View Full Version : wire to motor


dr voodoo 2
09-20-2008, 11:42 AM
Hey guys what guage wire are u running off speedo to motor can u run 14 to 16 guage in 4 cell 13.5 or is there proven loss any help would be appreciated trying to keep pod bind down thanks

hankster
09-21-2008, 10:33 AM
Smaller wire means more resistance in the majority of cases.

http://www.hobbytalk.com/bbs1/showthread.php?t=229297

davepull
09-21-2008, 08:00 PM
IMO 14g is fine

Crptracer
09-23-2008, 07:20 PM
What they said^^^^cant go wrong

Racer XXX
10-01-2008, 06:17 PM
Put 12 Gauge On And You Will See A Notable Difference Especially Towards The End Of The Run, Your Car Probably Seems A Little Flat From The Middle To The End Of The Run.

davepull
10-01-2008, 06:45 PM
Put 12 Gauge On And You Will See A Notable Difference Especially Towards The End Of The Run, Your Car Probably Seems A Little Flat From The Middle To The End Of The Run.


here we go again

CClay1282
10-01-2008, 07:34 PM
here we go again

lol, people just dont understand electronics.

Jamie Hanson
10-02-2008, 02:19 PM
Easy answer is "run as large as you can without binding up the suspension movement." If I could get away with 10awg I would.

Casperbase
10-02-2008, 02:54 PM
What gauge do you people think the circuits are inside that tiny little speed control you guys think you need the big fat wires for?? Think about that for a minute.....

dr voodoo 2
10-02-2008, 02:54 PM
Easy answer is "run as large as you can without binding up the suspension movement." If I could get away with 10awg I would.




SHHHHHHHHHH The brushless god is speaking :thumbsup: okay 3 coat hangers it is

brian0525
10-02-2008, 03:19 PM
What gauge do you people think the circuits are inside that tiny little speed control you guys think you need the big fat wires for?? Think about that for a minute.....


The speedo gives you the on-resistance of the ESC and then the wire adds to that number. So the wire makes the total on-resistance higher and depending on what wire and how long will give you the total on-resistance.

mr_meat68
10-03-2008, 08:27 PM
What gauge do you people think the circuits are inside that tiny little speed control you guys think you need the big fat wires for?? Think about that for a minute.....

how much electrical experience do you have?

CClay1282
10-04-2008, 08:19 PM
how much electrical experience do you have?

well dont be shy, cmon and give us your thought. i think the same way as casperbase. enlighten us.

mr_meat68
10-05-2008, 12:21 AM
answer this....

what type of metal and plating do they use on the circuit boards inside these speed controls? maybe, just maybe they conduct a little better than you think.

how many amps is 14, 12, and 10awg wire rated for?

just use the 12awg wire.

ta_man
10-05-2008, 04:38 PM
I think the point is, it doesn't matter what is inside the speed control - you can't (realistically) do anything about that. But you can change what happens outside the speed control and since resistances in series are always additive, anything you do to reduce the resistance between the speed control and the motor reduces overall total resistance.

CClay1282
10-05-2008, 08:21 PM
I think the point is, it doesn't matter what is inside the speed control - you can't (realistically) do anything about that. But you can change what happens outside the speed control and since resistances in series are always additive, anything you do to reduce the resistance between the speed control and the motor reduces overall total resistance.

The thing is: By how much are you raising or lowering the resistance? Enough to matter? Who knows. I have ran just as fast with 14g as i have with 12g. Doesnt mean its not lower resistance, just means that i didnt see a difference. Just my 2 cents. may not even be worth that much :)

samgkd
10-05-2008, 08:25 PM
Will putting a heat sink on your battery wires lower the resistance?
Will a shorter piece of 14ga have lower resistance than a longer piece of 12ga?
Will solder with a low % of silver have lower resistance than solder without silver?

It goes on and on and on and on and on ...............................................

CClay1282
10-05-2008, 11:31 PM
It goes on and on and on and on and on ...............................................

