volt drop on elv LED wiring

Gunnspark · Jul 30, 2013

Hi. I'm new to LED wiring and am wondering how to work out volt drop when using 24 volt drivers and 2mm elv cable. The length of run is about 20 metres. I've read that the 4% stays the same as 230v but what would be the maximum length of cable that could be used?

Gunnspark · Jul 30, 2013

its vdc Marvo

Marvo · Jul 30, 2013

Okay, so you have a circuit with an LED lamp as the load but the circuit actually consists of three resistances in series. First you have the resistance of the positive wire, then the load resistance then the resistance of the negative wire.

You can find the voltdrop across any of these resistances if you know the current flowing in the circuit in Amps and the value of the resistance in Ohms. This brings us back to the first formula I gave you Vdrop = IR

[ElectriciansForums.net] volt drop on elv LED wiring

Marvo · Jul 30, 2013

So, if you can find the datasheet for the 2mm CSA wire you're using you can get the resistance per meter. Then, as Yellowvanman says the driver may be constant current output so you'll need to find the manufacturers datasheet for that as well to establish the output. Once you know the resistance of the wire and the current in the circuit it's easy to work out the voltdrop per meter of wiring.

Guitarist · Jul 30, 2013

You've done brilliantly to keep giving advice Marvo, after some of those comments.

Chris sparky · Jul 30, 2013

I'm sorry, but when you come on here asking for advice, and someone actually takes the time to give you a solution. If you dont get/understand what they're saying you shouldn't then talk to them like they are the idiot.

Fair play to you marvo.