Which wire and connectors ?

[FerritVIP]

Hi everyone,

I've been searching the internet but can't find or understand what I need so I hope somebody can help

I am adding some new 12v lights under my cupboards in the kitchen, they going into a 12v transformer which I already have 2 lights running off. The problem I have is that the wire from my lights is to short so I need to extend these. What wire do I buy? I've looked at 12v wire but it's all different thickness and ampage and I'm truly stumped ? Also can I use crimp clips to secure the wires together or do I need some electrical blocks ?

Sorry if I'm sounding dumb but better to ask than waste money or cause a explosion lol

 

[bernardgreen]

Not enough information

How many new lamps ?

What wattage are the new lamps ?

What wattage are the existing lamps ?

What does the transformer label say for it's

Maximum load in watts ?

Minimum load in watts ?

 

[FerritVIP]

Sorry about that
I've looked and have the following info

3 new lamps per transformer so 4 in total per transformer
New lamp wattage is 10w per light
Existing lamps are 10w
One the transformers it says total load max 30v 10A
Max current 3A per outlet
240v to 12v
10w-20w

Hope this helps

 

[bernardgreen]

One the transformers it says total load max 30v 10A

That is bit odd, It would make sense if it was a variable power supply with adjustable voltage.

240v to 12v

OK

10w-20w

So 20 watts maximum load. therefore 4 lamps at 10 watts each will overload the transformer. You need more transformers or change to a transformer rated 10w-40w.

( they are not true transformers, they are power supply units )

 

[FerritVIP]

Dam it I'll have to change to transformers.

What wire would I need to get also ?

 

[bernardgreen]

A 10 watt lamp at 12 volts pulls 0.833 amps.

Call it 1 amp per lamp

If the wire is taking current to 4 lamps it needs to be 4 amp ( use 5 amp )

The other consideration is volt drop along the cable ( a little voltage is lost pushing the current through the resistance of the cable.

For a couple of metres of 5 amp cable the voltage drop can be ignored.

5 amp terminal blocks

will be OK

make it look a bit neater if you use

 

[FerritVIP]

Excellent thank you so much

Is this the sort of transformer I'm looking for ?

60W 12V Halogen LED Lamp Electronic Transformer Power Supply Driver Adapter

 

[FerritVIP]

I can only find wire that is at least 21 amps is it ok to use that ?

 

[JohnW2]

One the transformers it says total load max 30v 10A

That is bit odd, ...

Extremely odd, in fact, given ....

10w-20w

I wonder if something has been mis-read?

Kind Regards, John

 

[FerritVIP]

Hi john, I don't thinks it been mis read as there are only two distribution slots and I was to add more lol thought it would be ok but thought it was strange there only 2 fitted.

 

[JohnW2]

Hi john, I don't thinks it been mis read as there are only two distribution slots and I was to add more lol thought it would be ok but thought it was strange there only 2 fitted.

I'm still pretty confused - not only is 30V far more than you need for your 12V lights (it would probably 'blow them up'), but 10A at 30V is 300W, a lot more than the 10W-20W rating at 12V which is mentioned! I guess there's something I'm not fully understanding.

Kind Regards, John

 

[Belboz]

OP - take a picture of the label and post it one here please.

 

[FerritVIP]

Here is the transformer and distributer

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• FerritVIP
• 24 Aug 2014
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• FerritVIP
• 24 Aug 2014
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[Belboz]

Looks like that is for either one 10W lamp or two max. (20W)

As stated, you need to get another transformer which is rated for the output you require (number of lamps x their wattage)

I am assuming you only want more cable (wire) for the 12v output and not the mains input??

 

[Taylortwocities]

OK. The second picture is just a connector bar, so the 30v, 30A, 10A per outlet stuff just relates to the connector.

The first picture is of a 12v nominal transformer. But it seems to be only capable of delivering up to 20watts, so you'll need tobuy one thav is good for at least 40watts.

The most common type is a 60watt transformer. Get one of those and you are good to go.

A cable with a CSA of at least 0.75mm² will be fine.