# LED Drivers on Lighting Circuit

Discussion in 'Electricians' Talk' started by bourlon, Jan 14, 2020.

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1. ### bourlonNew Member

Got some led's and drivers for the kitchen, for each driver there will be 2 rolls of tape, 72 watts each, a total of 3 amps, and there will be 2 drivers in the kitchen circuit.

This seems a bit close. I would appreciate the readers thoughts.

2. ### Bob RathboneWell-Known Member

Firstly, when using the LED on a roll system, you need to be aware that the sticky tape is useless. It will slowly come unstuck, so use an additional fixing such as staples carefully placed over the strip with a piece of insulating material between. I agree that the rating is close, but as it does not exceed the PSU output, it should be OK.

3. ### Mike58Active Member

144W of LED lights - have you checked to see how bright that will be? That is probably in excess of 1kW incandescant equivalent.

4. ### bourlonNew Member

These we specified by a specialist LED supplier, they will be on a dimmer - now need to check the capacity of the dimmer!!

6. ### bourlonNew Member

I spoke with the supplier's tech dept. The input power is only 1/10 th of the output.

Thanks everybody

7. ### Mike58Active Member

Absolute RUBBISH ... how can the ouput power be 10x greater than input unless they have discovered "free energy".

8. ### EneyNew Member

I agree, will put a camp meter on see what the true value is.

9. ### BazzaWell-Known Member

Maybe they said current , not power?

10. ### Hans_25Well-Known Member

Power in = power out. Energy can neither be created nor destroyed.

11. ### MGWWell-Known Member

You say 72 watt each and total 3 amp so that means 12 volt so the input current is only 1/20 th of the output. So even if they said current not power, there is something wrong?

12. ### EneyNew Member

they are 24 volts

13. ### BazzaWell-Known Member

Yes, in a transformer power in = power out

But the current will change in an inverse ratio to the voltage change.
Your transformer has a voltage change ratio of 10:1, so the current will be 10 times higher on the 24v side than the 240v side.
You misheard, or misunderstood what you were told.

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14. ### Mike58Active Member

Yes, but not always as "electrical power" some will be lost as heat and maybe sound.

15. ### BazzaWell-Known Member

Was hoping to avoid having to go through the minutiae of transformer losses in what (should be) a simple matter.

Last edited: Jan 18, 2020 at 11:16 AM
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16. ### Hans_25Well-Known Member

240 volts at 1 amp = 240 watts

At 24v volts for the same power, current will be 10 amps. At 12 volts for the same power current will be 20 amps. That's why I bought 24v LED strips not 12V

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