Halogen lights half off
 

Last night my electrics tripped (lights). On resetting the fuse only 3
of the 12V 20W lights came back on. Bulbs seem OK. Can the transformer
half fuse? why have only half gone off?do transformers divive into
halves-and do they break?. Problem is they are the type that are set
into the ceiling and it will be a pain to get at the transformer!. any
help or advice appreciated

wrote in message
oups.com...
Last night my electrics tripped (lights). On resetting the fuse only
3
of the 12V 20W lights came back on. Bulbs seem OK. Can the
transformer
half fuse? why have only half gone off?do transformers divive into
halves-and do they break?. Problem is they are the type that are set
into the ceiling and it will be a pain to get at the transformer!.
any
help or advice appreciated


I would imagine the lights are split between two transformers, one of
which in a fit of spite in it's death throws tripped your fuse.

AWEM

On 23 Sep 2005 01:41:25 -0700, "
wrote:

Last night my electrics tripped (lights). On resetting the fuse only 3
of the 12V 20W lights came back on. Bulbs seem OK. Can the transformer
half fuse? why have only half gone off?do transformers divive into
halves-and do they break?. Problem is they are the type that are set
into the ceiling and it will be a pain to get at the transformer!. any
help or advice appreciated

Are you sure you don't have more than one transformer ? They're not rated
all that highly due to limitations on the current load. Three of your bulbs
pull 5A, the same as most entire mains-fed circuits.

--
Star Trek II, the musical version: The Rap Of Kahn.

On 23 Sep 2005 01:41:25 -0700, "
wrote:

Last night my electrics tripped (lights). On resetting the fuse only 3
of the 12V 20W lights came back on. Bulbs seem OK. Can the transformer
half fuse? why have only half gone off?do transformers divive into
halves-and do they break?. Problem is they are the type that are set
into the ceiling and it will be a pain to get at the transformer!. any
help or advice appreciated

Quite often the cheap ones are 3 lamps per transformer. Measure the
voltage across the lamp terminals. If it is 0v you have two choices to
access the transformer: from above or below.

Is there a loft above the lights or are their floorboards in a room
above? Floorboards aren't too difficult to get up unless they are
tongue and groove, in which case you'd almost be better cutting a hole
in the ceiling.

Suitable transformers are available from toolstation.com part numbers:
55497, 67666, 28118

Mr F.

On Fri, 23 Sep 2005 10:01:41 +0100, John Laird
scrawled:

Are you sure you don't have more than one transformer ?

Sounds likely to me.

They're not rated
all that highly due to limitations on the current load. Three of your bulbs
pull 5A, the same as most entire mains-fed circuits.

Well, they may not be as common as the 3 lamps per transformer sets or
the individual transformer per light arrangement but you can quite
easily get 500VA transformers and drive 10 lights off one. Only the
not highly rated ones are not highly rated. ;)
--
Stuart @ SJW Electrical

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On Fri, 23 Sep 2005 11:15:03 +0100, Lurch
wrote:

On Fri, 23 Sep 2005 10:01:41 +0100, John Laird
scrawled:

Are you sure you don't have more than one transformer ?

Sounds likely to me.

They're not rated
all that highly due to limitations on the current load. Three of your bulbs
pull 5A, the same as most entire mains-fed circuits.

Well, they may not be as common as the 3 lamps per transformer sets or
the individual transformer per light arrangement but you can quite
easily get 500VA transformers and drive 10 lights off one. Only the
not highly rated ones are not highly rated. ;)

No doubt. But what sort of cable can you get that can carry up to 40A ?

--
The Three Food Groups: Frozen, Instant, and Take Out.

On Fri, 23 Sep 2005 18:10:43 +0100, John Laird wrote:

On Fri, 23 Sep 2005 11:15:03 +0100, Lurch
wrote:
...but you can quite
easily get 500VA transformers and drive 10 lights off one.

No doubt. But what sort of cable can you get that can carry up to 40A ?

Can't believe I asked that ! You just connect up several in parallel, of
course.

Doh.

--
Guns don't kill people...Class 2 Phasers do!

On Fri, 23 Sep 2005 18:10:43 +0100, John Laird
scrawled:

But what sort of cable can you get that can carry up to 40A ?

Depends how far you want to carry it. ;)
--
Stuart @ SJW Electrical

Please Reply to group

"John Laird" wrote in message
...
On Fri, 23 Sep 2005 18:10:43 +0100, John Laird wrote:

On Fri, 23 Sep 2005 11:15:03 +0100, Lurch
wrote:
...but you can quite
easily get 500VA transformers and drive 10 lights off one.

No doubt. But what sort of cable can you get that can carry up to 40A ?

Can't believe I asked that ! You just connect up several in parallel, of
course.

With the correct fuse in each circuit.

