DIYer has a lamp wiring question

[brgrt2T]

I’m a DIY’er. Or at least, if I have an electrical problem, I like to fix it myself. I couldn’t find an answer to my question after googling around a bit, and no electrician would give me an answer, so I thought I would try your forum. An answer would be greatly appreciated.

I have a desk lamp wired for 120 volts. It uses two 50-watt, bi-pin halogen flood bulbs. The bulbs are expensive and burn out quickly. And no LED bulb exists for my specifications. So I was thinking of rewiring my lamp for 12 volts, because 12-volt bulbs offer more options and are cheaper. The lamp can’t be taken apart, so I’m thinking of adding a transformer plug and splicing the two wires under the base. Is any of this feasible? I’m attaching a photo of the lamp.

Thanks,

Tamara

 

[littlespark]

I would say no, not feasible. You may not find a 12v lamp that has the same pin configuration as that in the lampholder.
Most lamps I know of have an LED equivalent. Is there a rating plate that shows the max W or a make/model/ serial no.?
It is certainly possible to cut the cables in the base and insert a transformer if there is enough space in there for it, but the problem with the lampholders still exists.

 

[DPG]

Can you post a picture of the bulb. As above, I'd be surprised if there is no LED alternative available.

And before anybody starts going off on one about me calling it a 'bulb', I am doing this intentionally to differentiate it from the 'lamp' as a whole.

 

[brgrt2T]

I would say no, not feasible. You may not find a 12v lamp that has the same pin configuration as that in the lampholder.
Most lamps I know of have an LED equivalent. Is there a rating plate that shows the max W or a make/model/ serial no.?
It is certainly possible to cut the cables in the base and insert a transformer if there is enough space in there for it, but the problem with the lampholders still exists.

Hi,

I did find a 12v bulb with the same GU5.3 base (all the specs are identical between the two bulbs). And no, no 120-volt LED equivalent exists. There is a 12-volt LED, but with a different socket.

So, is rewiring the lamp for 12 volts really as easy as splicing the wires and adding a transformer plug? Is there anything more I need to know to make the lamp operational and safe?

Thanks,

Tamara

 

[brgrt2T]

Can you post a picture of the bulb. As above, I'd be surprised if there is no LED alternative available.

And before anybody starts going off on one about me calling it a 'bulb', I am doing this intentionally to differentiate it from the 'lamp' as a whole.

 

[brgrt2T]

Here are images of the two bulbs. The Bulbrite is the 120 volt. The Eiko is the 12 volt.

 

[telectrix]

if you can physically fit the 12V bulbs in the lamp, then id fit 12V LED bulbs and connect via a LED driver that likes 120V input.

 

[brgrt2T]

if you can physically fit the 12V bulbs in the lamp, then id fit 12V LED bulbs and connect via a LED driver that likes 120V input.

I can't replace the socket, so I can't use LED bulbs.

So will adding the transformer and splicing the wire work? You don't seem to take to this idea. Is that right?

 

[Richard Burns]

There should be no particular problem with reducing the incoming voltage to the light fitting from 120Vac to 12V.
There should also be no problem with using LED bulbs in the fitting as they would be designed to the same physical size in many cases, this would save energy but would mean you would be best to obtain a 12Vdc LED driver instead of a 12Vac halogen transformer.
The critical point is to ensure that the connections you make to install the driver/transformer are safe, secure and enclosed and that the cable will not be able to be pulled out of the connections.

 

[telectrix]

those lamps in post #7 are MR16 base. sameas this LED
Philips CorePro LED spot ND 5-35W MR16 827 36D - http://theledspecialist.co.uk/philips-corepro-led-spot-nd-5-35w-mr16-827-36d-1791.html

 

[littlespark]

The OP is in America. Of course we can get LED equivalents in this country, but Trump has banned importing.
LED’s are also energy saving, and Donald Duck over there doesn’t believe in fake news global warming ... (tiny, tiny hands!!)

 

[brgrt2T]

I can't replace the socket, so I can't use LED bulbs.

