I've googled for this but found nothing that really relates to the
problem, though it's hard to form a search which doesn't produce
references to 50Hz flickering or to use of dimmers, neither of which is
my problem. So if this is an FAQ please point me to it ...

I had my bathroom/adjacent toilet completely "done" last August. The
bathroom has five LV 50w halogen down-lighters in it, the toilet another
three. The house wiring was done about a year before.

All was well for quite a while then one of the lights in the bathroom
started to act up. It started by fading and brightening for a fraction
of a second, then for seconds at a time, and over a period of two or
three weeks (while we had calls in to the team that did the fitting) it
went to being out for minutes at a time and then finally dead. It's not
the bulb because it works OK in another fitting.

Then about a week ago another one of the five in the bathroom started
with the same performance; it's got somewhat worse by now, and today one
of the ones in the separate toilet joined in. (And we're starting to
write breach-of-contract letters ...)

Can someone suggest what's causing this? I have a reasonable knowledge
of electronics and what not, and can't imagine what's going on. When
they finally do pitch up, how much of it are they going to have to have
access to? I've insulated the loft since the job was done.

--

Henry Law Manchester, England

"Henry Law" wrote in message
...

I had my bathroom/adjacent toilet completely "done" last August. The
bathroom has five LV 50w halogen down-lighters in it, the toilet another
three. The house wiring was done about a year before.

All was well for quite a while then one of the lights in the bathroom
started to act up. It started by fading and brightening for a fraction of
a second, then for seconds at a time,

Can someone suggest what's causing this? I have a reasonable knowledge of
electronics and what not, and can't imagine what's going on. When they
finally do pitch up, how much of it are they going to have to have access
to? I've insulated the loft since the job was done.

I've seen this recently.

I have some 12v halogens in my bathroom.
They were powered by a traditional iron-cored transformer.
They worked perfectly.

One day, no light.
Transformer had died.

Replacement 'transformer' is not actually a transformer, but is a
Switch-mode power supply.

It behaves exactly as you describe.
Intetermittent 'flickering', for fractions of a second, lasting for up to a
couple of minutes.
Seems worse when caught out of the corner of the eye.

I suspect that the SMPS is just a bit ****.
It is correctly rated for the load ( not over- or under- loaded. ).

I suspect replacing the 'transformer' with a real transformer will cure it.

--
Ron

Ron Lowe wrote:

All was well for quite a while then one of the lights in the bathroom
started to act up. It started by fading and brightening for a
fraction of a second, then for seconds at a time,

I've seen this recently.

I have some 12v halogens in my bathroom.
They were powered by a traditional iron-cored transformer.
They worked perfectly.

One day, no light.
Transformer had died.

Replacement 'transformer' is not actually a transformer, but is a
Switch-mode power supply.

Interesting. I shall go and peer intently at it. Actually I shall
start by trying to find "it" because all I've seen so far (while
insulating the loft) is little oblong boxes, about 75mmx50x50, one
adjacent to each individual light fitting. I haven't seen a single
transformer/SMPS so far. Where's me torch ...?

--

Henry Law Manchester, England

Henry Law wrote:
Ron Lowe wrote:

All was well for quite a while then one of the lights in the
bathroom started to act up. It started by fading and brightening
for a fraction of a second, then for seconds at a time,

I've seen this recently.

I have some 12v halogens in my bathroom.
They were powered by a traditional iron-cored transformer.
They worked perfectly.

One day, no light.
Transformer had died.

Replacement 'transformer' is not actually a transformer, but is a
Switch-mode power supply.

Interesting. I shall go and peer intently at it. Actually I shall
start by trying to find "it" because all I've seen so far (while
insulating the loft) is little oblong boxes, about 75mmx50x50, one
adjacent to each individual light fitting. I haven't seen a single
transformer/SMPS so far. Where's me torch ...?

Those little oblong boxes *are* the transformers/SMPSs - or at least they
are here.

John wrote:
Henry Law wrote:
start by trying to find "it" because all I've seen so far (while
insulating the loft) is little oblong boxes, about 75mmx50x50, one
adjacent to each individual light fitting. I haven't seen a single
transformer/SMPS so far. Where's me torch ...?

Those little oblong boxes *are* the transformers/SMPSs - or at least they
are here.

Yes that's what I thought; but the likelihood of _three_ of them (out of
eight) going on the blink within a few weeks of one another has surely
got to be very low. Er, hasn't it?

