12V outdoor lighting

[brucecampbell]

Hoping to get some clarity please.

I have 6 conductor/wire security cable running all over the entrance to my property.
In some places I only use 2 or 4 of the wires for a motion sensors and reed switches;
So, I have decided to use the remaining wires to add further lights to the driveway and surrounds.

I'm pushing power down 2 wires from a 12V 5A transformer.
I hooked up 5 x 5W LED lights.
2 work, 3 don't
So I get the volt meter on and it shows I only have 6 Volts coming.

The two which work are the same brand, the three which don't are a second brand.

So I am assuming the voltage is too low to power up these other three.

Question is - Am I doing any damage to LED's or transformer by using such small gauge wire?

The cable in question would be around 60-80mtrs

Any thoughts on what I should do differently - excluding running proper outdoor garden LV wiring...

 

 

 

[Cyknight]

70m on 22 gauge wire at 12v dc would see a drop of over 60% at 1A - so what you see isn't surprising. If you'd need to draw more, I doubt it could support 2 amps at that distance.

If possible, use 2 strands, that'll change the drop to 30% a 1 amp.

For a motion, you can simply use 3 wires (combine the positives, split at the device) and you could try using at least 2 conductors on the positive side of the LED feeds.

Failing that, you'll have to get a powersuply with adjustable voltage (ie built-in potentio meter) like a MeanWell A or AB LED powersupply. Even then, at that gauge, over those distances.....

You may need to use a 24v powersupply to get 12V over a single pair of 22 gauge conductors)at 2 amps....

https://www.calculator.net/voltage-drop-calculator.html

Don't just calculate and assume though, always measure before connecting your LEDs!

[lippavisual]

Yup voltage drop.  22 gauge= good for millivolt (ie: audio signals like mics) at long distances.  Power not so much.

Otherwise, always use 18 awg for power.  Can handle a couple hundred feet easily.

[brucecampbell]

Thanks for the info,  I might just try a 24V transformer and see what I get out the other side.

Failing that, I do have power out there, so could try using the existing cable to trigger a relay - however this might have the same issue - 6V might not be enough to trigger the relay switch...

Cheers.