John Laird wrote:

On Fri, 23 Sep 2005 18:10:43 +0100, John Laird wrote:


On Fri, 23 Sep 2005 11:15:03 +0100, Lurch
wrote:

...but you can quite
easily get 500VA transformers and drive 10 lights off one.

No doubt. But what sort of cable can you get that can carry up to 40A ?


Can't believe I asked that ! You just connect up several in parallel, of
course.

Or buy some...

Car speaker cable would probably do 100A easily.

Car jump leads will do about 400A.

Doh.

The Natural Philosopher wrote:

John Laird wrote:

On Fri, 23 Sep 2005 18:10:43 +0100, John Laird wrote:

On Fri, 23 Sep 2005 11:15:03 +0100, Lurch
wrote:

...but you can quite
easily get 500VA transformers and drive 10 lights off one.

No doubt. But what sort of cable can you get that can carry up to 40A ?

Can't believe I asked that ! You just connect up several in parallel, of
course.

Or buy some...

Car speaker cable would probably do 100A easily.

Car jump leads will do about 400A.

The croc clips might short together when you clip them onto the
light fittings, but you can always cut them off and taper the
conductor strands down to something that will fit the
terminals..... NOT!

Chris
--
Chris J Dixon Nottingham UK


Have dancing shoes, will ceilidh.

Chris J Dixon wrote:
The Natural Philosopher wrote:


John Laird wrote:


On Fri, 23 Sep 2005 18:10:43 +0100, John Laird wrote:


On Fri, 23 Sep 2005 11:15:03 +0100, Lurch
wrote:


...but you can quite
easily get 500VA transformers and drive 10 lights off one.

No doubt. But what sort of cable can you get that can carry up to 40A ?

Can't believe I asked that ! You just connect up several in parallel, of
course.


Or buy some...

Car speaker cable would probably do 100A easily.

Car jump leads will do about 400A.


The croc clips might short together when you clip them onto the
light fittings, but you can always cut them off and taper the
conductor strands down to something that will fit the
terminals..... NOT!

Of course you can!

Any transformer that is rated at 40A will come with connecters adequate
for the job.

100A mains feeds to a house are not uncommon.

The wire exists, the connectors exist.
When connecting to LV lamps you start them anyway mostly - so the final
feeds are lower current.

100A is not really THAT much.

Chris

The Natural Philosopher wrote:

Chris J Dixon wrote:

The croc clips might short together when you clip them onto the
light fittings, but you can always cut them off and taper the
conductor strands down to something that will fit the
terminals..... NOT!

Of course you can!

Sorry, I thought you were joking, and was simply joining in the
fun.

I thought tapering the strands was about as acceptable as those
old ceramic Screwit connectors.


Any transformer that is rated at 40A will come with connecters adequate
for the job.

OK, I see that makes sense, but if for lighting, it is possible
that it has been assumed that the wiring will be run to
individual lights in parallel, and thus a number of small
connectors provided.

The wire exists, the connectors exist.
When connecting to LV lamps you start them anyway mostly - so the final
feeds are lower current.

Run that last sentence by me again?

Chris
--
Chris J Dixon Nottingham UK


Have dancing shoes, will ceilidh.

Chris J Dixon wrote:
The Natural Philosopher wrote:


Chris J Dixon wrote:


The croc clips might short together when you clip them onto the
light fittings, but you can always cut them off and taper the
conductor strands down to something that will fit the
terminals..... NOT!


Of course you can!


Sorry, I thought you were joking, and was simply joining in the
fun.

I thought tapering the strands was about as acceptable as those
old ceramic Screwit connectors.


Any transformer that is rated at 40A will come with connecters adequate
for the job.


OK, I see that makes sense, but if for lighting, it is possible
that it has been assumed that the wiring will be run to
individual lights in parallel, and thus a number of small
connectors provided.


The wire exists, the connectors exist.
When connecting to LV lamps you start them anyway mostly - so the final
feeds are lower current.


Run that last sentence by me again?

s/start/star

?

Chris

Sorry to sound stupid here but there are 6 x 20 bulbls , if I buy a new
transformer the ones advertised come as 105W, or 150 W. Wish do I need

On 27 Sep 2005 02:58:52 -0700, "
scrawled:

Sorry to sound stupid here but there are 6 x 20 bulbls , if I buy a new
transformer the ones advertised come as 105W, or 150 W. Wish do I need

The clue is in the question. Have you actually found a transformer and
tested it in situ yet?
--
Stuart @ SJW Electrical

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Sorry Again. Want to buy one of
http://www.toolstation.com/search.html?searchstr=55497. Can't test it
before I buy!

On 27 Sep 2005 05:02:07 -0700, "
scrawled:

Sorry Again. Want to buy one of
http://www.toolstation.com/search.html?searchstr=55497. Can't test it
before I buy!

But that's not the one in your kitchen which is the one that needs
testing.

I suggest you call someone in as basic comprehension is lacking here
and is a bit of a hindrance.
--
Stuart @ SJW Electrical

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