Everything to bus bars?

[Chotu]

Electrical system is growing and it's time to start moving away from the temporary system.

To Do:
*Hook inverter up properly-still using temporary jumper cable setup. Lolol
*Bring second solar charge controller/other half of array online
*Organize wiring
*Run distributed wiring trunk lines
*Wire up new distribution panel at helm for all outside lighting/nav lights
*Get the BlueSea battery fuse on the battery terminal
*Cut hole in battery box and set up computer fan to blow interior air into box to keep above freezing
*Put thermometer in to be sure the batteries are above freezing to charge

Back at the battery area, all of these things need to attach to the battery bank and battery monitor shunt. It's becoming too crowded to have anything else going directly to the shunt.

I have some nice BlueSea heavy duty bus bars. Big, heavy ones with beefy connections.

Any issues hooking everything (both charge controllers, inverter, distributed system trunk, etc) to a positive and negative bus, then hook the bus to the battery bank and shunt?

i’m thinking this is fine but are there any issues with the charge controllers? That’s my main concern. They can be hooked right together? On the same connector?

[pcmm]

Originally Posted by Chotu

I have some nice BlueSea heavy duty bus bars. Big, heavy ones with beefy connections.

Any issues hooking everything (both charge controllers, inverter, distributed system trunk, etc) to a positive and negative bus, then hook the bus to the battery bank and shunt?

i’m thinking this is fine but are there any issues with the charge controllers? That’s my main concern. They can be hooked right together? On the same connector?

That would be the normal way its done. Battery posts should have no more than 4 connects per lug. If you need more you take the lead to a bus bar (and fuses) and power from there. Same for the negative side. I have 2 24 position Negative bus bars connected in series to take all the negatives from most of the loads. that is connected to a heavy duty Negatve bus bar that is directly connected to the load side of the shunt. Connected to that one is the Negative from the Engine, Windlass, chargers (shorepower, PV, etc) and any other high load devices. from the Shunt I have only 1 2/0 connection to the house bank main negative post.

[Chotu]

Originally Posted by pcmm

That would be the normal way its done. Battery posts should have no more than 4 connects per lug. If you need more you take the lead to a bus bar (and fuses) and power from there. Same for the negative side. I have 2 24 position Negative bus bars connected in series to take all the negatives from most of the loads. that is connected to a heavy duty Negatve bus bar that is directly connected to the load side of the shunt. Connected to that one is the Negative from the Engine, Windlass, chargers (shorepower, PV, etc) and any other high load devices. from the Shunt I have only 1 2/0 connection to the house bank main negative post.

Cool!

That’s exactly my plan. Just how you did yours.

thank you. I just wanted to put it all out there in case there were any unknowns that I was going to run into or funny ABYC regs. I should probably take a glance at those before starting to see if anything stands out.

I was especially worried that the solar charge controllers could fight each other, but, logically I guess that doesn’t really make much sense because ground is ground. And the positive potential coming out of the bank is the positive potential coming out of the bank. So however you hook them up it doesn’t make a difference.

Thankfully, my electrical set up is fairly simple. No engine. No windlass. but I do have a 6 kW pure sine inverter, 90 amp battery charger and 70 peak amps of solar charging to account for. The rest is just small loads like autopilot, LED lights, electronics, etc - which are part of the distributed system.

thanks for confirming the plan

[rslifkin]

My house bank also has a positive and negative bus. Flow is batteries -> switch -> positive bus. And negative bus -> shunt -> batteries. Having bus bars to handle all of the connections is the cleanest way to do it in my mind.

[Chotu]

Well, it’s a slam dunk here. Great! I agree that it’s the most clean way to do the connections.

I had already put together a small bus for the positive side, but the shunt is taking all the negatives right now. Not great.

And... that jumper cable that I have for my inverter is no good. If I put a load on the size of a heat gun or a microwave the jumper handle smokes. Lol. too much current through too small of a surface area on it. it’s quite the piece of crap. so I have been looking to replace that for quite some time now. what I do now is I just don’t put big loads on the inverter to prevent that from happening. I run the generator when it’s time to microwave or use high powered things like that. This electrical system upgrade will get everything going properly

[Putt-Putt]

If indeed your inverter can output 6 kW (VA) that means in could draw 500 Amps at 12 V.

Other than the a few Blue Seas buss bar models that are rated at 600A or greater, the rest of the components to provide that much current to the inverter are generally outside of the regular offerings of marine electrical suppliers. For example, 4/0 UL1426 conductors are limited to 445A, MRBF fuses limit at 300A, and even Blue Seas Class T fuses limit at 400A. Let's forget the AIC ratings for the moment.

You could double everything up and maybe be compliant if done carefully (never my first choice) otherwise you would have to source the properly sized components from an industrial supplier.

250 MCM is the next larger conductor available perhaps it would carry the current safely, but you would likely have to give up the strand count requirement.
Class T fuses are offered with ratings of more than 400A but they won't fit in the Blues Seas fuse holder, they are too big. Properly sized holders are offered.

