LED wire question

rustyjames · 05/04/2012, 08:55 PM

From what I've read, when wiring LEDs the recommendation is 20 awg stranded. I have a bunch of old speaker wire, not Monster cable, just 16 or 18 gauge wire. Is this OK?

kcress · 05/04/2012, 11:43 PM

No the recommendation is 24AWG. 22AWG is OK too.

20AWG is getting too stiff. 16 or 18AWG is a bad idea.

Agua Salado · 05/05/2012, 10:55 AM

you are not going to be able to solder the thicker wires well. go spend $3 at radio shack or Harbor freight and get at least two different colors.

kcress · 05/05/2012, 01:34 PM

HAHAHA love your avatar Aqua!

Agua Salado · 05/05/2012, 03:23 PM

thanks

reefergeorge · 05/05/2012, 06:37 PM

I would just buy some cheap 22awg. with that said, I used 18awg on mine because I have spools of it. Its just a little harder to run clean.

TeslaReef · 05/08/2012, 03:59 PM

I've been wondering the same thing. I'm getting close to starting my led build with 750mA strings. Will the cat5 ethernet cable work? I believe it's 24 gauge.

Phillip

Mike31154 · 05/08/2012, 09:45 PM

It really depends on what type of LED you're wiring. Presumably you're talking the standard Cree 3 watt star in which case it would be difficult to solder the larger 16/18 gauge wire to the pad without cooking the LED. If you're using LEDs such as the 10 watt or larger multi chip emitters, larger gauge would be preferred since you're running a higher current. Smaller gauge wire adds resistance & heats up when too much current runs thru it. Look up the term 'ampacity' of wire. You should get some charts showing the maximum current allowable for a given gauge of wire. Compare this to the current required to run the LEDs of your choice & you should have your answer. Within reason, the larger the wire gauge, the better. Less resistive loss per foot & less chance of overheating.

tomservo · 05/08/2012, 10:54 PM

CAT5 cable strands will work, plenum rated is preferred because it will typically have a higher melt temp. CAT5 tends to not take solder very well in some cases. Keep in mind that 24ga wire is only good to about 2A for short distances (10 feet or so), so keep that in mind if you want to use it for the run to the driver. (At 10', there would be a 1V drop with a 2A load, you could get away with more than that but the wires will get warm/hot)

see here http://genuinedealz.com/voltage-drop.html

I have been using 18ga automotive wire rated 60v / 80C, it works quite well as it resists shrinking/melting when you tin it, but it gets pricey if you have to run all over to complete color strings.

I've been building 2 x 72 led fixtures for a friend lately and learned that serious forethought will save you big time... I ended up having 8 white / 4 blue per aluminum strip and to get the voltage I wanted to work at, I have 2 strings of 12 blue and 4 strings of 12 white, but to get those numbers I have to tie together 3 strips worth of blue etc. It sounds straightforward but it is a LOT more work than just sizing your power supply accordingly. I'm designing (and just about to order drivers for) a 198 emitter fixture and am being very careful to order the right drivers to save time.. In my case it means a HLG320-54 for whites (16 per row), HLG185-48 for blue(8 per row), LPF90-48(2 per row) for ocean coral and LPF60-15 for violet (3 per). Not only is it less work, it's more straightforward and I'll be less likely to screw things up. Plus it will be easier to troubleshoot if there is trouble. (total fixture wattage 598w)

I found some really nice 18g / 9 conductor wire for a good price on *bay, it is used for installing car stereo amps for 4 speakers. The outer jacket is black and thick, but the wire has good flexibility and 18ga is good to 7-8A with a low voltage drop.

Just to be clear, a voltage drop is wasted power.

edit: Just realized I hadn't answered the question I was going to - yes, speaker wire will work fine, but that low temp vinyl (PVC) jacket on speaker wire will turn to goo when it gets hot.

Landsailor · 05/09/2012, 05:11 PM

Quote:

Originally Posted by rustyjames

I have a bunch of old speaker wire, not Monster cable, just 16 or 18 gauge wire.

Good.

You should never under any circumstances buy Monster Cable.

Don't cheap out and "use what you have" because you think it will save a couple bucks. If you're not willing to buy the right wire, you're in the wrong hobby.

