dune16
Active member
Tried using wire size calculators but getting mixed answers. I have a dc jack on awg20 cable. I want to use this on my TV. Power will be 19v 2.1a. Cable run is only about 1.5m. Will this wire size be OK?
Thanks
Thanks
Wire size question
- Thread starter dune16
- Start date
PaulRainbow
Well-known member
We don't use awg in the UK, we use csa (mmsq). For robustness you should not use anything thinner than 1.0mm for power circuits, this will be fine for your TV socket.
Last edited:
andsarkit
Well-known member
Yes OK.
This calculator is suitable for boat calculations 12 volt planet
I'm more used to metric measurements where 0.5mm2 = 20awg
Some calculators use the one way measurement and double it for the total length while others want you to input the total wire length.
A 2v drop in a mains system is insignificant but would be serious on a 12v system
This calculator is suitable for boat calculations 12 volt planet
I'm more used to metric measurements where 0.5mm2 = 20awg
Some calculators use the one way measurement and double it for the total length while others want you to input the total wire length.
A 2v drop in a mains system is insignificant but would be serious on a 12v system
PaulRainbow
Well-known member
In general, i would not waste time with wire size calculators for boat wiring. I'd start with 1.5mm wire and use it for everything it was suitable for, then use 2.5mm wire for everything between 1.5mm and 2.5mm. Above that, it's 4mm, 6mm, 8mm, 10mm, 16mm, 25mm, 35mm. 50mm..........
Keeps it nice and simple, no need to have a million different wire sizes. It also means you need a minimal selection of terminal sizes and tooling.
The voltage drop calculator linked to in post #3 is fine to use, just feed in the data and set the wire size to 1.5mm, if the voltage drop is 3-4% or less, you're good to go, else try 2.5mm etc etc. Pretty much everything except heavy loads will be fine with 1.5mm or 2.5mm
Keeps it nice and simple, no need to have a million different wire sizes. It also means you need a minimal selection of terminal sizes and tooling.
The voltage drop calculator linked to in post #3 is fine to use, just feed in the data and set the wire size to 1.5mm, if the voltage drop is 3-4% or less, you're good to go, else try 2.5mm etc etc. Pretty much everything except heavy loads will be fine with 1.5mm or 2.5mm
dune16
Active member
Yes, I have a load of 2 core 1.5mm2 and 2.5mm2 oceanflex for previous jobs, just the lead for the TV is already made up and I was trying to keep it simple....but didn't want to risk if it was undersized. I'll use it for the tv though on your advice ?
PaulRainbow
Well-known member
Looking back at this, are you talking about wiring within the boat for a TV socket, or a ready made lead to connect from a socket to the TV ?
If it's boat wiring, see above. If it's a lead to the TV you could use what you have, but fit a 3 or 4 amp fuse
dune16
Active member
Yes. Its just a lead coming from my dc 12v to 19v step up to the TV. Will be fused. Still OK to proceed? ?
PaulRainbow
Well-known member
Apologies, i misread your original post. Yes, OK to use that lead, i'd fuse it close to the converter to be safe.
ylop
Well-known member
The electrons don’t care where they are in the world! And in an increasingly global world it’s very easy to buy wire that is specified in awg! I agree with your approach of having sensible wiring that fits most purposes on board but knowing when that is a bad idea or if an existing wire is sensible still means I revert to wire size calculators from time to time.
superheat6k
Well-known member
So as most simply do not understand AWG or SWG
American Wire Gauge and Standard Wire Gauge are pretty much the same thing.
So what does it mean ?
So strip off the inner conductor and then wind it around a mandrel with each turn closely touching the next turn. How many turns measure one inch - that's it !
So 16 AWG means 16 turns next to each other measure one inch.
Importantly the lower the number the thicker the wire.
So you can see why using metric CSA (cross sectional area) using mm2 is far simpler.
So for the commonest metric sizes ...
CSA AWG
0.25mm2 24AWG
0.50mm2 20 AWG
0.75mm2 19AWG
1mm2 18AWG
1.5mm2 16AWG
2.5mm2 14AWG
4mm2 12AWG
6mm2 10AWG
10mm2 8AWG
16mm2 6AWG
25mm2 4AWG
Hopefully someone will find this useful.
American Wire Gauge and Standard Wire Gauge are pretty much the same thing.
So what does it mean ?
So strip off the inner conductor and then wind it around a mandrel with each turn closely touching the next turn. How many turns measure one inch - that's it !
So 16 AWG means 16 turns next to each other measure one inch.
Importantly the lower the number the thicker the wire.
So you can see why using metric CSA (cross sectional area) using mm2 is far simpler.
So for the commonest metric sizes ...
CSA AWG
0.25mm2 24AWG
0.50mm2 20 AWG
0.75mm2 19AWG
1mm2 18AWG
1.5mm2 16AWG
2.5mm2 14AWG
4mm2 12AWG
6mm2 10AWG
10mm2 8AWG
16mm2 6AWG
25mm2 4AWG
Hopefully someone will find this useful.
lustyd
Well-known member
We don’t use inches either ?
ylop
Well-known member
however it’s also not that intuitive! Looking at a wire and knowing it’s cross sectional area is not really obvious either. I can look at a wire and estimate whether it is 0.5mm, 1mm, 2mm or 4mm diameter easily but it’s far less intuitive to estimate areas of circles.
Alex_Blackwood
Well-known member
We used to use 3/029, 7/036 etc. had to get used to mm. What ever unit you are used to will be the easiest.
