Connectors blocks to reduce cable size for 12v lights

[hunggaur]

Hi folks in the process of installing a set of 12v spot lights, each one has a transformer.

Th connector for the cable will only take a single 1.5mm cable. Therefore to jump from one transformer to the next with the 240 ring the 2 cables making the loop need to drop down to a single cable as the transformer will not take both cable.

My question is:

What is the best way to reduce the cables should I bring the 2 cables in to a connector block and one cable our

Or

Use a crimp connector crimping 2 cables one end and one the other.

Or

Is there another way it could be done.

All cables will be located in the loft and not accessible by anyone.

Also all the wiring will have to be signed off by building control so I need to make sure it meets current regs.

Any help or advice welcomed

Cheers

Job

 

[EFLImpudence]

Use 1mm².

Don't use junction boxes or unnecessary joints.

 

[hunggaur]

Use 1mm².

Don't use junction boxes or unnecessary joints.

Even if we used 1mm cable there would not be enough room inside the transformer connector to take 2 x 1mm cables so they will have to be jointed and reduced in some way.

 

[EFLImpudence]

There must be.

 

[hunggaur]

There must be.

No the connector in the transform where the cables connect into the unit is a micro connector which will take a maximum of a single 1.5mm cable so 2 x 1 mm cables will simple not fit.

 

[EFLImpudence]

I'm tempted to say they are therefore not fit for pupose.

Are they really cheap foreign stuff?
Do they have cable restraints?


You could use some of THESE but there will be a lot of joints.


Have you already bought the lights?
If not, what about 240V lights.

 

[winston1]

Use one larger transformer for all the lights. There is no necessity to use a separate transformer for each.

 

[DaftPunk]

Except for if the transformer fails you loose all your lights, and the problems of VD when running ELV over any sort of distance. Oh and the siting of the transformer somewhere accessible and the inrush current too.

 

[ericmark]

Like others I question today why use 12 volt? Years ago the quartz halogen lamp running off 12 volt lasted longer than those running off 230 volt and were slightly brighter plus using electronic regulation the lights lasted even longer.

However times have changed. The electronic controlled transformer will not in the main work with LED lamps and at 12 volt cold cathode lamps will not run so in the main using 230 volt gives far more latitude when selecting lamps allowing a gradual change from tungsten to low power lamps as tungsten is withdrawn.

The transformers do tend to come in two packages those designed to be used inside a fitting and the stand alone type. The latter will have a cable clamp the former will not and therefore need to be mounted inside some sort of box which will require a key or tool for access.

These already linked to have three cable clamps the one shown here uses maintenance free contacts so you can fit where it can't be assessed on the 10 year EICR which we all know is rarely done.

Often the transformer designed to be used inside a fitting has no earth connection those for independent use will normally have a place for the earth wire even if not used by that fitting so it's there for future use.

 

[OwainDIYer]

You could use some of THESE but there will be a lot of joints.

These are cheaper and I think smaller to fit through holes

http://www.tlc-direct.co.uk/Products/TLCT101C.html

But it's an unnecessary faff when simply choosing a better transformer with mains input terminals that are actually usable would be better.

 

[securespark]

Post a picture of the transformer and a scan of its instructions.

 

[winston1]

Except for if the transformer fails you loose all your lights, and the problems of VD when running ELV over any sort of distance. Oh and the siting of the transformer somewhere accessible and the inrush current too.

Taking your points in turn.

True transformers rarely fail, in fact I've never known one to fail.

Using the right cable for the distance will eliminate voltage drop.

Siting, well maybe, maybe not difficult.

Inrush current for one larger transformer should be no more than several smaller ones in parallel surely.

 

[DaftPunk]

Yet again this is where your lack of experience shows. I've been to many jobs where a 250VA transformer will trip a B6 circuit breaker upon switching it on but never had the same problem with 10no. 50VA transformers.

 

[333rocky333]

True transformers rarely fail, in fact I've never known one to fail.

Untitled

• 333rocky333
• 28 Sep 2008
• 1

Untitled

• 333rocky333
• 28 Sep 2008
• 1

Untitled

• 333rocky333
• 28 Sep 2008
• 1

Untitled

• 333rocky333
• 28 Sep 2008
• 1

 

[333rocky333]