My daughter has some under cupboard lights - about 3inch diameter
reflectors with a G4 bulb.

They fail frequently and I would like your advice on LED replacements.

LED Bulbs?

New fittings that would work of existing transformer????

Replace the lot with LED Tape? (However, this would take 3 separate
lengths)?

DerbyBorn wrote:

My daughter has some under cupboard lights - about 3inch diameter
reflectors with a G4 bulb. They fail frequently and I would like your
advice on LED replacements.

The general impression I get is that G4 are too small to allow LEDs to
cool properly, so they would fail frequently too ...

On 18/03/2017 21:02, DerbyBorn wrote:
My daughter has some under cupboard lights - about 3inch diameter
reflectors with a G4 bulb.

They fail frequently and I would like your advice on LED replacements.

LED Bulbs?

New fittings that would work of existing transformer????

Replace the lot with LED Tape? (However, this would take 3 separate
lengths)?


I have recently second fixed a kitchens electrics and the customer
supplied the lights. They were led 230V (so you can bin the transformer)
and I guess very similar in style to the ones your daughter has.

I am sure that they were called Robus Captain.



--
Adam

In article 6,
DerbyBorn wrote:
My daughter has some under cupboard lights - about 3inch diameter
reflectors with a G4 bulb.

They fail frequently and I would like your advice on LED replacements.

Where are you buying your spares from? I've found shed bought lamps seem
to be of pretty poor quality life wise, so only buy from TLC these days.

LED Bulbs?

New fittings that would work of existing transformer????

Replace the lot with LED Tape? (However, this would take 3 separate
lengths)?

IIRC, G4 is one of those very small lamps that can't be replaced with LED
successfully. So might be better to find a complete LED fitting.

--
*Make it idiot-proof and someone will make a better idiot.

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

In article 6,
DerbyBorn writes:
My daughter has some under cupboard lights - about 3inch diameter
reflectors with a G4 bulb.

They fail frequently and I would like your advice on LED replacements.

LED Bulbs?

I assume you mean a G4 capsule used sideways, and not a reflector lamp.
They do exist but are not easy to find.
Kosnic produced them for a year and stopped because too little demand.
Then Verbatin produced them for a year and stopped because too little demand.

CPC have a no-name one now:
http://cpc.farnell.com/bltc/blmg440d...4-0/dp/LP08684

Check they will fit. Note you might be able to remove any reflector
because these LEDs don't need it.

New fittings that would work of existing transformer????

If it's an old magnetic transformer, yes.
If it's an electronic transformer, probably no because they won't
draw enough power to keep the transformer running. If you have several
of them, you might find they will work if all run from a single
transformer to generate enough load for it.

Replace the lot with LED Tape? (However, this would take 3 separate
lengths)?

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

On 18/03/2017 21:02, DerbyBorn wrote:
My daughter has some under cupboard lights - about 3inch diameter
reflectors with a G4 bulb.

They fail frequently and I would like your advice on LED replacements.

LED Bulbs?

New fittings that would work of existing transformer????

Replace the lot with LED Tape? (However, this would take 3 separate
lengths)?


I have been very impressed with LED tape for under cupboard lights... If
you buy a long length it can be cut into shorter sections.


--
Cheers,

John.

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

I have been very impressed with LED tape for under cupboard lights... If
you buy a long length it can be cut into shorter sections.


I guess my purpose would need 3 drivers.

In article ,
Andrew Gabriel wrote:
I assume you mean a G4 capsule used sideways, and not a reflector lamp.
They do exist but are not easy to find. Kosnic produced them for a year
and stopped because too little demand. Then Verbatin produced them for a
year and stopped because too little demand.

I had one of those desk lights with the transformer in the base which used
a G4. Because it was heavily used, lamps seem to needed replacement
frequently. Found an LED G4 replacement on Ebay - no idea of brand, but
wasn't cheap. Light from it was pathetic. So went back to halogen.