05/04/2012, 08:55 PM	#1
rustyjames EMT-B Join Date: Feb 2009 Location: Virginia Posts: 879	LED wire question From what I've read, when wiring LEDs the recommendation is 20 awg stranded. I have a bunch of old speaker wire, not Monster cable, just 16 or 18 gauge wire. Is this OK? __________________ I see your Schwartz is as big as mine. Current Tank Info: 20 long

05/05/2012, 06:37 PM	#6
reefergeorge Registered Member Join Date: Jun 2006 Location: St Louis MO Posts: 4,222	I would just buy some cheap 22awg. with that said, I used 18awg on mine because I have spools of it. Its just a little harder to run clean. __________________ $35-50 for a <1" frag of some stupid named thing that came from a colony you bought for $40-60 wholesale and chopped into 20-40 pieces? No thanks. "JasonH" Current Tank Info: 125 aggressive reef, DIY led lighting, swc cone skimmer, 33 gallon sump, posiden Ps3 return.

05/08/2012, 09:45 PM	#8
Mike31154 Registered Member Join Date: Apr 2008 Location: B.C. Canada Posts: 1,555	It really depends on what type of LED you're wiring. Presumably you're talking the standard Cree 3 watt star in which case it would be difficult to solder the larger 16/18 gauge wire to the pad without cooking the LED. If you're using LEDs such as the 10 watt or larger multi chip emitters, larger gauge would be preferred since you're running a higher current. Smaller gauge wire adds resistance & heats up when too much current runs thru it. Look up the term 'ampacity' of wire. You should get some charts showing the maximum current allowable for a given gauge of wire. Compare this to the current required to run the LEDs of your choice & you should have your answer. Within reason, the larger the wire gauge, the better. Less resistive loss per foot & less chance of overheating. __________________ Mike Current Tank Info: 77g sumpless sw with rock, sand, a few critters, fishes & polyps. Lights, pumps.....

05/08/2012, 10:54 PM	#9
tomservo Registered Member Join Date: Feb 2012 Location: Manitoba, Canada Posts: 332	CAT5 cable strands will work, plenum rated is preferred because it will typically have a higher melt temp. CAT5 tends to not take solder very well in some cases. Keep in mind that 24ga wire is only good to about 2A for short distances (10 feet or so), so keep that in mind if you want to use it for the run to the driver. (At 10', there would be a 1V drop with a 2A load, you could get away with more than that but the wires will get warm/hot) see here http://genuinedealz.com/voltage-drop.html I have been using 18ga automotive wire rated 60v / 80C, it works quite well as it resists shrinking/melting when you tin it, but it gets pricey if you have to run all over to complete color strings. I've been building 2 x 72 led fixtures for a friend lately and learned that serious forethought will save you big time... I ended up having 8 white / 4 blue per aluminum strip and to get the voltage I wanted to work at, I have 2 strings of 12 blue and 4 strings of 12 white, but to get those numbers I have to tie together 3 strips worth of blue etc. It sounds straightforward but it is a LOT more work than just sizing your power supply accordingly. I'm designing (and just about to order drivers for) a 198 emitter fixture and am being very careful to order the right drivers to save time.. In my case it means a HLG320-54 for whites (16 per row), HLG185-48 for blue(8 per row), LPF90-48(2 per row) for ocean coral and LPF60-15 for violet (3 per). Not only is it less work, it's more straightforward and I'll be less likely to screw things up. Plus it will be easier to troubleshoot if there is trouble. (total fixture wattage 598w) I found some really nice 18g / 9 conductor wire for a good price on bay, it is used for installing car stereo amps for 4 speakers. The outer jacket is black and thick, but the wire has good flexibility and 18ga is good to 7-8A with a low voltage drop. Just to be clear, a voltage drop is wasted power. edit: Just realized I hadn't answered the question I was going to - yes, speaker wire will work fine, but that low temp vinyl (PVC) jacket on speaker wire will turn to goo when it gets hot. Last edited by tomservo; 05/08/2012 at 11:14 PM.*

05/04/2012, 11:43 PM	#2
kcress Registered Member Join Date: Dec 2007 Location: Central California Coast. Posts: 5,383	No the recommendation is 24AWG. 22AWG is OK too. 20AWG is getting too stiff. 16 or 18AWG is a bad idea.

05/05/2012, 10:55 AM	#3
Agua Salado Moved On Join Date: Jul 2011 Location: Tampa Posts: 330	you are not going to be able to solder the thicker wires well. go spend $3 at radio shack or Harbor freight and get at least two different colors.

05/05/2012, 01:34 PM	#4
kcress Registered Member Join Date: Dec 2007 Location: Central California Coast. Posts: 5,383	HAHAHA love your avatar Aqua!

05/05/2012, 03:23 PM	#5
Agua Salado Moved On Join Date: Jul 2011 Location: Tampa Posts: 330	thanks

05/08/2012, 03:59 PM	#7
TeslaReef Registered Member Join Date: Mar 2012 Posts: 64	I've been wondering the same thing. I'm getting close to starting my led build with 750mA strings. Will the cat5 ethernet cable work? I believe it's 24 gauge. Phillip