led light for bathroom floor

[bathroomblues]

First time on here so gently and slowly please
I have three 35ma led floor lights that I want to place into the floor in front of a new bath. There is plenty of room under the floor boards for wiring etc. The led lights have two wires, one red, one black. I know this sounds like the old mains colour code but I would be very surprised if they had to connect directly to the mains and I expect that would be against the electrical regulations anyway being so close to a bath. As far as I can google it seems that I need a led driver but thats as far as I can get because there seems to be a bewildering array of them. Additionally am I actually allowed to do this work myself? Happy to get an electrician in but just wanted to get the facts first.
Many thanks

 

[flameport]

The lights require a constant current driver. Are you sure they are 35mA - 350mA would be more likely.

You can install them yourself, doing so is notifiable work and therefore involves paying building control fees which would typically be £100 upwards.

 

[automationman]

Do a search for “constant current LED drivers” and you will see what you need. You will need one that will support 3 LEDs which is quite common. The driver must be located in a position where it can be inspected/replaced in the future and not covered in thermal insulation or anything similar. The red and black wires that you mention must not be connected to mains (230VAC) LEDs operate on just a few volts of Direct Current (DC) An LED light is essentially just a diode (a one way valve in plumbing analogies) that has been tuned (doped) to emit light in the visible part of the spectrum.
So it will only emit light when connected in the right direction (forward biased)
The red wire is the ANODE connection which connects to the driver connection marked (+) or positive (or rarely ANODE) The black wire is the CATHODE connection which connects to the driver output connection marked (–) or negative (or rarely CATHODE) You have three LEDs so wire them in series (and polarity) as follows:
Positive on driver output – to – red on LED1.
LED1 – black – to red on LED2.
LED2 – black – to red on LED3.
LED3 – black to Negative on driver output.
Assuming you are refurbishing your bathroom - a fair assumption, I think, given your user name 
Then I recommend that you install a single electrical accessory backing box into a wall adjacent to the bath (at a height of about 450mm from the floor and a distance such that it will not get splashed )
Have a mains supply enter the box which would be switched from your lighting circuit (I am assuming you want the LED floor light to switch on/off with your main bathroom lights)
Your LED wiring (which can be good quality bell or speaker wire) would then run under the floor and up inside a small chase in the wall to the backing box. In the backing box you will then have a switched mains supply (from your main lights) and the connections to the LEDs (wired in series)
You then wire the mains connection to the input (primary) of the driver and the LED wiring to the output (secondary) of the driver. It is VERY important that the backing box (if metal, is earthed by connecting the switched mains supply earth to it inside the box. You then place a blanking plate over the front of the box (you can buy blanking plates at most of the “sheds”)
Your question about you doing the work is very appropriate because you probably should not unless you are very familiar with current (17th edition) wiring regulations, electrical safety, electrical theory, have access to appropriate test equipment, able to certify the work, pre-notify your building control and have them inspect the work on completion (for a charge)

 

[RossR]

Technically, you could do this yourself. However, as flameport says, it would cost a lot to notify building control. I'd recommend going the electrician route. just make sure they are registered with a competent person self certification scheme (Elecsa, NAPIT or NICEIC) They can notify for about £1.50.

 

[bathroomblues]

thank you all very much for your helpful replies.
automation man thank you for taking the time to offer so much detailed and helpful information. I have spoken to a local electrician today who agreed to do the work for me and in the way you have suggested. His one question is do you have a specific led driver in mind that would fit inside the electric junction box ? Also my bathroom light switch is a dimmer - will this be a problem? I can change it for a normal switch if needed.

 

[automationman]

I often use the following:

HEP LIVC41-UNI CONSTANT CURRENT 350ma DRIVER
Available from EDIT (NOT SURE IF I AM ALLOWED TO STATE A COMPANY NAME ON THE FORUM) so if you google for cube lighting with that part number then you will find the company.


Dimensions (MM) 50X35X20 so they fit easily inside a single gang 35mm deep backing box.

That particular driver operates from 100VAC to 230VAC and will work well with a good quality dimmer. It will not dim the LEDs but will switch the LEDs on and off as required while allowing you to dim the existing bathroom lights.

Hope that helps