--

Henry Law Manchester, England

On 28 Jan, 20:45, Henry Law wrote:
John wrote:
Henry Law wrote:
start by trying to find "it" because all I've seen so far (while
insulating the loft) is little oblong boxes, about 75mmx50x50, one
adjacent to each individual light fitting. *I haven't seen a single
transformer/SMPS so far. *Where's me torch ...?

Those little oblong boxes *are* the transformers/SMPSs - or at least they
are here.

Yes that's what I thought; but the likelihood of _three_ of them (out of
eight) going on the blink within a few weeks of one another has surely
got to be very low. *Er, hasn't it?

--

Henry Law * * * * * *Manchester, England

Not if you get a bad batch, or they get hammered with voltage spike or
you`ve been a bit generous with the insulation.....

Mode and IBL make the most reliable LV electronic trafos but cost a
premium to some of the almost as good far eastern and European brands.

Adam

Henry Law wrote:
Ron Lowe wrote:

All was well for quite a while then one of the lights in the bathroom
started to act up. It started by fading and brightening for a
fraction of a second, then for seconds at a time,

I've seen this recently.

I have some 12v halogens in my bathroom.
They were powered by a traditional iron-cored transformer.
They worked perfectly.

One day, no light.
Transformer had died.

Replacement 'transformer' is not actually a transformer, but is a
Switch-mode power supply.

Interesting. I shall go and peer intently at it. Actually I shall
start by trying to find "it" because all I've seen so far (while
insulating the loft) is little oblong boxes, about 75mmx50x50, one
adjacent to each individual light fitting. I haven't seen a single
transformer/SMPS so far. Where's me torch ...?

I'll go along with a **** power supply too.

Henry Law wrote:
I've googled for this but found nothing that really relates to the
problem, though it's hard to form a search which doesn't produce
references to 50Hz flickering or to use of dimmers, neither of which is
my problem. So if this is an FAQ please point me to it ...

I had my bathroom/adjacent toilet completely "done" last August. The
bathroom has five LV 50w halogen down-lighters in it, the toilet another
three. The house wiring was done about a year before.

All was well for quite a while then one of the lights in the bathroom
started to act up. It started by fading and brightening for a fraction
of a second, then for seconds at a time, and over a period of two or
three weeks (while we had calls in to the team that did the fitting) it
went to being out for minutes at a time and then finally dead. It's not
the bulb because it works OK in another fitting.

Then about a week ago another one of the five in the bathroom started
with the same performance; it's got somewhat worse by now, and today one
of the ones in the separate toilet joined in. (And we're starting to
write breach-of-contract letters ...)

Can someone suggest what's causing this? I have a reasonable knowledge
of electronics and what not, and can't imagine what's going on. When
they finally do pitch up, how much of it are they going to have to have
access to? I've insulated the loft since the job was done.

Its a bad connection somewhere, either on the bulb holder, he wire to
it, or within the smpsu/transformer itself. Hook a multimeter onto the
psu output and see if it varies as the lights vary or not. Hard to
believe you have electronics knowledge.


NT

On 29 Jan, 00:44, wrote:
Henry Law wrote:
I've googled for this but found nothing that really relates to the
problem, though it's hard to form a search which doesn't produce
references to 50Hz flickering or to use of dimmers, neither of which is
my problem. So if this is an FAQ please point me to it ...

I had my bathroom/adjacent toilet completely "done" last August. *The
bathroom has five LV 50w halogen down-lighters in it, the toilet another
three. *The house wiring was done about a year before.

All was well for quite a while then one of the lights in the bathroom
started to act up. *It started by fading and brightening for a fraction
of a second, then for seconds at a time, and over a period of two or
three weeks (while we had calls in to the team that did the fitting) it
went to being out for minutes at a time and then finally dead. *It's not
the bulb because it works OK in another fitting.

Then about a week ago another one of the five in the bathroom started
with the same performance; it's got somewhat worse by now, and today one
of the ones in the separate toilet joined in. *(And we're starting to
write breach-of-contract letters ...)

Can someone suggest what's causing this? *I have a reasonable knowledge
of electronics and what not, and can't imagine what's going on. *When
they finally do pitch up, how much of it are they going to have to have
access to? *I've insulated the loft since the job was done.

