Low voltage halogen lights problem
 

Hi
I seem to have continual problems with some of my LV halogens. I have
them all over the flat but a set of eight seeming to be continually
blowing. I have replaced the transformers and the lights but five have
just blown again, and its usually the transformer that goes. The ceiling
void should be large enough as its about a foot. I dont have any
problems with any lights on the same circuit just these ones. Is it
possible that there is an earth leak, and if so how would I test? The
ceiling is plaster board without any access panels so I can only gain
access through the light fittings.

Any help or suggestions would be appreciated

Adrian

In an earlier contribution to this discussion,
Adrian wrote:

Hi
I seem to have continual problems with some of my LV halogens. I have
them all over the flat but a set of eight seeming to be continually
blowing. I have replaced the transformers and the lights but five have
just blown again, and its usually the transformer that goes. The
ceiling void should be large enough as its about a foot. I dont
have any problems with any lights on the same circuit just these
ones. Is it possible that there is an earth leak, and if so how would
I test? The ceiling is plaster board without any access panels so I
can only gain access through the light fittings.

Any help or suggestions would be appreciated

Adrian

What wattage are the lamps? What wattage are the transformers? What type of
transformer are they - electronic or wire wound? How many lamps per
transformer? What gauge of cable connects the lamps to the transformers? Are
any of the lamps very close to joists or other structural members?

It sounds as if the transformer is overloaded. Your answers to the questions
above may help to determine whether that is the case. If you have a large
number of low wattage lamps connected to a single electronic transformer,
you need to down-rate the transformer by quite a lot. Maybe this hasn't been
done? [e.g. a 210 watt transformer is fine for 4 x 50 watt lamps - but not
for 10 x 20 watt lamps]
--
Cheers,
Set Square
______
Please reply to newsgroup. Reply address is invalid.

Set Square wrote:
In an earlier contribution to this discussion,
Adrian wrote:


Hi
I seem to have continual problems with some of my LV halogens. I have
them all over the flat but a set of eight seeming to be continually
blowing. I have replaced the transformers and the lights but five have
just blown again, and its usually the transformer that goes. The
ceiling void should be large enough as its about a foot. I dont
have any problems with any lights on the same circuit just these
ones. Is it possible that there is an earth leak, and if so how would
I test? The ceiling is plaster board without any access panels so I
can only gain access through the light fittings.

Any help or suggestions would be appreciated

Adrian


What wattage are the lamps? What wattage are the transformers? What type of
transformer are they - electronic or wire wound? How many lamps per
transformer? What gauge of cable connects the lamps to the transformers? Are
any of the lamps very close to joists or other structural members?

It sounds as if the transformer is overloaded. Your answers to the questions
above may help to determine whether that is the case. If you have a large
number of low wattage lamps connected to a single electronic transformer,
you need to down-rate the transformer by quite a lot. Maybe this hasn't been
done? [e.g. a 210 watt transformer is fine for 4 x 50 watt lamps - but not
for 10 x 20 watt lamps]

Each halogen bulb is 50watts. Each bulb has its own electronic
transformer which is fully dimmable, min load 20w max load 60w.
None of the lamps if close to a structural beam.
I'm not sure of the guage, standard lighting flex, easily capable of
carrying a decent ampage.

In an earlier contribution to this discussion,
Adrian wrote:


Each halogen bulb is 50watts. Each bulb has its own electronic
transformer which is fully dimmable, min load 20w max load 60w.
None of the lamps if close to a structural beam.
I'm not sure of the guage, standard lighting flex, easily capable of
carrying a decent ampage.

Are you using identical lamp/transformer combinations in other rooms without
this level of failure? If so, you need to try to work out what is different
about this particular room and its ceiling space. It's unlikely to be an
earth problem - the LV side is invariably not earthed.
--
Cheers,
Set Square
______
Please reply to newsgroup. Reply address is invalid.

Set Square wrote:

It sounds as if the transformer is overloaded.

Excuse my ignorance, but how does it sound that way? How and why would
an overloaded transformer blow bulbs??