Whatever you do, think it through and implement a safe, compliant and reliable electrical system.

[Chotu]

like most electrical items, I get something bigger than what I need. There is not a prayer in the world of needing 6 kW. Lol. 3kw is the absolute maximum load that could ever be run.

And that is if you are dumb enough to turn on the microwave, a heat gun, and a hairdryer.

Like most things electrical that I use, I oversize things so they are not stressed. Just like my wiring. It’s always oversized so it’s not stressed (and less voltage drop)

And as you are probably well aware, that’s a BS number anyway. That’s the surge rating. It can do that for just a second or two - maybe. But the inverter would probably explode

I’m at the 300A level with the system

[SailingHarmonie]

Originally Posted by Chotu

l

I’m at the 300A level with the system

The nameplate capacity of the inverter really does not matter IF (and only if) you size the fuses for the actual current carrying capacity of the wires feeding it.

If you use a 2/0 wire to feed your inverter, you need a fuse of 330A, or less.

The downside (of course!) is if you ever do ask the inverter to supply more power than that, the fuse blows after a few seconds. How frequent and annoying this is, is entirely for you to decide.

You describe the bus bars you have as "big", "heavy", "beefy." That is very much subjective, and not really enough information to decide. Some people's idea of what is "beefy" will be different than others. Are they 300Amp rated (or better)?

The use of bus bars is 100% standard practice, and is so for a lot of very good reasons. You should not consider anything else.

[Madehn]

Plan sounds good. Locate the bus bars where they are easy to get to as you will add loads as time goes on. Likewise fuses. Positive from charge controller to battery needs large amperage fuse as well close to battery. I also have on off rotary switches on main battery cables so I can shut down all power in an instant if needed. Inverter positive should also be fused and have an off/on high amperage switch. Best of luck sounds like you are making headway.

[Chotu]

It’s a 3KW system, not a 300A system. I hadn’t looked at all the gear in years.
So, 250A items. The fuse for the battery seems to be 300A

[rslifkin]

Keep in mind an inverter isn't 100% efficient. 300A is about right for fusing a 3KW inverter, especially once a bit of short term surge rating is taken into account. My 2kva Victron has a 200A breaker feeding it, although Victron actually recommends a 300A fuse.

[Chotu]

Originally Posted by Madehn

Plan sounds good. Locate the bus bars where they are easy to get to as you will add loads as time goes on. Likewise fuses. Positive from charge controller to battery needs large amperage fuse as well close to battery. I also have on off rotary switches on main battery cables so I can shut down all power in an instant if needed. Inverter positive should also be fused and have an off/on high amperage switch. Best of luck sounds like you are making headway.

Fuse is going on the battery list itself. It’s all BlueSea stuff.
Good call on the inverter cable fuse since it’s smaller than the battery cables.
Thanks! Gives me something to do while I wait for the crane. Also, solar insolation is declining rapidly so it’s time to get the full solar array online. I’ve only been using half of it since I left the dock nearly a year ago.

[Chotu]

Originally Posted by rslifkin

Keep in mind an inverter isn't 100% efficient. 300A is about right for fusing a 3KW inverter, especially once a bit of short term surge rating is taken into account. My 2kva Victron has a 200A breaker feeding it, although Victron actually recommends a 300A fuse.

Yeah, but I only use 1.5kw at the absolute maximum if someone decides to do a hairdryer through the inverter.

I’m not running 3kw so I’m not buying all new components. Unless the checks are coming in from the forum. Lol. You know how I get with that stuff.

I didn’t purchase the inverter positive side fuse/breaker yet so I can size that to knock out before the inverter reaches higher wattage. Since it never will, that won’t be an annoying thing to reset.

The highest load my inverter sees is a microwave, heat gun or shop vac. That’s it. And they aren’t on at the same time. Oversize so it can relax and have an easy time putting out the small amount of power that it puts out.

Electronics have a certain rating to them, if you want them to last for a long long time, you just oversize things. That keeps them from getting hot and keeps them from deteriorating over time. That’s why I have a big inverter. Plus it was a good deal for a pure sine

[flee27]

You mention ABYC. If you want to be up to their standards you definitely need to do some reading/gain some understanding of their standards. Especially if you have lithium. ABYC E13 standard for lithium has some specific standards over a lead system.

I am a "professional" DIY that is finishing up my rewire. I have done my best to understand and comply with ABYC E13 but definitely don't claim to be an expert.

And you definitely can get Class T fuses larger than 400 amps if needed. If you are working with 12 volts you almost certainly will need larger.

Good luck

Foster

[Chotu]

Good Point. I have to crack open the ABYC and see what’s going on with that. I’m not going to do any of their lithium stuff because it sounds pretty stupid from what I read on the forum. So I’m just treating them as lead acid batteries.

They have been treated as a lead acid batteries the whole time so I don’t think it’s going to make any difference when I improve the wiring around them.