SMD, LED, High Power LED - Advice needed

[jamesdean1986]

I have 14 new GU10 recessed ceiling lights in my kitchen currently using 50w halogen bulbs.

I'm looking to switch to SMD or LED but variation in specifications, design and prices are causing me to question what I need.

I think I understand the basic difference between SMD and LED but then different sites give different wattage equivalents. Some say 4-5w equals 50w, but other say 7W. And the variation in output angles drastically changes.

I'm probably going to be ordering 20 of these as I have some lights on the front of the house I'm also replacing.

On ebay I can get 20 unbranded 48SMD bulbs for around £50, but elsewhere I'm looking at over £100. For 20 branded bulbs im looking at over £200.

Any advice or experience is welcome.

 

[phatboy]

First off, don't go with unbranded eBay ones - I got some and they weren't CE marked, and I was very skeptical that they had any sort of fuse/cutout.

SMD's have a very wide beam angle, so have excellent coverage. My only gripe is they look a bit ugly.

I also found everyone says different things about wattage equivalents. I replaced a load of 50w halogens with 3.5w LED's, and they aren't quite as bright, so I'd say 4w is about the same in LED as 50w in halogen.

I bought all mine from lightrabbit.co.uk - I recommended them a few times on here, but I promise I am not affiliated with them! Just that they have their UK office in Jersey so I can go into their shop and buy that way.

 

[jamesdean1986]

Thanks very much.
Any idea why some have fins around the bulb and some do not. I assume the are for venting or heat distribution but not 100% sure. The more expensive bulbs seem to have them but wondering if they are a gimmick as these bulbs do not get that hot.

 

[phatboy]

It's definitely for cooling, although ones without this aren't necessarily bad, as some of mine have big heatsinks on the back.

Noticed that SMD bulbs don't have them, so I guess they run cooler than LED's....

 

[ban-all-sheds]

I have 14 new GU10 recessed ceiling lights in my kitchen currently using 50w halogen bulbs.

Do you need 14 lights in your kitchen because it is enormous?

Or do you need 14 because you've chosen lights which are useless at actually lighting up rooms?

 

[phatboy]

I have 14 new GU10 recessed ceiling lights in my kitchen currently using 50w halogen bulbs.

Do you need 14 lights in your kitchen because it is enormous?

Or do you need 14 because you've chosen lights which are useless at actually lighting up rooms?

Or the house was like that when he moved in?

 

[jamesdean1986]

Its a long story but we had 6 initially installed then decided to have more installed due to dark spots. It is slight overkill but there were dark areas we needed lightening and if we just had those areas done it would have looked strange. We probably only needed 4 extra but to keep things uniform with the existing ones we needed 8. But i have split them over 3 switches.

 

[ban-all-sheds]

Its a long story but we had 6 initially installed then decided to have more installed due to dark spots.

Why wasn't 6 enough?

Was it because the room is very large, or because the lights you chose weren't actually any good at the job you wanted them to do, i.e. light up the room?

 

[jamesdean1986]

The kitchen and utility is quite large and its not a standard square or rectangle

 

[WhydidIstart]

Just to add that SMD means Surface Mount Device and is referring to LEDs that are Surface Mounted.

So SMDs are LEDs, just that you tend to get 20 - 60 of them in one GU10 unit, as opposed to normally getting 1 - 5 'regular' LEDs in non-SMD LED lights.

 

[jamesdean1986]

I done a fair bit of research on the difference between them and the pros and cons. But couldn't find much about high power LEDs

 

[phatboy]

SMD - Surface Mounted Diode, so not LED's but a newer technology!

 

[bernardgreen]

SMD = Surface Mounted DEVICE, can be any type of component , resistor, capacitor LED ( ligh emmitting diode ) .

Surface mounting meaning they are soldered to copper on the surface of he board.

THD = Through Hole Device which are fitted to the board by leads through holes in the board and soldered to the copper on the underside of the board.

A particular component can be produced as SMD or THD so the same LED die ( the active bit ) can be packaged as SMD or THD.

THD can be written THM ( Through Hole Mounted )

SMD devices tend to be the lower power device because there is little copper area to disapate heat while leaded devices (THD) have better heat disapation into the copper of the PCB.

An overheated SMD can un-solder itself. An THD will remain in place.

 

[SimonH2]

SMD - Surface Mounted Diode, so not LED's but a newer technology!

WRONG. SMD = Surface Mounted Device, which is a standard designation in electronics. They are LEDs, and are not a "newer technology".
EDIT: The LED inside the package is exactly the same, only the packaging is "newer".

There tends to be three types of LED lamps available.

Some have lots of "old fashioned" leds which have plastic moulded housings with wires sticking out the back which go "through hole"s in the circuit board. Each LED is low power, so there needs to be a lot of them for any decent light output.

Then you have essentially the same thing but using SMDs. The SMD devices are a bit smaller than the through hole LEDs, and are cheaper to assemble (no holes to drill in the board).

Lastly, pretty well all the "high quality" lamps use one or more "high power" LEDs - sometimes referred to as light engines. Some of these high power LEDs can get up to 3W or more in a single device (state of the art keeps advancing all the time - it's not long since 1W was considered top of the range.

For all types, thermal control is vital. Many of the cheaper types simply bung a load of small LEDs on a circuit board - with, I suspect, little or no consideration of thermal design. I can't help thinking that this is an issue with the reputation cheap LED lamps have for poor reliability.

 

[RF Lighting]

To properly replace a 50W halogen you need to be aiming for around 7- 8 watts.

I currently pay about £12 for a 5W lamp which are not quite as bright, but are a good compromise of output Vs cost.