Non-Copper Ampacity
Non-Copper Ampacity
(OP)
O.K. I've been all over Hell's creation on the web looking for a straight forward equation for this, but either I'm inept or impatient (I could also be both if you ask my wife...)
I am trying to determine the ampacity of a titanium current collector. I know the ballpark for copper is ~2A/mm^2, and there is a plethora of other info out there for copper and aluminum conductors. I just can't find anything for other metals.
The electrical conductivity of Ti (.0234) is about 1/30th that of Cu (.596). Something doesn't feel right about just doing a ratio to compare the two.
So, can someone lead me down the path to enlightenment. I'm looking for some equations or general "rules-of-thumb" for this type of calculation.
I am trying to determine the ampacity of a titanium current collector. I know the ballpark for copper is ~2A/mm^2, and there is a plethora of other info out there for copper and aluminum conductors. I just can't find anything for other metals.
The electrical conductivity of Ti (.0234) is about 1/30th that of Cu (.596). Something doesn't feel right about just doing a ratio to compare the two.
So, can someone lead me down the path to enlightenment. I'm looking for some equations or general "rules-of-thumb" for this type of calculation.






RE: Non-Copper Ampacity
The ampacity of a copper or aluminum conductor is directly related to whether or not it is a bare conductor, ambient air temperature and how it is installed. The ampacity tables are a combination of the physical properties, thermodynamics and practical experience. It won't be quite a simple when dealing with a non-standard conductors. But the heat generated is directly related to the resistance, so that can be calculated. The rest is not so simple.
RE: Non-Copper Ampacity
RE: Non-Copper Ampacity
RE: Non-Copper Ampacity
I'm just looking for some equations that I can plug the specs for my material into and churn out an approximate current that I can pump through the bar before it destroys my system. I'm just not finding them for anything except copper.
Clyde, it looks like that spreadsheet is for copper only. Am I reading it wrong?
Dan
www.eltronresearch.com
RE: Non-Copper Ampacity
RE: Non-Copper Ampacity
1. First calculate the resistance based in your geometry and the resistivity of the conductor material.
2. Then you can determine the power you're dumping in based on the resistance and the square of the current.
3. Then you can determine the heat added from the mass, specific heat of the material, and delta T. This will give you an output of Joules, and you've already got power (watts=J/s).
4. This will let you calculate the time it takes to to raise the temp by delta T.
5. If I do the heat-added calc on my coolant and set the two equal, I should be able to get in the ballpark of an equilibrium temp with some fudging here and there.
I just don't know why there isn't more info available on other metals besides the two big hitters. Anyway, I think I got the info that I needed. Thanks for the input, guys.
Dan
www.eltronresearch.com