Jehu PCB XT60 vs Brass Standoff

chris669

New member
Joined
Nov 7, 2018
Messages
10
hi, just received it. One point I do not understand with this bcb, the current can go through the xt60, that's ok, and also via the brass standoff, is this just to be able to provide the necessary Amperage? Thanks, Chris
 
chris669 said:
hi, just received it. One point I do not understand with this bcb, the current can go through the xt60, that's ok, and also via the brass standoff, is this just to be able to provide the necessary Amperage? Thanks, Chris

Some users have tested the brass standoffs and found the resistance they have is negligible, and shouldn't have any issue with high current (I would still limit the PCB stacks to 10 boards or less). Initially based on some calculations of wire gauge/ampacity vs. the brass standoff cross sectional areaI thought the XT-60s would be needed to carry extra current, but the limiting factor was the cell holders (4A max), so it was not an issue. The XT-60 can still be used as a "top of stack" connector for pulling power from, if you don't want to use a screw terminal.
 
In fact, knowing how thick and short the brass connections are, I would first worry about the XT60 connectors burning out before the brass standoffs do :)

Well, if you are running 10+ of these :D
 
rev0 said:
chris669 said:
hi, just received it. One point I do not understand with this bcb, the current can go through the xt60, that's ok, and also via the brass standoff, is this just to be able to provide the necessary Amperage? Thanks, Chris

Some users have tested the brass standoffs and found the resistance they have is negligible, and shouldn't have any issue with high current (I would still limit the PCB stacks to 10 boards or less). Initially based on some calculations of wire gauge/ampacity vs. the brass standoff cross sectional areaI thought the XT-60s would be needed to carry extra current, but the limiting factor was the cell holders (4A max), so it was not an issue. The XT-60 can still be used as a "top of stack" connector for pulling power from, if you don't want to use a screw terminal.
Ok, I've seen now on the board they mention Aluminum 8mm hex M4 for 20 modules in stack. But If I dirty compare to AWG1 7.34mm is 119A, I could easy go to 30 modules (3A per board) , assuming the fact I will never exceed C1 for these cells and my inverter has a transfo that will not exceed 3000VA (230VAC for off grid household) and max power would be used for a duration of 10 minutes max. Please do not hesitate to correct me!

Now I'm lost, I can read aluminum has better electric conductivity than copper and in some other places copper has better conductivity, what's right?

image_mdzrzx.jpg


image_nyylkx.jpg
 
chris669g power from said:
Now I'm lost, I can read aluminum has better electric conductivity than copper and in some other places copper has better conductivity, what's right?

image_mdzrzx.jpg


image_nyylkx.jpg

Im getting 14s2p boards that Im planing to instead of stack vertical... im planing to go horizantal , in this way weight aint an issue...in terms of amp capatity...
My max load is 20 to 25amp....So the number of boards can be large since the current is not that high
Thanks!
 
Brass is not copper. Brass is an alloy of copper and zinc and has a much lower conductivity than copper or aluminum. You will need 3x or more brass to be equivalent to copper or aluminum. Brass is not as soft than pure copper, which is why it is used.

Copper has better conductivity than aluminum but more expensive per pound.
 
not2bme said:
Brass is not copper. Brass is an alloy of copper and zinc and has a much lower conductivity than copper or aluminum. You will need 3x or more brass to be equivalent to copper or aluminum. Brass is not as soft than pure copper, which is why it is used.

Copper has better conductivity than aluminum but more expensive per pound.

Now china is selling this standoff as StanilessSteel instaed of Brass.Brass or StanilessSteel ?

CG
 
+ 1 copper is a better conductor that aluminium.
Brass is still a very good conductor.
As long as you have enough of it the exact conductivity is irrelevant.
Like said already, brass can be machined better than copper.
Buy brass. Electrical wholesalers sell brass busbars not aluminium.
One reason to use brass is aluminium develops an insulating oxide layer with air. Ie it'll be fine at first, then later develop hot spots/bad joints.
 
Back
Top