All busbar s not created equal

Stepandwolf

Solar Addict
I'm going to install the Blue Sea's I ordered, but here is the link to the one I've been talking about.


This R2X Racing is not copper; its nickel coated brass.
Those are what I ordered for my build. Haven't wired things yet so I don't know if I will have a problem.
 

CopperBusbar

New Member
The listing for that bus bar is kind of goofy. The measurements of 25" x 2" x 10" caught my eye. What they meant was .25" x 2" x 10".

Further down, they list it as rated for 710 amps. AC or DC? Does it matter? Serious question. It's non-mechanical, unlike a circuit breaker, so I'm not sure that AC or DC matters. At some point, voltage would seem to matter, but I don't have any idea on that.

Are the brackets really stainless steel? They look like galvanized steel to me.
Brackets are stainless.
 

Texas-Mark

Solar Addict
Why would anybody build a bussbar from brass? Tinned copper much better… at 300A the brass one likely heats up…

I have been looking for some busbars to neaten up my cables. Currently I have 5 lugs just stacked on a bolt. Works fine, no heat, just looks sloppy. I was looking for some busbars with studs and it seems all of the "affordable" ones are nickle plated brass. The copper ones are like $80 a piece for 4 studs. I need 2. I have a hard time justifying $160 over a couple of 50 cent bolts that work fine.

So my question is, just how much of a difference do the plated brass ones make in real life (not theoretical)? My max current will only be around 100 amps. I see a lot of pictures posted here of busbars with studs and I doubt most of them are copper.
 
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chrisski

Photon Sorcerer
So my question is, just how much of a difference do the plated brass ones make in real life (not theoretical)? My max current will only be around 100 amps. I see a lot of pictures posted here of busbars with studs and I doubt most of them are copper
I don’t know. If I get a 250 amp busbar, I expect it to do 250 amps for hours on end even if I will never reach that, not a max surge of 250 amps for a few minutes. Since everyone’s power requirements are a bit different, a test based off how it held up in a system is not that controlled.

Those nickel plated Brass busbars that get put in cars don’t get used like in a solar build where induction cooktops or air conditioning systems are used. It’s not just a stereo system hooked up to a 250 amp amplifier.

What I would like to do is find a chart that lists how much a brass busbar is rated for and see if the brass busbar that comes with the system meets a 250 amp rating, or even a 100 amp rating.

I’m sure the 250 amp busbar in this thread will hold up to most uses, but to me the NEC code has been written off of 120 years of electric accidents and still we have 300k+ electric fires a year. Most builds on this forum fall outside the NEC code, or any code at all, so are basically unregulated. THere’s the occasional fire. That’s what I’m trying to prevent for my RV.
 

Hedges

I See Electromagnetic Fields!
I have been looking for some busbars to neaten up my cables. Currently I have 5 lugs just stacked on a bolt. Works fine, no heat, just looks sloppy. I was looking for some busbars with studs and it seems all of the "affordable" ones are nickle plated brass. The copper ones are like $80 a piece for 4 studs. I need 2. I have a hard time justifying $160 over a couple of 50 cent bolts that work fine.

So my question is, just how much of a difference do the plated brass ones make in real life (not theoretical)? My max current will only be around 100 amps. I see a lot of pictures posted here of busbars with studs and I doubt most of them are copper.

You can DIY busbars with a copper bar and insulated standoffs.
McMaster-Carr has them. On-Line Metals is cheaper.



If you have two batteries and one inverter or vice versa, you can place wires in an order so busbar carries half as much current through any part of its cross-section. You can also put two cables on opposite sides of the busbar. I have one battery on center bolt, four inverters on outer two bolts.


Look up resistivity of your brass alloy, and considering cross-section, compare it to copper wire ampacity and IR drop. You want IR drop of busbar to be negligible compared to cable, and if ampacity (scaled for busbar from single free wire tables) isn't exceeded, you'll have an idea of max temperature.
 

Texas-Mark

Solar Addict
You can DIY busbars with a copper bar and insulated standoffs.

Yeah, I thought about doing that. Just wanted something that looked nice. I did not expect them to be so expensive for what it is.
I was just curious about real wold use of the plated ones. I don't recall ever reading anyone complaining that that their plated brass bus bars were overheating.
 

Q-Dog

¯\_(ツ)_/¯
I have been looking for some busbars to neaten up my cables. Currently I have 5 lugs just stacked on a bolt. Works fine, no heat, just looks sloppy. I was looking for some busbars with studs and it seems all of the "affordable" ones are nickle plated brass. The copper ones are like $80 a piece for 4 studs. I need 2. I have a hard time justifying $160 over a couple of 50 cent bolts that work fine.

So my question is, just how much of a difference do the plated brass ones make in real life (not theoretical)? My max current will only be around 100 amps. I see a lot of pictures posted here of busbars with studs and I doubt most of them are copper.
Just get the Blue Sea Maxibus ... 250 amps, tinned copper, $30 plus shipping.
 
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Texas-Mark

Solar Addict
250 amps, tinned copper, $30 plus shipping.
Blue Sea Systems 2127 Maxibus BusBar 250 Amps

Not in stock, and I question whether it is a knock off (not copper) at that price.

On Walmart I see these. Same picture and descriptions. The first one "appears" to be a knock off though, as it does not list a mfg under the details.

$33
and
$53
 

chrisski

Photon Sorcerer
The insulators were what I was looking for. A couple more questions. Seems like you’ve done this before.

Now, how do you cover these. I can only come up with some homemade cut ABS plastic. Pretty sloppy.

Second, how do you secure the studs? Of course I could drill and use a bolt and nut, but I’m sure that’s best. 1/4 inch may not be enough to drill and tap.
 

