.


--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

Frank Erskine wrote:

On 31 Aug 2006 08:57:39 -0700, wrote:

500w of halogen will be way too bright for any normal residence.

I have 300W of halogen lighting in my tiny bathroom alone. Plus 60W or
so of normal incandescent.

That's not lighting. That's heating.
Edgar

In article . com,
"geoffr" writes:
I would like to connect a halogen up lighter with a dimmer control to a
lighting circuit. However, the up lighter has a 500W bulb (yes I know
this is expensive to run!) and I am concerned about the load on the
lighting circuit.

500W halogen is probably a K9 lamp. These are available in
300W and (harder to find) 200W. They are also available in
energy saving versions at 375W and 225W, with same light
output as 500W and 300W respectively (internal infra-red
reflective coating reflects the infra-red back onto the
filament). So pick one of the lower powered versions so
you don't need to use a dimmer.

The rating info on the dimmer switch has two sets of figures with one
set, I assume, referring to the min and max wattage of the bulb stated
as 60-500W. The other set refers to 60-300W which I assume refers to
the rating of the dimmer control itself.

This is wrong, but I don't know what the second set is for.
It might the the max rating of halogen lamp.

If this is right this would explain why the light came with a 5A fused
plug, because if the load of the whole light fitting was based just on
the bulb rating then the max load would be 2.1A (500/240) and surely a
3A fuse would have been sufficient.

Filament lamps have a significant switch-on surge. For these
high power halogen lamps, the initial current is 17 times the
running current, e.g. 35A for your 500W halogen. A 5A fuse
will generally withstand this for long enough for the halogen
lamp to warm up, but a lower current fuse may not.

However, if the dimmer switch is rated at 300W then the max load of the
light would increase to 800W (3.3A).

This makes no sense.

The lighting circuit currently has a max load of 400W (1.6A) and
therefore installing the light still leave a total max load of under
5A. As this is protected by a 6A circuit breaker would this be OK.

Others already explained how you need to work out the loading.

If this is OK is there any problem with the light not having the
protection of its own separate 5A fuse as I would cut off the plug and
wire is directly into the circuit.

If it's a portable lamp, it really needs a plug and socket.
You could fit a 5A BS546 round pin socket to the lighting circuit.
The loss of fuse doesn't matter in this case.

The switch for the light would be a standard wall switch and am I
also correct in thinking that these switches are rated at 5A.

Yes, if not more, but it will be written on the back.

--
Andrew Gabriel

On 2006-08-31 19:54:46 +0100, David Hansen
said:

On Thu, 31 Aug 2006 19:22:11 +0100 someone who may be Frank Erskine
wrote this:-

500w of halogen will be way too bright for any normal residence.

I have 300W of halogen lighting in my tiny bathroom alone. Plus 60W or
so of normal incandescent.

That might well us a number of things. However, it does not tell us
how sensible such a scheme is compared to a bathroom with a 21W
energy saving bulb.

Very sensible.

He has it because he likes it. It's called choice.

wrote:
geoffr wrote:

I would like to connect a halogen up lighter with a dimmer control to a
lighting circuit. However, the up lighter has a 500W bulb (yes I know
this is expensive to run!) and I am concerned about the load on the
lighting circuit.

The rating info on the dimmer switch has two sets of figures with one
set, I assume, referring to the min and max wattage of the bulb stated
as 60-500W. The other set refers to 60-300W which I assume refers to
the rating of the dimmer control itself.

If this is right this would explain why the light came with a 5A fused
plug, because if the load of the whole light fitting was based just on
the bulb rating then the max load would be 2.1A (500/240) and surely a
3A fuse would have been sufficient.

However, if the dimmer switch is rated at 300W then the max load of the
light would increase to 800W (3.3A).

The lighting circuit currently has a max load of 400W (1.6A) and
therefore installing the light still leave a total max load of under
5A. As this is protected by a 6A circuit breaker would this be OK.

If this is OK is there any problem with the light not having the
protection of its own separate 5A fuse as I would cut off the plug and
wire is directly into the circuit.

The switch for the light would be a standard wall switch and am I
also correct in thinking that these switches are rated at 5A.

Any comment gratefully received.


500w of halogen will be way too bright for any normal residence.
Probably about right if you live in a castle.

Dimming it will reduce light output but not reduce power consumptoin
much, and is simply not a smart move. Power consumptoin will be truly
excessive.

Halogen uplighters are a fire risk, the bulbs run way hotter than any
other type of domestic lightbulb, and theyre pointing upwards... not a
good idea.


In short I'd drop the idea and think again. What size room are you
trying to light? What ceiling height, single or double storey height?
Why a freestanding uplighter, and why halogen?

The house is Victorian and the ceilings are 12' high so there is in
excess of 6' clearance. I have used it in rooms with lower ceilings and
it seemed OK or at least it didn't leave black scorch marks!

Its being used as its simply what I have available, although even if I
was starting from scratch I would choose this type of light as it
appears that the only downside is the electricity consumption. The
quality of halogen light seems to me to be superior to any other as it
does give a very good quality of light in high-ceilinged rooms. Having
said that I am not too keen on the 50W halogen spot lights as they give
too narrow a beam.