So will adding the transformer and splicing the wire work? You don't seem to take to this idea. Is that right?

There should be no particular problem with reducing the incoming voltage to the light fitting from 120Vac to 12V.
There should also be no problem with using LED bulbs in the fitting as they would be designed to the same physical size in many cases, this would save energy but would mean you would be best to obtain a 12Vdc LED driver instead of a 12Vac halogen transformer.
The critical point is to ensure that the connections you make to install the driver/transformer are safe, secure and enclosed and that the cable will not be able to be pulled out of the connections.

Hi Richard,

You're right. I did find a perfect LED match for my halogen bulb, except for one thing. The LED bulb is white, and I need a silver one to match my lamp. The bulb is a visible part of the lamp, and its seating is silver. I even think this lamp was designed for a halogen bulb, since the colored light given off by the body of the bulb seems to be part of the look of the lamp (You can see a photo of the lamp in an attachment to an earlier post). I see the benefits of getting an LED, but I would like it to be silver.

It's time consuming finding the right bulb, since googling the specs will return anything and everything. Perhaps you can suggest some large LED bulb manufacturers, and I could try tracking down a bulb through their websites.

Thanks,

Tamara

 

[Richard Burns]

Perhaps something like this would suit?
Most LEDs tend to be flat white or heat sink corrugated silver, though some from China have flat matt silver backs, occasionally as the link above shows they are silvered glass.
I am not familiar with the suppliers you may have available to be able to recommend anyone in particular.

 

[telectrix]

get a white one and stick some kitchen foil on it. .

 

[DPG]

I think I'd just go and buy a new led lamp to be honest. Easier in the long run. Unless this thing has sentimental value or something.

 

[telectrix]

must have sentimental value, as it has the aestetics of a demented toad.

 

[brgrt2T]

Perhaps something like this would suit?
Most LEDs tend to be flat white or heat sink corrugated silver, though some from China have flat matt silver backs, occasionally as the link above shows they are silvered glass.
I am not familiar with the suppliers you may have available to be able to recommend anyone in particular.

Thanks Richard for the link. It's the right bulb. I even found one in warm white, which is the color I prefer. But now here is the real deal breaker. The bulb comes in a pack of six. And that makes no sense for me, because I don't need these bulbs for anything but my lamp. Unless there is some way to buy just two, without paying a premium, I'm stuck with the halogen bulb.

 

[Richard Burns]

Since you appear to want to use halogen lamps, then use halogen lamps. It is an easy solution and does not cause problems with transformers, dimmers, etc.
Be aware that you will be using approximately 90% more energy and that from about 2020 the halogen lamps will be unavailable following the energy efficiency measures applied by congress.
Cheapest LED I could find at 3000K not 2700K warmish but not as warm as halogen.

 

[brgrt2T]

Since you appear to want to use halogen lamps, then use halogen lamps. It is an easy solution and does not cause problems with transformers, dimmers, etc.
Be aware that you will be using approximately 90% more energy and that from about 2020 the halogen lamps will be unavailable following the energy efficiency measures applied by congress.
Cheapest LED I could find at 3000K not 2700K warmish but not as warm as halogen.

Hi Richard,

That's strange. The 5000K is offered as a single, but the same bulb at 3000K is offered only in a six-pack. I'll call the company tomorrow and see what my options are and how much the six-pack costs.

The reason I'm a bit wary of using the LED is that, in my experience, they are never as bright as the incandescent or halogen bulbs they supposedly comparable to. The halogen bulb I have now is 595 lumens (x 2, since I use two bulbs). The lumens of this LED bulb is only 500. And it has a 6.6 wattage, which is less than the 7 watts of the white LED that was originally suggested here.

How much of a difference do you think the 190 Lumens differential makes? It may still not be an absolute deal breaker for me, because the wattage is still higher than the 35 watt halogen bulbs I originally had in my lamp, which I found a bit dim.

Thanks,

Tamara

 

[Squid]

Can you post a picture of the bulbs.