AMEN.

ta_man
10-06-2008, 12:10 AM
The thing is: By how much are you raising or lowering the resistance? Enough to matter? Who knows. I have ran just as fast with 14g as i have with 12g. Doesnt mean its not lower resistance, just means that i didnt see a difference. Just my 2 cents. may not even be worth that much :)

[with deference to PMSIMKINS]
Would you choose not to replace a gritty front bearing simply because you didn't know how much faster it would make your car?


Will putting a heat sink on your battery wires lower the resistance?
Will a shorter piece of 14ga have lower resistance than a longer piece of 12ga?
Will solder with a low % of silver have lower resistance than solder without silver?

To answer your questions:
No (speedo/battery wire doesn't get hot enough to change resistance),
Depends (on how much shorter: 1/4 the length of the 12, yes, 1/2 the length of the 12, no),
Depends (on the solder composition).

It goes on and on and on and on and on ...............................................
... and the guys that take care of every one of the items they know of fromt that infinite list are likely to be faster than the ones that don't. (The preceeding should not be interpreted as me claiming to be one of those guys - I am surely not.)

CClay1282
10-06-2008, 12:44 AM
ok, lets talk about this. Everyone knows the more strands in a given size of wire, the less resistance. So why is there no talk about this on here? A 1000 strand peice of 14 ga (just a number), could have less resistance than a 700 strand peice of 12g of the same length (again, just a number, dont take it as fact). So why is there no talk about what quality, strand number and wire compisition on here? That should be just as important as what size the wire is.

lets look as solder joints now. say a guy takes his perfectly good 14g wire out because you guys tell him to run the biggest he can. then he solders in good quality 12g with a horrible solder job. now he just messed up the whole point to putting in 12g wire in the first place. He would have been better off just running the 14g and living with the .0000001 of a second he COULD have gained.

CClay1282
10-06-2008, 12:48 AM
dont get me wrong, i have 12g in the speedos that matter, it is just my thought on the whole issue. Why is it such a big debate? a guy with a good setup and good driving can run just as fast with 14g over 12g. until someone actually shows me proof that 12g gained them a significant amount over 14g then thats how i will think.

CClay1282
10-06-2008, 12:51 AM
[with deference to PMSIMKINS]
Would you choose not to replace a gritty front bearing simply because you didn't know how much faster it would make your car?

I would replace it simply because bearings are not suppose to be gritty not because i think it will make my car faster. I know that everything works together, but i dont think the wire thing should be such a big debate.

davepull
10-06-2008, 07:51 AM
dont get me wrong, i have 12g in the speedos that matter, it is just my thought on the whole issue. Why is it such a big debate? a guy with a good setup and good driving can run just as fast with 14g over 12g. until someone actually shows me proof that 12g gained them a significant amount over 14g then thats how i will think.


ditto great post

ta_man
10-06-2008, 09:40 AM
ok, lets talk about this. Everyone knows the more strands in a given size of wire, the less resistance. So why is there no talk about this on here? A 1000 strand peice of 14 ga (just a number), could have less resistance than a 700 strand peice of 12g of the same length (again, just a number, dont take it as fact). So why is there no talk about what quality, strand number and wire compisition on here? That should be just as important as what size the wire is.

lets look as solder joints now. say a guy takes his perfectly good 14g wire out because you guys tell him to run the biggest he can. then he solders in good quality 12g with a horrible solder job. now he just messed up the whole point to putting in 12g wire in the first place. He would have been better off just running the 14g and living with the .0000001 of a second he COULD have gained.

a) Don't know why "everyone knows that" since it is not true with respect to DC currents or even low frequency AC. (For a brushless motor operating at 25,000 RPM the current in the motor wires changes direction at 1250 Hz.) For high frequency AC the "skin effect" comes into play. But we are not dealing with megahertz AC current in our motors and so the surface area (related to the number of strands) of the wire makes no difference. Even at 10,000 Hz, the skin depth in copper is .66MM, so the different between a 1000 strand wire and a 700 strand wire is less then differences in wind resistance caused by variations in air pressure in a room. You can find more on the "Skin Effect" here: http://en.wikipedia.org/wiki/Skin_effect

b) The fact that someone may do a poor job of soldering does not make 14Ga better than 12Ga. It makes a good solder joint better than a bad one. Those are two different things that should not be confused.

