Rewire a table lamp - any help appreciated!

[Jacquiemalta]

Hi,

I have a table lamp that I love but it only allows bulbs up to 50 watt although the shade is large and open so not really a fire hazard. I have been using halogen bulbs to the equivalent of 70 watts (I think they're around 42 watt but I threw the box away) but they only last about a month before blowing. I have a feeling the fitting is dodgy because the bulb (bayonet) is never secure and rocks easily. Also, the switch which is part of the lamp holder, not on the cable, is dodgy too and needs playing about with a bit.

I want to rewire the lamp to take up to 100 watt bulbs and have been looking online at lamp holders. However from what I've been reading, the wattage is dependent on the shade, not the fitting. I'm not worried about the shade and would still like to use the lower watt bulbs equivalent to 70w anyway so the heat won't be too bad. Do I just need to replace the lamp holder with a new one and can I use the existing cable or do cables have wattages of their own?

I won't rewire the lamp myself as I work at a hotel and the maintenance team will do it.

Sorry if this is a stupid question to you professionals!

Thanks in advance for any help.

 

[Deleted member 9648]

Hi Jacqui. You can't get 100W bulbs anyway, good thing too, planet wrecking things. And remember that "Eco Halogen" is greenwash. There is no such thing as "Eco" Halogen, but others have given you some leads for LED bulbs so you should follow that up. You'll be looking for minimum ~950 Lumens in a warm white, which would probably be 10-12 Watt. .
If the bayonet fitting is dodgy, that can be replaced. "Lamp Parts" or some similar Google search will find what you need.
If the fitting is brass and it's an otherwise elderly metal lamp, then make sure the lamp is earthed. If it's old, then it's quite likely to not be. You may then need to replace the cable as well. 0.75mm three core. (And fancy braided stuff is also available in a huge range of colours). Make sure if you fit a new plug that you swap out the 13A fuse it came with it, and replace it with a 3A.
If in doubt about any of that, then get someone to fix it up for you and check it's safe

I would imagine 100w incandescent lamps are far less planet wrecking to manufacture than LED lamps....nobody seems to take into account that much of the 'planet saving' energy efficiency of LED lamps is offset by the less than planet saving manufacturing process.

 

[The Ghost]

A picture would be nice!

 

[rolyberkin]

LED lamp is the way to go, make sure you buy a good quality lamp holder if you are going to change it, loads of cheap Chinese crap out there, buy something good and it should be fine.

 

[Deleted member 9648]

A picture would be nice!

There you go mate.

 

[Jacquiemalta]

Thanks to everyone for your help. I'm in the UK next week so I'll speak to my dad about it too.

 

[dmxtothemax]

[Do I just need to replace the lamp holder with a new one and can I use the existing cable or do cables have wattages of their own?]

Well yes cables do have ratings, but unless yours is damaged by heat, it is unlikely to need replacing.
Just use CFL or LED and all these heat damage problems go away !
If the bulb socket is dodgy then just replace it.
Since your not doing it anyway, why worry ?
Let the trained people worry about that.

 

[NDG Elecs]

I would imagine 100w incandescent lamps are far less planet wrecking to manufacture than LED lamps....nobody seems to take into account that much of the 'planet saving' energy efficiency of LED lamps is offset by the less than planet saving manufacturing process.

That is like the ceramic mug vs the paper cup (you get from cafes) argument. You can make loads of papercups for the same overall energy input as one ceramic mug.

To the OP; if and when you buy the new lamp holder (the bit that is wobbly and has the dodgy switch), I would probably buy 2 or 3 slightly different types, as from past experience it can be a pain to ensure you are getting the right one. And at least you will only pay one lot of postage for them that way (and they are cheap). It may be a straight forward swap over but it may not..

 

[1Justin]

I would imagine 100w incandescent lamps are far less planet wrecking to manufacture than LED lamps....nobody seems to take into account that much of the 'planet saving' energy efficiency of LED lamps is offset by the less than planet saving manufacturing process.

Figures are hard to find, so let's make them up.. Just one 100W bulb will "emit" about 60KG of CO2 during it's 1200 Hr lifetime (UK typical power generation mix at 0.5 KG/KWh ) and cost £18 (~ 120 KWH) to run. Since the LED should last at least ten times as long, in it's entire 12000 Hr lifetime the LED "emits" a total similar amount, whereas lighting with ten new 100W bulbs changed as they fail, would have "emitted" in that time 0.6 tonne of CO2 and cost £180 to run.
Now I don't believe the "inbuilt" carbon footprint of LED is even remotely close to 0.6 tonne CO2, and if the manufacturers were spending £180 in power just to make it, then we wouldn't be buying them in the shops for £4.

 

[NDG Elecs]

I am an advocate of LED lamps, and have been since their emergence, and will continue to do so.

But they are a fair bit more complicated than a standard traditional incandescent lamp. They will likely have a much broader spectrum of 'ingredients' to make them. And when you factor in mining to get various ores and minerals out of the ground and subsequent processing, I can understand where Wirepuller is coming from.

I have no idea either way whether LEDs are greener than incandescents when ALL factors are considered.

 

[1Justin]

I am an advocate of LED lamps, and have been since their emergence, and will continue to do so.

But they are a fair bit more complicated than a standard traditional incandescent lamp. They will likely have a much broader spectrum of 'ingredients' to make them. And when you factor in mining to get various ores and minerals out of the ground and subsequent processing, I can understand where Wirepuller is coming from.

I have no idea either way whether LEDs are greener than incandescents when ALL factors are considered.

That's valid, and I'd like to see some complete cradle-to-grave figures. I can't find any, but if you do, let's see some
All we can easily get are energy as I outlined, and this is of course only part of the picture. But the figures are so persuasive it's hard to not to argue the benefit.
Anyone directly heating with raw electricity will need to dilute any of those with another guesstimate based on heating season. Ideally, the future is heat-pumps and massive reduction in all forms of heating (entirely possible and absolutely necessary) which add validity back into the basic energy argument though.

 

[Octopus]

Re the "green" credentials of LED lamps - if they are made in China then they have the "footprint" of the manufacturing and we have the benefit of the lower power requirement.

Gordon Brown used to refer to this as "importing deflation" when he lauded importing cheaper goods...

 

[Deleted member 9648]

My post regarding the alleged planet saving LED lamps was slightly tongue in cheek TBH, I have no more idea than anyone else as to how much impact manufacturing these lamps really has. I do suspect though that the benefits are not as great as we are 'LED' to believe....(see what I did there!)

 

[freddo]

It's a shame many of them are lasting nowhere near their rated life.

 

[telectrix]

nobody seems to have considered the heat output of a 100watt filament lamp. it apears on gthe face of it to be wasted energy, but the heat is not exactly a waste. it warms the ambient air, thus making less energy requirement from the centaral heating.

 

[1Justin]

It's a shame many of them are lasting nowhere near their rated life.

I think that's where brand quality comes in, and I agree, I have had failures.
The differences are quite clear with the approach taken by the more commercially orientated downlight and spotlight manufacturers compared with "domestic" brands.
But for light bulbs, which are still seen as consumables even in LED world, the brand/quality effect might be less clear cut, since there just isn't as effective a heatsink, and there is hardly any space for the driver. All manufacturers just have to live with that fact.
LED lifetime is inferred from statistics taken at elevated temperatures with the products running in ovens, crunching the statistics up to get a predicted lifetime is bound to result in some adventurous claims for those manufacturers who are in a hurry to get cheap and cheerful products onto the shelves.