I don't have a SUMO bot. Wish I did to be more helpful.
You can try this link for copper wire info. Includes
gauges, lengths, amps, resistances, AWG tables,
conductivities, etc.

k4shf, · I don't have a unit right in front of me to determine the exact wire AWG, but a typical connector would be 20-22 AWG. · · · There is a formula to calculate current based on wire gage... · Circular Mils =·((92 ^ ((36-AWG)/39))*5)^2 Maximum Current Density = ( Circular Mils / Current Density Constant·) * Dv · To be conservative most people use·a 'Current Density Constant' value of 1Amp for every 700 Circular Mils, so for 20-22 AWG wire you are looking at a maximum current density·of about 1.5Amps to .9Amps · There is also a derating value based on the number of strands in the wire... · 2-5 strands Dv = .8 6-15 strands Dv = .7 16-30 strands Dv = .5

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔ Beau Schwabe
IC Layout Engineer
Parallax, Inc.

"Irony hides in the deception of your current view of the situation" - Me ....
In other words, do not believe what you are told and what you immediately perceive until you find out the absolute truth for yourself from all possible angles.

I guess what you are think about is power drain at a completely stalled motor.

1.5amps may not be enough in competition.

Instead of 20-22 AWG, try 12-14 AWG for about 15 AMPs. Then it will merely be the limits of your motor, motor control circuit, and batteries.

Of course you don't really have to go that big. But wire cross-section is directly limiting the current capacity regardless of voltage.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔ "Everything in the world is purchased by labour; and our passions are the only causes of labor." -- David·Hume (1711-76)········

···················· Tropically,····· G. Herzog [noparse][[/noparse]·黃鶴 ]·in Taiwan

Hwang Xian Shen, Puddleby-on-the-Marsh.
WTF? --- just may mean "Was That Funny?" , or maybe something else.

Yeah....what I've got is 2650 mah NiMH cells....in the standard cell holder, that's only 4.8 volts...not good for electronics or servos.
Adding in a cell. Cell holder has leades that are 26 awg, not easy to solder on larger wire (without metling plastic).
Looking at upgrading servos to higher torque....increasing friction of tires....assuming that stall current of servo increases....

## Comments

5 Commentssorted by Votes Date Added0Vote UpVote DownYou can try this link for copper wire info. Includes

gauges, lengths, amps, resistances, AWG tables,

conductivities, etc.

www.radiolocman.com/shem/shem-cache.html?di=18899

humanoido

0Vote UpVote Down·

I don't have a unit right in front of me to determine the exact wire AWG, but a typical connector would be 20-22 AWG.

·

·

·

There is a formula to calculate current based on wire gage...

·

Circular Mils =·((92 ^ ((36-AWG)/39))*5)^2

Maximum Current Density = ( Circular Mils / Current Density Constant·) * Dv

·

To be conservative most people use·a 'Current Density Constant' value of 1Amp for every 700 Circular Mils, so for 20-22 AWG wire you are looking at a maximum current density·of about 1.5Amps to .9Amps

·

There is also a derating value based on the number of strands in the wire...

·

2-5 strands Dv = .8

6-15 strands Dv = .7

16-30 strands Dv = .5

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔

Beau Schwabe

IC Layout Engineer

Parallax, Inc.

In other words, do not believe what you are told and what you immediately perceive until you find out the absolute truth for yourself from all possible angles.

www.Kit-Start.combschwabe@Kit-Start.comwww.BScircuitDesigns.comicbeau@bscircuitdesigns.com0Vote UpVote Down1.5amps may not be enough in competition.

Instead of 20-22 AWG, try 12-14 AWG for about 15 AMPs. Then it will merely be the limits of your motor, motor control circuit, and batteries.

Of course you don't really have to go that big. But wire cross-section is directly limiting the current capacity regardless of voltage.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔

"Everything in the world is purchased by labour; and our passions are the only causes of labor." -- David·Hume (1711-76)········

WTF? --- just may mean "Was That Funny?" , or maybe something else.

0Vote UpVote DownAdding in a cell. Cell holder has leades that are 26 awg, not easy to solder on larger wire (without metling plastic).

Looking at upgrading servos to higher torque....increasing friction of tires....assuming that stall current of servo increases....

Or am I all wet and without a clue?

Tim T.