Wire sizes

[its_me_jason]

just doing some wire research, thought I would share what i found with those who don't know yet.



--is it really important to use silicon wire?

--what type of wire are you using?

--Where do you get it?

--at what cost?

 

[ian.mich]

The insulation does not make much difference to performance, we usually try to run overkill gauges so we don't make use of the 200C insulation. Personally, i don't buy wire from anywhere but hobbyking.THeir wire is expensive as hell but it is industrial specced, super flexible, somewhat strong insulation, and their 10AWG can fit 4mm RC bullets. Plus, due to the thin-strandedness, the wire take no time to slide thru an axle, whether you use 14AWG (in silicone) or 12AWG (with silicone replaced with 3mm turnigy heatshrink).

 

[ddk]

your specs are leaving out the very important aspect of "wire length"

I use two 12 gauge in parallel, mainly for redundancy, because I'm fairly redundant.
Standard low voltage "zip" cord for landscape use. 42$ per 100'
I run 25A controllers where the longest length of power cable is 52" between battery and controller.
here's one of many "voltage drop calculators" found on the web so you can see when small, is too small.

 

[dogman dan]

Low voltage landscape lights cord can be a good choice. I scavenged some, but stopped using it because the insulation was sun cooked and nearly rigid. But inside was decent fine strand 12g wire, better than automotive grade stuff.

I've come to like the HK or EP buddy wire a lot though. The silicone insulation can cut easy though, so put some additional protection on it as it leaves battery boxes and such.

The wire sizes in the chart are for AC I bet. Where typically a run from panel to plug can be at least 40 feet. 3 feet long, we can get by with 12 or 10 guage on bicycles.

 

[wesnewell]

1--is it really important to use silicon wire?

2--what type of wire are you using?

3--Where do you get it?

4--at what cost?[/color]

1 no
2 copper
3 scrap wire in garage. Or one of a million places other wise
4 Nothing to so little not to worry about it.
For typical 30A controller system, any 14 awg or larger will work fine. Larger the better. 10awg will work fine to about an 80A controller system. 10awg never gets hot on my 40A system. Original battery wiring was 16 awg on 30A controller and it got warm, but not hot. As a test I used a 6" piece of 24awg wire in series with the regular wire, and while it got hot enough to melt the cheap insulation in a matter of minutes, it didn't fail. The smaller the wire, the more voltage drop you'll have, but for short runs it's really insignificant. Flexibility is a matter of choice. Wires from HK lipo are very flexible, so the rest don't need to be.
BTW, your charts are the sizes required for typical 120AC house circuits to meet code. Not their real amp capacity. You can double those values for ebike use of short runs easily. Still, larger is always better.

 

[bowlofsalad]

This might be a useful chart.

 

[ddk]

This might be a useful chart.

The chart is useful if one pays no attention to the "Watts" on this chart, unless one is running a 12V power system.

Wire gauge is all about current capacity and has nothing to do with Voltage*, but Voltage(x)current = the power-handling capacity of cable.

*Insulation material and thickness is what determines the maximum Voltage handling of cable, whereas silicon is such an overkill for an e-bike.
But silicon is very flexible... but only if the cable is too.

 

[its_me_jason]

Solid vs stranded wire!

what's your choice and why?

 

[marty]

Stranded wire for when it moves.
Sold wire for when it don't move.

For a electric vehicle - Stranded wire

 

[ddk]

Solid vs stranded wire!

what's your choice and why?

on an e-bike/trike/whatever, everything moves! Stranded wire should be your only choice. Where things flex more you should use more flexible wire (more strands)

The Justwin "cool e-trike" is an example of why one should never use solid wire- I've had to replace most it's accessory cabling with stranded wire.
The solid wire the factory used would fail at the connectors, because none of the wiring or connectors were supported... instead left to move about with every lil' bump. bump. bump.

 

[itchynackers]

This might be a useful chart.

*Insulation material and thickness is what determines the maximum Voltage handling of cable, whereas silicon is such an overkill for an e-bike.
But silicon is very flexible... but only if the cable is too.

I would think silicon insulation would be extremely stiff, since it is the same stuff used in microchips. I'd much rather have the flexible stuff used in ( o )( o ) implants, aka silicone, a totally different material (in spelling and pronunciation).