Andrew Gabriel wrote:

500W halogen is probably a K9 lamp. These are available in
300W and (harder to find) 200W. They are also available in
energy saving versions at 375W and 225W, with same light
output as 500W and 300W respectively (internal infra-red
reflective coating reflects the infra-red back onto the
filament). So pick one of the lower powered versions so
you don't need to use a dimmer.

I'm interested in these energy saving versions. I assume they are
available from B&Q etc?

Thanks for all the comments.

In article . com,
"geoffr" writes:
Andrew Gabriel wrote:

500W halogen is probably a K9 lamp. These are available in
300W and (harder to find) 200W. They are also available in
energy saving versions at 375W and 225W, with same light
output as 500W and 300W respectively (internal infra-red
reflective coating reflects the infra-red back onto the
filament). So pick one of the lower powered versions so
you don't need to use a dimmer.

I'm interested in these energy saving versions. I assume they are
available from B&Q etc?

They are not easy to find. B&Q do have them in stock
occasionally, but I don't recall seeing them in other
retail outlets. They were a General Electric invention,
but you may find other manufacturers making them too
now.

--
Andrew Gabriel

Frank Erskine wrote:
On 31 Aug 2006 08:57:39 -0700, wrote:

500w of halogen will be way too bright for any normal residence.

I have 300W of halogen lighting in my tiny bathroom alone. Plus 60W or
so of normal incandescent.

I do occasionally see lighting like this, and find it a truly
unpleasant experience.


NT

geoffr wrote:

I would like to connect a halogen up lighter with a dimmer control to a
lighting circuit. However, the up lighter has a 500W bulb (yes I know

Its being used as its simply what I have available,

It doesnt much matter what you have available, as the electricity
consumption will be many times the purchase cost of any reasonable
fitting.

If youre determined to use halogen, at least omit the dimmer and get
the right power bulb for the job.


NT

Owain wrote:

If it's a screw connection it must remain accessible, and I'm not sure
that ceiling roses are permitted other than ceilings, because they can
give access to live parts without use of a tool. Also check that the
"old" lighting point is earthed.

Which if you are 6' or over, and live in a modern house, means all roses
give access to live parts without a tool regardless of where they are! ;-)

--
Cheers,

John.

/================================================== ===============\
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|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

Edgar Iredale wrote:

I have 300W of halogen lighting in my tiny bathroom alone. Plus 60W or
so of normal incandescent.


That's not lighting. That's heating.

Which in a bathroom is perhaps quite a good idea!

--
Cheers,

John.

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

Andrew Gabriel wrote:

The rating info on the dimmer switch has two sets of figures with one
set, I assume, referring to the min and max wattage of the bulb stated
as 60-500W. The other set refers to 60-300W which I assume refers to
the rating of the dimmer control itself.


This is wrong, but I don't know what the second set is for.
It might the the max rating of halogen lamp.

The second set may be the derated capacity when used with an inductive
load (i.e. a halogen!)



--
Cheers,

John.

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

John Rumm wrote:
Andrew Gabriel wrote:

The rating info on the dimmer switch has two sets of figures with one
set, I assume, referring to the min and max wattage of the bulb stated
as 60-500W. The other set refers to 60-300W which I assume refers to
the rating of the dimmer control itself.


This is wrong, but I don't know what the second set is for.
It might the the max rating of halogen lamp.

The second set may be the derated capacity when used with an inductive
load (i.e. a halogen!)

Since when has a halogen lamp been an inductive load? Even if you
mean a transormer driven low voltage halogen it won't be very
inductive - nothing like a motor or solenoid.

--
Chris Green

John Rumm wrote:
Andrew Gabriel wrote:

The rating info on the dimmer switch has two sets of figures with one
set, I assume, referring to the min and max wattage of the bulb stated
as 60-500W. The other set refers to 60-300W which I assume refers to
the rating of the dimmer control itself.


This is wrong, but I don't know what the second set is for.
It might the the max rating of halogen lamp.

The second set may be the derated capacity when used with an inductive
load (i.e. a halogen!)



--
Cheers,

John.

If its any help the first set of information is stated as follows:

(S) (D) Only
(N) (FI) 60-300W
50-60HZ

The 2nd set of figures definitely refers to the bulb rating as there is
a light bulb sign next to the figures of 60-500W. I didnt see this on
initial inspection is not easy to read as its raised black lettering on
a black background.

The light was advertised as 500W and and came with this wattage bulb.

In article ,
John Rumm writes:
Owain wrote:

If it's a screw connection it must remain accessible, and I'm not sure
that ceiling roses are permitted other than ceilings, because they can
give access to live parts without use of a tool. Also check that the
"old" lighting point is earthed.

Which if you are 6' or over, and live in a modern house, means all roses
give access to live parts without a tool regardless of where they are! ;-)

So do (nearly) all BC and ES lampholders.

--
Andrew Gabriel

In article . com,
geoffr writes

The rating info on the dimmer switch has two sets of figures with one
set, I assume, referring to the min and max wattage of the bulb stated
as 60-500W. The other set refers to 60-300W which I assume refers to
the rating of the dimmer control itself.

Could be because those halogen bulbs commonly come in 500W and 300W
variants. You just fit whatever bulb suits you.

--
(\__/)
(='.'=) This is Bunny. Copy and paste Bunny into your
(")_(") signature to help him gain world domination.
http://www.thisisbunny.com/