Led strips on shelves

[23vc]

Hi
I'm making some hollow mdf floating shelves in an alcove, probably 4 shelves in total, I want to put led light strips on the back of each shelf shining against the wall, I can fit the wiring/transformer inside each shelf, and there will be a 13a socket at the bottom of the alcove. I'm also doing the plastering so the wall is back to brick so I can chase whatever wiring into it.

However other than this I'm massively struggling to work out how best to do this, what kind of cable, where to transform it down to 12v ( IE inside each shelf or down at the bottom by the socket).

If anyone's done similar (eg. Like a kitchen but with multiple 1m strips about 60cm apart ) I'd be really grateful for any advice!

Cheers
John

 

[333rocky333]

We do a similar thing in shops, but use 240volt fittings like these
http://www.linolitedirect.co.uk/Linolite/Sylvania-LS-LED-Range_2

 

[23vc]

Thanks for that, so that would be an option but looking at about 40 quid a shelf which will likely blow the budget unfortunately, hence was trying to do something with the strip tape and either a transformer in each shelf (one which does not come integrated into a 3pin plug obviously) or a single transformer for all shelves, but I know I need to be careful with how many strips/cable size doing that.
Ideally I'd run say 1mm 2 core up the wall looping into each shelf to a transformer wired to a 1m strip, unless I can use a single transformer for the lot, but I'm a bit clueless on what kind of cable I'd need for that
Cheers
John

 

[winston1]

Well for a start you can't use a transformer. LED strips require 12 volts DC and transformers are AC devices. You need a 12 volt DC power supply, only one, at the bottom where your 13 amp socket is. Run separate feeds from it to each LED strip. They don't take much current so flat twin flex is all you require plus soldering skills to attach it to the strips.

 

[23vc]

Thanks v much
When you say twin flex would 0.75mm be OK? Heard there are issues with voltage drop which I don't claim to fully understand, but I think that's more or you're Daisy chaining them?
Cheers
John

 

[deadshort]

Hi, i have my drivers in the shell of my mdf shelve with access from under by removing the bottom panel on the bottom shelve. All 4 drivers are located together, i used 0.75 flex with no issues.

Regards,

DS

 

[motorbiking]

I looked at this option for my kitchen and ended up using a mini led tube light. cheap enough and no mucking about with drivers. only downside is they are quite bright.

e.g. https://www.tlc-direct.co.uk/Main_Index/Lighting_Menu_Index/Ultra_Slim_KBU/index.html

25mm X 36mm complete with switch.

 

[SFK]

John,
I have done similar to "multiple 1m strips about 60cm apart".
I used this light strip (note: i found this too white for me)
https://www.amazon.co.uk/gp/product/B007O4I34U/ref=oh_aui_search_detailpage?ie=UTF8&psc=1
which is "4.8Watts per meter" <<< this is the critical information to find.

So if you need 5m of LED to be illuminated you need a "LED Driver" that is at least capable of providing 24Watts (I would always add on more than 24% so the Driver is not running at its maximum output).
So for example for 5m of 4.8W/m LEDs use a 50W LED driver from here: https://www.amazon.co.uk/s/ref=nb_sb_noss_1?url=search-alias=diy&field-keywords=led+driver

I kept this transformer near the socket and used good speaker wire to transfer the 12V from the LED driver to the LED strip.
I soldered the wire to the strip, or used flat white connectors (which have to match the type of LED strip you bought above):
http://www.ebay.co.uk/sch/i.html?_f...ed+connector.TRS0&_nkw=led+connector&_sacat=0

For under the counter I went:
PLUG > Wire > LED Driver > Speaker Wire > LED Strip > Speaker Wire > LED Strip > etc etc

For under shelves I went:
PLUG > Wire > LED Driver > Speaker Wire > LED Strip (under shelf 1)
> Speaker Wire > LED Strip (under shelf 1)
> Speaker Wire > LED Strip (under shelf 1)

Notes
- If the connecting wire and lengths of LED gets too long then voltage drop becomes an issue and the furthermost LED get dimmer.

sfk

 

[23vc]

Thanks guys that's v helpful
So I think as long as I run some individual runs of 0.75mm flex from the bottom up to each shelf, it will keep my options open to most likely do the strips like SFK says.
If I use a single transformer at the bottom, can I run flex to a standard round JB then the spurs off that to each shelf (IE all 12v and 0.75mm flex)
Cheers

 

[SFK]

.75mm2 flex is much bigger than you need as many use that thickness for long 12V runs to their pond without voltage drop issue. But if you have it and can hide it use it. Otherwise speaker wire is perfect. Likewise a round junction box is bigger than you need. A choc block connector would do just as well.
So all sounds good. And a single 12V cable spouting into a star is good.

One item I forgot. Many of the LED tapes with double sided tape backing seem to not be sticky enough. So i used a hot glue gun every roof or so to ensure it did not fall off.
Sfk

 

[winston1]

Thanks guys that's v helpful
So I think as long as I run some individual runs of 0.75mm flex from the bottom up to each shelf, it will keep my options open to most likely do the strips like SFK says.
If I use a single transformer at the bottom, can I run flex to a standard round JB then the spurs off that to each shelf (IE all 12v and 0.75mm flex)
Cheers

As I said you CANNOT use a transformer as transformers are AC devices and LED strips require 12volts DC. You need a 12 volt DC power supply.

 

[23vc]

Thanks guys that's spot on
Winston1 yes sloppy terminology sorry I'll be more thorough when I come to actually buying the stuff
Cheers

 

[333rocky333]

As I said you CANNOT use a transformer

stop being a tit.
Take a hint

Thanks for the reply! I'll admit that seeing Winston1's reply did put me off (from the forum) somewhat

 

[winston1]

stop being a tit.
Take a hint

You are being a twit.

Transformers give out AC.
LED strips require DC.

END OF.

 

[EFLImpudence]

Genuine query.

As a matter of interest, Winston, why is that the case?

I realise you are right according to the definition given but could it be that the definition is out of date?

Why cannot something transform 230VAC to 12VDC?
Transform means to change something therefore transformer is merely something that changes something else.
Is your definition just out of date and it has been superseded by the modern world?


If that is out of the question then what does the apparatus do (what verb) when 230VAC goes in and 12VDC comes out?

You can say it is a switched mode power supply but the voltage hasn't been "switch-mode-power-supplied" has it?