Battery Busbars/Cables?

No other 4/0ers here? 

I only use  4/0 pure copper cable  from inverter to busbar .    Two different Powerjack cable arcing  got the cable insulation on fire .    Two other Powerjack cables  crimp  came loose  and  the inverter  will not run  when loaded  and shut down .  

That might be the cable size that I been trying to guess I have that I have yet got the right size lugs I need. I know its the size that I can stick my thumb into the lug it self.  All I know, is hat it can handle 600A 12v with no issue, just better make sure you connector at the battery terminal can handle it. I've litterly melted the led from pulling toooo much amps at 12v.  That is why the 6k 12v invert I got has two sets of battery connectors. lol.  I try running it with one set, with that cable and ran into that very issue. so had to put another set to keep from pulling so much amps from one terminal from a battery. used two batts terminals to spread the load. had 4 tractor group 31 batteries on the box truck.  with a 300a Alternator.

12 hours ago, kazetsukai said:

No other 4/0ers here? XD

Heck even 2AWG at the right lengths is fine for all but the most extreme operating conditions at 48V.

 

Meh, 4' of CU 2/0. Everything else is AL bus bars. My thermal doesn't show a significant temperature increase even at 300A.

I'd up to 4/0 or 250mcm for a GS12 though. No justification for it with the 6K.

7 hours ago, NotMario said:

Meh, 4' of CU 2/0. Everything else is AL bus bars. My thermal doesn't show a significant temperature increase even at 300A.

I'd up to 4/0 or 250mcm for a GS12 though. No justification for it with the 6K.

I keep hearing about bus bars, do you make them or what?  I've got some copper bars that I bought on amazon.  They about 18 inch long and a inch wide about two quarters thick.  I don't know how much amps they would be able to handle at 24v.

15 minutes ago, The Blind Wolf said:

I keep hearing about bus bars, do you make them or what?  I've got some copper bars that I bought on amazon.  They about 18 inch long and a inch wide about two quarters thick.  I don't know how much amps they would be able to handle at 24v.

I have a pair of 1000A bus bars from Blue Sea in my current setup. Lots of studs for expansion, didn't quite need it all.

People do make bus bars using drill presses and taps... using an online calculator the suggested current limit for yours (18 inches by 1 inch by 0.14 inch thick) is 106A. I would have guessed higher honestly. 

If you want to DIY some solid, future proof bus bars you'd probably be looking at 4 inches wide, close to half an inch thick, with studs drilled and tapped at regular intervals, as well as some solution to mount it to a surface.

1 hour ago, The Blind Wolf said:

I keep hearing about bus bars, do you make them or what?  I've got some copper bars that I bought on amazon.  They about 18 inch long and a inch wide about two quarters thick.  I don't know how much amps they would be able to handle at 24v.

Go to your neighborhood steel shop. They'll have "flat bar" in a number of metals and size configurations. You can buy a plastic spacer to make it look pretty, or just use a 2x4. AL is very inexpensive. Copper may be pretty cheap if they don't have to special order it - but even still it should be far cheaper than on Amazon.

I use a drill and tap to make holes that you can drive a standard hex bolt into to hold the terminals in place. I'm sure you have a drill, and you can buy a very nice tap and die set for <100$ on amazon if you don't have one already.

1 hour ago, kazetsukai said:

I have a pair of 1000A bus bars from Blue Sea in my current setup. Lots of studs for expansion, didn't quite need it all.

People do make bus bars using drill presses and taps... using an online calculator the suggested current limit for yours (18 inches by 1 inch by 0.14 inch thick) is 106A. I would have guessed higher honestly. 

If you want to DIY some solid, future proof bus bars you'd probably be looking at 4 inches wide, close to half an inch thick, with studs drilled and tapped at regular intervals, as well as some solution to mount it to a surface.

There is some insane size recommendation for bus bars. The numbers don't seem to match up with their cable counterparts.

I'd probably try and get 2x1 instead of 4x1/2. Or double-stack 2x1/2 - but much harder to tap layers than a single piece.

 I  keep hearing about bus bars, do you make them or what?

YES  I   use 2   ten foot  3/4 inch  copper  water pipe  for the negative  bus bar  equal  20 feet with  15  battery banks  connected .   The  positive  are  4/0  pure copper cables    and  2 inch   L  shape  angle steel  separated  FAR  from the  negative  bus bar .   

3 hours ago, NotMario said:

Go to your neighborhood steel shop. They'll have "flat bar" in a number of metals and size configurations. You can buy a plastic spacer to make it look pretty, or just use a 2x4. AL is very inexpensive. Copper may be pretty cheap if they don't have to special order it - but even still it should be far cheaper than on Amazon.

I use a drill and tap to make holes that you can drive a standard hex bolt into to hold the terminals in place. I'm sure you have a drill, and you can buy a very nice tap and die set for <100$ on amazon if you don't have one already.

There is some insane size recommendation for bus bars. The numbers don't seem to match up with their cable counterparts.

I'd probably try and get 2x1 instead of 4x1/2. Or double-stack 2x1/2 - but much harder to tap layers than a single piece.

 

Actually I have a drill pres, and a full tap and die set Craftsman.  So basicly, the bus bar isn't what is being used through out the whole setup, so you still use cable. It just seemed like folks where ditching the cables and useing pure bus bars.  Cause I use a bus bar that can handle 750A with a 600a ANL fuse built into it with 10m studs

I got some other bus bars claiming to be able to handle 300a, but seems to heat up when I'm only pulling 150A. so might just take these copper bars and triple stack them since I got like 10 of them and tap an   die them with 10m studs to fix that issue.

So basicly, the bus bar isn't what is being used through out the whole setup,

i  got tired of drilling holes thru  copper  pipe .   The home depot L shape steel  has holes  punched  already and easy to  bolt the fuse  and copper  cable  to the  battery ,    

I have bus bars on mine just between batteries 

The bars have much lower resistance than my cables making balancing much simpler 

5 hours ago, Steve said:

I have bus bars on mine just between batteries 

The bars have much lower resistance than my cables making balancing much simpler 

Yeah, i do this too. Then a single pair of wires 2 the system bus bars, and 2 wires to inverter and other peripherals.
Bus bars make a battery bank look very clean - plus the benefits of consistent resistance.

9 hours ago, The Blind Wolf said:

Actually I have a drill pres, and a full tap and die set Craftsman.  So basicly, the bus bar isn't what is being used through out the whole setup, so you still use cable. It just seemed like folks where ditching the cables and useing pure bus bars.  Cause I use a bus bar that can handle 750A with a 600a ANL fuse built into it with 10m studs

I got some other bus bars claiming to be able to handle 300a, but seems to heat up when I'm only pulling 150A. so might just take these copper bars and triple stack them since I got like 10 of them and tap an   die them with 10m studs to fix that issue.

I was saying in case you didn't. 🙂 Many people don't have tap-and-die sets, lol.

Yeah, it would be impractical for me to solely use bus bars. There needs to be some movement permitted. I have 2 pairs of bus bars. One on the battery bank, and one pair for the central DC bus that all the devices connect to. Peripherals are connected via cable.

The capacity differs based on your tolerance for temperature increase. I've come to mostly ignore what the engineers say and instead monitor with a thermal under load to determine if my conductors are adequate.

Interesting. I wonder what sq-inch the cross section of a 3/4"copper pipe is.

I thought about copper pipe but went with aluminum flat bar 

Interesting. I wonder what sq-inch the cross section of a 3/4"copper pipe is

I  flatten the  3/4 copper pipe to be 1/16 by 2 1/2 .   The chart show about 400 amps .   My 60vDC battery times 400 amps is   24000 warrs .  2/0 cable is about  400 amps . 4/0 cable is  over 500 amps .  My max surge so far is less than 20000 watts  with the 4 ton heat pump .