trailranger
10-06-2008, 04:07 PM
Crazy People....
Do you need to run 12ga over 14ga? Not really. Will it make a difference, Yes only if your car is working fast already. If you car is working fast, and changing a 0.010" shim is noticable then you will notice a change in gauge. A larger guage wire will not make your car faster, but it will help the car get to speed faster than a smaller wire. Some racers use 16ga for PUNCH control, pod flex or weight reduction and they are just as fast as everyone else.

. I install what I have or what I can make work but always starting with the largest gauge i have in my pit box. Sometimes 12ga is hard to fit in some cars. When I retsock my supplies of wire, I normally just go with 25Ft of Black 12ga and 5ft of Red

pmsimkins
10-06-2008, 04:35 PM
[with deference to PMSIMKINS]


Sweet I got a citation! :)

CClay1282
10-06-2008, 04:38 PM
a) Don't know why "everyone knows that" since it is not true with respect to DC currents or even low frequency AC. (For a brushless motor operating at 25,000 RPM the current in the motor wires changes direction at 1250 Hz.) For high frequency AC the "skin effect" comes into play. But we are not dealing with megahertz AC current in our motors and so the surface area (related to the number of strands) of the wire makes no difference. Even at 10,000 Hz, the skin depth in copper is .66MM, so the different between a 1000 strand wire and a 700 strand wire is less then differences in wind resistance caused by variations in air pressure in a room. You can find more on the "Skin Effect" here: http://en.wikipedia.org/wiki/Skin_effect

b) The fact that someone may do a poor job of soldering does not make 14Ga better than 12Ga. It makes a good solder joint better than a bad one. Those are two different things that should not be confused.

You certainly seem to know alot more than i do about electricity and motors, but my point is, it wont make as big of a difference as you (as in people who run 12ga) lead everyone to think.

Im done with this issue. I have spoken my peice and have gotten out brained (lol). I will continue running what i run (12g or 14g) and leave it at that.

That is my opinion. :)

pmsimkins
10-06-2008, 05:26 PM
Actually everyone knows exactly how much difference it makes. Google "wire resistance calculator" and you can figure out exactly the difference for your specific car.

Whether you think that difference is worth $5 and 20 minutes of time is your choice. There is no debate or worthwhile discussion on this topic because the facts are the facts.

hipsterdufus
10-06-2008, 05:30 PM
OMG who cares

put a bigger battery in it so goes faster

pmsimkins
10-06-2008, 05:37 PM
OMG who cares

put a bigger battery in it so goes faster

Apparently you since you read it and posted! LOL

The people posting aren't bashing stampedes in the backyard so a bigger battery isn't an option. :)

samgkd
10-06-2008, 05:46 PM
QUOTE """No (speedo/battery wire doesn't get hot enough to change resistance),""""


Better check your electrical theroy, any increase in temperature will increase resistance and any current flow through a conductor will produce heat. This is a fact not fiction.

trailranger
10-06-2008, 07:40 PM
If you are worried about Skin Effect, Run Monster Cable with Magnetic Flux Tube technology. They swear that it keeps the highs and the low freq signals matched.

The theory that with solid wire, the Bass frequency will travel unresistriced through the copper, but with the higher freq treble it can only travel on the outer edges of the copper as the skin effect dictates.
http://farm3.static.flickr.com/2028/2164699476_5843029115_b.jpg

This is a piece of wire I got from the Hoover Damn when they were replacing transmission lines.

It is 10 interlocking strands that form a hollow cable that reduces the transmission loss created by the Skin Effect. That piece of copper is over 50 years old and bigger diameter than a "D" Cell battery

pmsimkins
10-06-2008, 08:57 PM
Monster cable is the biggest ripoff company.

I snicker whenever I see "oxygen free copper". The power of marketing.