Q-Dog

¯\_(ツ)_/¯
Not in stock, and I question whether it is a knock off (not copper) at that price.

On Walmart I see these. Same picture and descriptions. The first one "appears" to be a knock off though, as it does not list a mfg under the details.

$33
and
$53
I have this one installed in my setup ... the link I posted is the exact one I bought. It is exactly what it says it is. I would trust PKYS before I would trust WalMart for solar/boat electrical gear. ;) Call them and ask when they expect more.
 

smoothJoey

SmooJo
The insulators were what I was looking for. A couple more questions. Seems like you’ve done this before.

Now, how do you cover these. I can only come up with some homemade cut ABS plastic. Pretty sloppy.

Second, how do you secure the studs? Of course I could drill and use a bolt and nut, but I’m sure that’s best. 1/4 inch may not be enough to drill and tap.
Does it really need to be covered?
 

chrisski

Photon Sorcerer
Does it really need to be covered?
Its in an RV pass through storage, so I would say yes it needs to be covered. Very tight Installation. WHen I work on things, I don’t want a tool inadvertently dropped or something comes off years down the road and bounces through the compartment when driving. I’ve got the RV at the shop as they repair the damage to a tire blow out. I also got to think of making it safe for things like that.

Really don’t need a covered busbar, but a way to isolate it. I do have Kapton tape, at least I think its called that, the transparent orange tan tape that can provide a little installation.

I’ve built some busbar s before, but that was for terminals and drilled the copper for it.
 

smoothJoey

SmooJo
Really don’t need a covered busbar, but a way to isolate it. I do have Kapton tape, at least I think its called that, the transparent orange tan tape that can provide a little installation.
That is a accurate description of Kapton tape.
Mine is covered but, for future builds I might leave it uncovered.
If every positive wire is over-current protected and something makes contact with the negative busbar, the fault will cleared.
 
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Hedges

I See Electromagnetic Fields!
The insulators were what I was looking for. A couple more questions. Seems like you’ve done this before.

Now, how do you cover these. I can only come up with some homemade cut ABS plastic. Pretty sloppy.

Second, how do you secure the studs? Of course I could drill and use a bolt and nut, but I’m sure that’s best. 1/4 inch may not be enough to drill and tap.

I had bought something like this ready-made from an eBay vendor, but same idea. Besides drilled copper bar and insulators, it had aluminum brackets to go between insulators and mounting surface.
Thru-holes with bolts and nuts to hold ring terminals. That lets me do top and bottom wires.
I only used it for negative/ground so no need for cover.

My positive is 2 cables off positive terminal to two fuses. Two cables off each fuse to inverters. The fuse holder came with covers.

The only covers I've made were recycled heater hose split lengthwise. Those are for the battery connections. Radiator hose might cover a busbar. Or plastic pipe.
 

1pt21GigaWatts

New Member
I got the bus bars recommended by and linked to from Will: Here

They're pretty solid. Tin plated copper bar, 3/8 studs, enough spacing for wide 4/0 contacts, 300A continuous.

$40 + $10 shipping for the pair.
 

MurphyGuy

Solar Addict
I can't bring myself to cut a notch in the lug with a Dremel with so much time until these batteries come in.
You better get accustomed to doing things like that if you're building DIY projects or your life is going to be expensive and miserable.
 

HighTechLab

Small Business Owner
I got the bus bars recommended by and linked to from Will: Here

They're pretty solid. Tin plated copper bar, 3/8 studs, enough spacing for wide 4/0 contacts, 300A continuous.

$40 + $10 shipping for the pair.
Source: Seller of these bars

I specifically sourced these bars because I was quite unhappy that the 4 stud bars previously noted in this thread would not let my 4/0 ring terminals fit and use the screws at the same time. These solve this problem with a shorter overall length.

I use these in my lab on my test & measurement rack all the time, with some pretty serious currents & cables. I've noticed my shunt getting far hotter than the bars ever do. They are great.

The only thing I will say you should be careful of is that all of the stud hardware is stainless steel, so if you overtorque the snot out of them, there is a chance they gall up and then it's a bit of a pain to get them apart. I've never had this happen, but in my previous job building foodservice stainless steel kitchen equipment, it was a common occurrence with stainless hardware. Anti-seize helps prevent this issue from ever happening. Same goes for stainless battery screw terminals as well.
 

chrisski

Photon Sorcerer
The only covers I've made were recycled heater hose split lengthwise. Those are for the battery connections. Radiator hose might cover a busbar. Or plastic pipe.
That is a perfect idea. I think I heard you mention this before. This will just be one stud longer than the others to secure hose or pipe cut in half. With the copper about $1 per inch for the 250 amp type, those female insulators about $6 each, and foor of PVC cut in half, and a few bolts and nuts for studs, this will probably come out to $30 -$40 for a larger busbar pair. Maybe 1/2 to 1/4 the price of a blue sea busbar.
 

HRTKD

Boondocker
This chart shows the relative conductivity comparison between different metals (of the same size). Is nickel twice as good as brass? The chart doesn't answer that question. When sizing aluminum bus bars, I did compare them to copper and the aluminum was 54% as conductive of the same size copper. To get equal conductivity, the aluminum has to be much bigger. You also have to take into account which allow of aluminum too.

1632852393385.png
 

Stepandwolf

Solar Addict
The insulators were what I was looking for. A couple more questions. Seems like you’ve done this before.

Now, how do you cover these. I can only come up with some homemade cut ABS plastic. Pretty sloppy.

Second, how do you secure the studs? Of course I could drill and use a bolt and nut, but I’m sure that’s best. 1/4 inch may not be enough to drill and tap.
I got some from AZ and they have clear plastic covers over the terminals.
 
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