Couple of years ago, Lidl had LED desk lamps of about the same sort of
size. Multiple warm white LEDs. That's been just fine - and also barely
gets warm.

--
*The last thing I want to do is hurt you. But it's still on my list.

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

On Mon, 20 Mar 2017 09:59:35 +0000, Dave Plowman (News) wrote:

In article ,
Andrew Gabriel wrote:
I assume you mean a G4 capsule used sideways, and not a reflector lamp.
They do exist but are not easy to find. Kosnic produced them for a year
and stopped because too little demand. Then Verbatin produced them for
a year and stopped because too little demand.

I had one of those desk lights with the transformer in the base which
used a G4. Because it was heavily used, lamps seem to needed replacement
frequently. Found an LED G4 replacement on Ebay - no idea of brand, but
wasn't cheap. Light from it was pathetic. So went back to halogen.

Couple of years ago, Lidl had LED desk lamps of about the same sort of
size. Multiple warm white LEDs. That's been just fine - and also barely
gets warm.

I bought something similar from Aldi about a year or so ago. It uses a
20vdc wallwart to power its 4 watt's worth of LEDs in the lamp head
mounted on a couple of re-purposed telescopic aerials (same idea as the
12v 20W halogen bedside table lamp my wife uses). The base contains a
dense lump of concrete ballast with cut-outs for the DC jack socket and
the push-button on/off switch.

One night, I noticed that I could get a dim glow from the LED array by
touching one of the telescopic arms, the power most obviously, was coming
from the leakage current of the wallwart's EMI filter capacitor circuit
treating the DC 0v rail as a 'ground rail' despite the complete lack of a
metallic 'Earth Pin' (ie, the hi-Z half mains supply source of 'tingle
current' was providing just enough illumination to allow me to tell the
time from a Casio analogue display bedside alarm clock).

This gave me the idea of extending the lamp's function by wiring a 100K
resistor across the switch contacts so that it could also act as a very
dim 'night light' (just a little bit brighter than it was whilst lit by
leakage current alone) when switched off whilst still connected to its
wallwart power source[1] thus rather neatly capitalising on a key benefit
of LED over incandescent filament lamp technology, that of producing very
low levels of illumination with virtually no colour shift at current
levels so insanely low that not even the lowest wattage filament lamps
could produce light in the visible spectrum (infra-red, yes; Visible
light? No chance!).

[1] As is my usual practice with anything supplied with a wallwart PSU
(and mains voltage LED lamps), I check its operating consumption and,
more importantly for stuff that places its on/off switch *after* the
output of its wallwart PSU, its no-load power consumption.

I use a venerable Metrawatt analogue wattmeter for these tests since,
with the aid of a jeweler's loupe and the mirror backed 100W scale, I can
reliably interpolate down to quarter of a watt on sub 10 watt loads and
detect standby power drain levels down to a tenth of a watt or less[2].

In this case, the standby idle consumption proved to be undetectable,
meaning it was very likely less than 50mW. Improvements in standby
consumption efficiencies for modern smpsu wallwarts are showing up even
in those 5v 1A USB wallwarts that you can now purchase from Poundland.

[2] TBH, this just an educated guesstimate. I have yet to fabricate the
high voltage 576K ohm 100mW test load resistor required to see the actual
effect on the displacement of the needle from its zero set point with
such a low load.

Since it's a given that I'll see a definite twitch[3] when plugging a
wallwart in to the test socket due to the inrush charging current of the
HT rectifier pack smoothing cap or caps, I have to look for a deflection
from a steady state idle consumption reading that drops back down to the
zero point on the scale when I switch the wallwart off at (or unplug it
from) the mains socket.

[3] This is where an analogue wattmeter scores over the cheap 'n'
cheerful digital 'energy consumption meter'. It can do what no fancy
digital wattmeter can; it can show transient readings such as even the
most modest of inrush currents exhibited by low power DC voltage output
wallwarts as well as variations too small to be resolved on a digital
display limited to a resolution of a tenth of a watt at best. :-)

--
Johnny B Good