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Conductor Current Ratings [SRO]

I’d like to make an easy-to-find list of current ratings for esk8 use.

If anyone has edits, corrections, experience, or thinks it can be better, please describe what you think should be changed. :smiley:

Popular esk8 sizes in bold.

This chart is labeled for continuous and not instantaneous. You can pretty much double every number for instantaneous, for a couple seconds or less.


Thanks @sebaszz

Thanks Lund Instrument Engineering



Maybe include voltage/power loss? :thinking:

Length of all materials is “less than one meter, for esk8 use” :smile:

So, the length of a longboard maximum. Obviously, shorter is better.


I was thinking detailed ratings like that are available but I wanted a condensed, easy-to-use, especially for n00bs format.

This is specifically-as-relating-to-esk8 only and not intended for other uses.

There is a calculator for all that if you follow the Lund Instrument Engineering link above

Shooting from the hip, I would limit that to 30A continuous, 55A peak.

I would strongly recommend silicone-insulated fine-stranded copper wire for that. It will hold up to vibrations much better.

Might as well add common connectors. Jst xh/ph, bullet, xt, dc barrel, etc.


Never mind the extremely informative and concise post, what I want to know is why the double zero in noobs. Is it because noobs looks a bit like boobs if you use 2 o’s

Brian you old perv


You sir, are a Gentleman and a Scholar.


That chart for nickel strip is a bit underated just as every other chart is, one strip of 0.15 x 10mm pure Nickel can handle a lot more than 6.71 amps without heating up.


If you follow the Lund link in the second post, there is one :smirk:

This chart is labeled for continuous and not instantaneous. You can pretty much double every number for instantaneous, for a couple seconds or less.

I added this to the first post.

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Good thread. One thing i would like to know is the amount of current going through motor phase wires.

Lets say your motor max is 90a but you have 3 phase wires. is it a simple 30a per wire? or does it cycle 90a per wire very quickly?

It’s 3 phase AC so it cycles between all three in a rotation. Each one is probably “on” for two-thirds of the time.

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When building a battery, am I correct in assuming that these ratings only matter for the series connections as the p connections are only for balance?

This is 0.15 x 12mm nickel, so with 13 x series connections at say 8a per connection I should be good for 104a continuous… would like it to comfortably be 200… am I better to solder some wires across or double up all the s connection nickel?

And then for battery pos and neg, it should be fine to just run multiple copper wires to BMS to allow for 200a?


Do you want a 200A continuous battery? What do you want?

I want it to be capable of 200a continuous. I understand that it will never reach that, but this is a dick swinging activity.


Five 12AWG wires for each series connection (spread evenly along the nickel) would deliver that. And on the B+ and B-, five 12AWG coming from the nickel and then combined into a single 0AWG would make for a 200A continuous connection that would run cool.

Complete overkill for any esk8. But it’s what you need for 200A continuous, 400A peak


You would need a wire of this size

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Could I just run multiple wires to the BMS rather than connecting to a single monster wire :sweat_smile: i have 8awg on hand so I could use 3 of them for 210a?

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Yes :slight_smile: