Use a mains 240v outdoor light on 12v?

[SkipFeeney]

Hi All,

A long story but is it possible to use an outdoor 240v light fitting with 12v?

Eg buy one of these transformers: (its for indoor use)

http://www.maplin.co.uk/p/60w-low-voltage-lighting-transformer-nl50e

and buy one of the these bulbs:

http://www.amazon.co.uk/dp/B003TKS1...m=A3P5ROKL5A1OLE&pf_rd_r=132GAPA497ESQ792KTX3

Will it work, is it safe?

Thanks

 

[ban-all-sheds]

Will it work

No.

Also, how long would the cable be between transformer and lamp?

is it safe?

Don't see why not, but it's irrelevant.

More alsos:

Why does the advert say 20W when the lamp packaging only admits to the existence of 5,7,9 & 11W ones?

Why does the advert say, and the photo show, an E27 base lamp when the packaging says it's a B22?

Given those two discrepancies, and the fact that it's an unknown Chinese make, why do you think it's going to be anything other than a short-lived unreliable POS?


And finally, why? If you want a CFL, why not fit a 240V one and avoid all the messing about with transformers and possibly larger cable?

 

[Taylortwocities]

That will not work. Those particular lamps are meant for use on true DC supplies, read the product description.
Also that "transformer" will not provide you with DC. It is actually a switched mode power supply, designed to drive 12v halogen lamps and needs a load of at least 35watts, and that bulb in your link is only 20watts.

I know you said

A long story

but you need to explain what you are trying to achieve.
Even the title of the topic is confusing

"Use a mains 240v outdoor light on 12v?" Did you mean, supply a 12v light with 240V, maybe?? More info, please

 

[ericmark]

If you only have 12 volt then use a 12 volt bulb. These 10 ~ 36 volt bulbs are designed for use with a battery.

 

[SkipFeeney]

Thanks for your help - I will explain more...

I have got 6 240v outdoor lights I bought in a sale a while ago. Looking at the garden and where the CU is its going to be very difficult to wire up some armoured cable and also dig out a suitable size trench for the cable. I also don't want to put the cable in conduit. What I was thinking potentially is to use some 12v transformers situated inside and use low voltage wire going outside and 12v bulbs in the light fittings.

Is that possible?

 

[ban-all-sheds]

1. The cable needs just as much protection.
   
2. Voltage drop is a much bigger factor to consider at extra low voltage, as it's absolute, and therefore a much higher %.
   
3. FYI: [wiki]Electrics%3AVoltage-Bands[/wiki]

 

[JohnW2]

Voltage drop is a much bigger factor to consider at extra low voltage, as it's absolute, and therefore a much higher %.

Actually a lot worse than you imply, since even the absolute drop (let alone the % drop) will be much higher at ELV, because of the much higher current (for a given power).

Kind Regards, John

 

[SkipFeeney]

So it is possible?

But I will need to keep the cable runs short to watch the voltage drop, dig a trench for the cable, use a different transformer and some better bulbs

 

[JohnW2]

So it is possible? But I will need to keep the cable runs short to watch the voltage drop, dig a trench for the cable, use a different transformer and some better bulbs

I'm not really sure how you see that as an advantage over just being conventionally and sticking with 230V (in which case most of those issues would disappear). What sort of cable do you plan on burying? You can't (shouldn't) just bury 'naked' flex, even if it's only carrying 12V.

Kind Regards, John