Would this 18 AWG 0.75mm Cable be ok for series wiring

[Joe34]

http://www.ebay.co.uk/itm/331628650632

Cable Specs

Conductors – Tin Coated Pure copper
Strands – 24
Strand thickness – 0.2mm
CSA – 0.75mm (squared)
Min. insulation resistance 20°C (MΩ/km)- 10
Rated conductor temperature- 85°C
Rated to 4.5A & 1000VUnshielded & Single Core

Price seems to good to be true

I was planning to use the above for 5x 1212's at 1450mA 36v each.

Most people recommend 18 AWG, but I noticed the strand quanitity and strand thickness are not all the same for all 18 AWG rated cables...

Some 18 AWG is 1mm thick, some 0.75mm thick..., the Amperage difference in this 0.25mm difference is quite large.

 

[Joe34]

Could it be the case that this "18 awg" is not actually 18? maybe 19-20 AWG...

 

[CobKits]

use solid wire it works a lot better in holders. esp large diameter stuff like that. 18 ga wire is 1mm diameter and is at the limit of spec for many holders like bjb that are technically rated to 0.75mm diameter. it works where stranded may not

the 0.75mm^2 youre seeing in that spec is the cross sectional area

3.14159 * (0.5)^2 = 0.78mm^2

 

[Joe34]

@CobKits I will no longer be using BJB, they are too expensive. Instead I will solder direct to COB.

What can you recommend for that?

 

[CobKits]

18 solid has more than enough current capacity and is easy to work with. i dont like stranded wire for most applications, all of the commercial wiring ive done is solid as well

 

[greg nr]

One caveat to all of this is that if the wire is going to flex, DON'T use solid wire. If you are securing it in a chase or along a channel, it s fine. But if you are going to run it like an extension cord to a remotely mounted driver, don't use it.

Just take a piece of solid wire and bend it back and forth a few times; it will break quickly. That won't happen with stranded wire.

 

[CobKits]

But if you are going to run it like an extension cord to a remotely mounted driver, don't use it.

if youre gonna do this over any decent length you should step up to 12 or 14 GA anyway. cheaper to cut up extension cords in many cases. and yes theyre all stranded

 

[Joe34]

if youre gonna do this over any decent length you should step up to 12 or 14 GA anyway. cheaper to cut up extension cords in many cases. and yes theyre all stranded

so it wud be better to use normal 18 awg for all cobs after the first one, but 12-14 awg for the last cob and first cob to the driver(if mounting driver far away) - for cost efficiency?

 

[CobKits]

well 12GA wire costs more than thinner wire but will be slightly more efficient. dont over think the last $5 of your several hundred dollar project