Its a bad connection somewhere, either on the bulb holder, he wire to
it, or within the smpsu/transformer itself. Hook a multimeter onto the
psu output and see if it varies as the lights vary or not. Hard to
believe you have electronics knowledge.

NT

High frequebcy output on most LV electronic trafos can give strange
readings even when working properly, lamp load should smooth it out a
bit but substitution is really prefered fault finding method...

Good point about checking lamp holders.

Adam

"Henry Law" wrote in message
...
I've googled for this but found nothing that really relates to the
problem, though it's hard to form a search which doesn't produce
references to 50Hz flickering or to use of dimmers, neither of which is my
problem. So if this is an FAQ please point me to it ...

I had my bathroom/adjacent toilet completely "done" last August. The
bathroom has five LV 50w halogen down-lighters in it, the toilet another
three. The house wiring was done about a year before.

All was well for quite a while then one of the lights in the bathroom
started to act up. It started by fading and brightening for a fraction of
a second, then for seconds at a time, and over a period of two or three
weeks (while we had calls in to the team that did the fitting) it went to
being out for minutes at a time and then finally dead. It's not the bulb
because it works OK in another fitting.

Then about a week ago another one of the five in the bathroom started with
the same performance; it's got somewhat worse by now, and today one of the
ones in the separate toilet joined in. (And we're starting to write
breach-of-contract letters ...)

Can someone suggest what's causing this? I have a reasonable knowledge of
electronics and what not, and can't imagine what's going on. When they
finally do pitch up, how much of it are they going to have to have access
to? I've insulated the loft since the job was done.

Can be due to excessively long 12V lead from "electronic transformer". My
mate had this issue in his new kitchen extension. First he changed the LV
leads to about 12 inch long from 8 foot odd and light flickering/brightness
issues went away. (I think it actually states this in the fitting
instructions, LV lead no longer than 12"). Very unhandily the builder bolted
all the transformers to a beam in the ceiling meaning holes had to be cut in
ceiling to access them.

Then the next issue was the 50W "electronic transformers" cutting out after
many hours usually on very hot summer evenings or winter Saturday & Sunday
evenings when the heating had been on all day. So he changed all the
electronic transformers to 100W (and/or 70W) ones and lights work 100% time
no problem. I think the 100W/70W replacements came from TLC.

Adam Aglionby wrote:
On 29 Jan, 00:44, wrote:
Henry Law wrote:
snipped

I had my bathroom/adjacent toilet completely "done" last August. *The
bathroom has five LV 50w halogen down-lighters in it, the toilet another
three. *The house wiring was done about a year before.

All was well for quite a while then one of the lights in the bathroom
started to act up. *It started by fading and brightening for a fraction
of a second, then for seconds at a time, and over a period of two or
three weeks (while we had calls in to the team that did the fitting) it
went to being out for minutes at a time and then finally dead. *It's not
the bulb because it works OK in another fitting.

Its a bad connection somewhere, either on the bulb holder, he wire to
it, or within the smpsu/transformer itself. Hook a multimeter onto the
psu output and see if it varies as the lights vary or not. Hard to
believe you have electronics knowledge.

High frequebcy output on most LV electronic trafos can give strange
readings even when working properly

makes no difference, what youre looking or is variation, not absolute
value.


NT

wrote in message
...
Adam Aglionby wrote:
On 29 Jan, 00:44, wrote:
Henry Law wrote:
snipped

I had my bathroom/adjacent toilet completely "done" last August. The
bathroom has five LV 50w halogen down-lighters in it, the toilet
another
three. The house wiring was done about a year before.

All was well for quite a while then one of the lights in the bathroom
started to act up. It started by fading and brightening for a fraction
of a second, then for seconds at a time, and over a period of two or
three weeks (while we had calls in to the team that did the fitting)
it
went to being out for minutes at a time and then finally dead. It's
not
the bulb because it works OK in another fitting.

Its a bad connection somewhere, either on the bulb holder, he wire to
it, or within the smpsu/transformer itself. Hook a multimeter onto the
psu output and see if it varies as the lights vary or not. Hard to
believe you have electronics knowledge.

High frequebcy output on most LV electronic trafos can give strange
readings even when working properly

makes no difference, what youre looking or is variation, not absolute
value.


NT

Don't they have thermal cutouts? and you insulated the loft after
installation?
Usual cause is power supply playing up but I've seen quite few that were
cured by simply letting the heat escape.

My threepennorth anyway ...

Jb