--
Grunff

Adrian wrote:

I seem to have continual problems with some of my LV halogens. I have
them all over the flat but a set of eight seeming to be continually
blowing. I have replaced the transformers and the lights but five have
just blown again, and its usually the transformer that goes. The ceiling
void should be large enough as its about a foot. I dont have any
problems with any lights on the same circuit just these ones. Is it
possible that there is an earth leak, and if so how would I test? The
ceiling is plaster board without any access panels so I can only gain
access through the light fittings.

Any help or suggestions would be appreciated


I don't see how an 'earth leak' could possibly be the cause. It sounds
very much like that set of bulbs is overheating. Is the void above them
insulated?


--
Grunff

In an earlier contribution to this discussion,
Grunff wrote:

Set Square wrote:

It sounds as if the transformer is overloaded.

Excuse my ignorance, but how does it sound that way?

Because the OP wrote, and I quote "its usually the transformer that goes"!

How and why would
an overloaded transformer blow bulbs??

It wouldn't - but it's not (usually) the bulbs which are failing.

--
Cheers,
Set Square
______
Please reply to newsgroup. Reply address is invalid.

Adrian wrote:

Each halogen bulb is 50watts. Each bulb has its own electronic
transformer which is fully dimmable, min load 20w max load 60w.

What type of switching do you have? (i.e. conventional switch or
dimmer). Is this different from the other rooms?



--
Cheers,

John.

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

Set Square wrote:

Because the OP wrote, and I quote "its usually the transformer that goes"!

Hmm. You make a good argument. D'oh!!



It wouldn't - but it's not (usually) the bulbs which are failing.

slap forehead again


--
Grunff

John Rumm wrote:
Adrian wrote:

Each halogen bulb is 50watts. Each bulb has its own electronic
transformer which is fully dimmable, min load 20w max load 60w.


What type of switching do you have? (i.e. conventional switch or
dimmer). Is this different from the other rooms?



Conventional switch. In the same room there is another set of lights on
dimmers.

Grunff wrote:
Adrian wrote:

I seem to have continual problems with some of my LV halogens. I have
them all over the flat but a set of eight seeming to be continually
blowing. I have replaced the transformers and the lights but five have
just blown again, and its usually the transformer that goes. The
ceiling void should be large enough as its about a foot. I dont have
any problems with any lights on the same circuit just these ones. Is
it possible that there is an earth leak, and if so how would I test?
The ceiling is plaster board without any access panels so I can only
gain access through the light fittings.

Any help or suggestions would be appreciated



I don't see how an 'earth leak' could possibly be the cause. It sounds
very much like that set of bulbs is overheating. Is the void above them
insulated?


No its a suspended plaster ceiling with a good foot of space. On some of
the lights it is definitely the transformer that has gone, on others the
bulbs. It could be overheating but in every other room there is the same
setup and they all seem to be OK.?

Grunff wrote in message ...
Adrian wrote:

I seem to have continual problems with some of my LV halogens. I have
them all over the flat but a set of eight seeming to be continually
blowing. I have replaced the transformers and the lights but five have
just blown again, and its usually the transformer that goes. The ceiling
void should be large enough as its about a foot. I dont have any
problems with any lights on the same circuit just these ones. Is it
possible that there is an earth leak, and if so how would I test? The
ceiling is plaster board without any access panels so I can only gain
access through the light fittings.

Any help or suggestions would be appreciated

Hi
I also have a problem of blowing transformers and/or bulbs. I have
got as far as seeing that certain brands of electronic transformers
can only operate upto a configuration of four when connected to a
dimmer. I have yet to install the range of transformers and dimmer
that I reckon will do the job so can't give a reccomendation yet.
You might want to check with the manufacturer of your transformers
that they are suitable for the number of lights you have installed and
wattage ( or VA as it seems to be known ) and make sure that the
dimmer is the correct type for your transformers. HTH.

Adrian wrote:

John Rumm wrote:

What type of switching do you have? (i.e. conventional switch or
dimmer). Is this different from the other rooms?



Conventional switch. In the same room there is another set of lights on
dimmers.

Had a feeling you were going to say that ;-)

I think you may find the answer in this thread... be warned it does
degenerate when small man guarding the bridge makes an appearance! ;-)

http://groups.google.com/groups?hl=e...gle%2BSe arch
or
http://tinyurl.com/5m977

--
Cheers,

John.

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