 

[its_me_jason]

Great posts guys! thanks

I especially enjoyed the voltage drop calculator. I had to scroll down a bit to find it, if anyone else want to see it. thanks ddk

 

[Kingfish]

• As a rule, I use this conservative chart by PowerStream for current capacity and for calculations.
• I like EP Buddy & TinnedMarineWire.com for hefty wire needs. I don't use HK because the domestic warehouse doesn't always carry what I need when I need it. Sometimes I use my Local Electronics Store when I've got to have it Now(); :lol:
• I use the noodley wire when it needs flexibility.
• Highest strands for flexibility, and AC conductivity.
• Solid wire is used only for Trace-Beefing, and I use 12- or 10-AWG.
• 12-AWG is the smallest I use, and that's for Phase Wiring through the Motor Axial.
• Battery interconnections and Phase Wiring from the Controller toward the Motor are 10-AWG.
• Pigtails to separate battery assemblies & to supply power to the Controllers are 8-AWG.
• The Main Battery Supply Bus is marine-grade 6-AWG and runs the length of my top-tube with a 6mm barrel connector for the trailer harness.
• All 8-AWG pigtails are swaged to the Main bus using Copper tubing.
• Every power connector is a barrel-type: 4mm for individual battery and for Phase Wires, 5mm for pigtails & controllers, and 6 mm for the Trailer & high-current charging tap.

Perhaps all the wire gauge & connections are overkill... although I no longer have lags
Cheers! KF

 

[Tommy L]

Gentlemen,

I believe something is being grossly overlooked.

Voltage voltage voltage. This higher the voltage, the more pressure there is, creating less resistance. Therefore, smaller wire and longer distances.
Examples:

120v DC 15amps #14 gauge wire 56 feet max (1800watts)
24v DC 15amps #14 gauge wire 11 feet max (360watts)
12v DC 15 amps #14 gauge wire 6 feet max (180watts)

Think of your car starter motor on 12v and the 1 to 4 gauge wire. Low volts needs big wire to do work without burning up. The current moves slower and becomes larger, hence, larger wire.

Electrical Pressure/Electromotive Force/Difference of Potential all mean Voltage.
The higher the voltage the greater the electrical pressure and more coulombs
can pass quicker the less heat that is generated in the wire.
Or something to that effect.

I might not have this explained exactly. Luke! DoctorBass! Jeremy! Where are you?
Trying my best ....

Tommy L sends....

 

[Punx0r]

The ability of a cable to handle current is irrespective of voltage - the cable heating is caused by I^2R losses.

The reason the chart stated different maximum cable lengths for different voltages is probably due to not exceeding some arbitrary voltage drop on the cable run?

 

[its_me_jason]

• As a rule, I use this conservative chart by PowerStream for current capacity and for calculations.
• I like EP Buddy & TinnedMarineWire.com for hefty wire needs. I don't use HK because the domestic warehouse doesn't always carry what I need when I need it. Sometimes I use my Local Electronics Store when I've got to have it Now(); :lol:
• I use the noodley wire when it needs flexibility.
• Highest strands for flexibility, and AC conductivity.
• Solid wire is used only for Trace-Beefing, and I use 12- or 10-AWG.
• 12-AWG is the smallest I use, and that's for Phase Wiring through the Motor Axial.
• Battery interconnections and Phase Wiring from the Controller toward the Motor are 10-AWG.
• Pigtails to separate battery assemblies & to supply power to the Controllers are 8-AWG.
• The Main Battery Supply Bus is marine-grade 6-AWG and runs the length of my top-tube with a 6mm barrel connector for the trailer harness.
• All 8-AWG pigtails are swaged to the Main bus using Copper tubing.
• Every power connector is a barrel-type: 4mm for individual battery and for Phase Wires, 5mm for pigtails & controllers, and 6 mm for the Trailer & high-current charging tap.

Perhaps all the wire gauge & connections are overkill... although I no longer have lags
Cheers! KF

That Tinned Marine Wire looks great for an ebike, its cheap too! Unfortunately if you live in Canada, as i do. They tack on an extra $20 for shipping.
I think I found the cheapest place for fellow Canadians to buy wire, (if I'm wrong let me know) that's Hobbyking they charge by total weight. They might even have a warehouse up here.

 

[ian.mich]

Hobbyking is far more expensive than other wires, they use extremely fine strands and 200C silicone. For that type of wire it is the cheapest, but it is still quite expensive. Canada does not have an HK warehouse.