Need a bit of help with system design/setup

svsagres

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Why would I want a bms to talk to the cerbo, or what benefits would that offer me?
At the minimum, it makes the SOC display on the cerbo reasonably accurate. But more importantly, it integrates the charging/discharging of your batteries with the rest of the system. The BMS will then basically control how much charge your alternators deliver, how much power comes off the multiplus inverter/chargers, etc. in effect, done right, the protection systems provided as part of the BMS should never ever trip.
 

jbird526

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jbird526

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Still wonder @sandog if you are going to run your LFP and AGM in parallel as previously mentioned?

Looks alright. The one thing I would change is to put a 24V|24V DC:DC charger between your LiFePO4 bus and your two sets of AGMs. You don't want to hard-wire the AGMs in parallel with your LiFePO4 except, maybe, have the option to do that in an emergency. The DC:DC charger will properly charge and maintain the batteries, as they should spend most of their time idle.

Upgrading to the Wakespeed regulators is a positive regardless of the charge profile but wondering if this is a possible layout.
  1. Do not parallel the AGM banks and the LFP banks.
  2. Off each regulator use the AGM charge profile to charge the AGM banks.
  3. Off of Shorepower and one of the Gensets have AGM chargers for each AGM bank.
  4. Optional DC to DC off of LFP banks to supplement charging of AGM banks.
Do you normally have situations where you are using the Thrusters and NOT running the engines, whereby the alternators would be charging the AGM banks?

Never dealt with this large of a ship so I am ignorant and just trying to throw out alternate thought paths. My thought is leaving the ships systems to charge batteries related ship systems, ie: bow and stern thrusters, and leave solar, the occasional shore power and a Genset to charge house systems.

One thing I do not see is a mention of electronics, radar, marker lighting, etc. Assume coming off of 24VDC and 12VDC SubPanel? How much draw does all that add up to?
 

sandog

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Still wonder @sandog if you are going to run your LFP and AGM in parallel as previously mentioned?



Upgrading to the Wakespeed regulators is a positive regardless of the charge profile but wondering if this is a possible layout.
  1. Do not parallel the AGM banks and the LFP banks.
  2. Off each regulator use the AGM charge profile to charge the AGM banks.
  3. Off of Shorepower and one of the Gensets have AGM chargers for each AGM bank.
  4. Optional DC to DC off of LFP banks to supplement charging of AGM banks.
Do you normally have situations where you are using the Thrusters and NOT running the engines, whereby the alternators would be charging the AGM banks?

Never dealt with this large of a ship so I am ignorant and just trying to throw out alternate thought paths. My thought is leaving the ships systems to charge batteries related ship systems, ie: bow and stern thrusters, and leave solar, the occasional shore power and a Genset to charge house systems.

One thing I do not see is a mention of electronics, radar, marker lighting, etc. Assume coming off of 24VDC and 12VDC SubPanel? How much draw does all that add up to
I think I will be taking the batteries off of running parallel and adding individual chargers to the AGMs.

I would not see a situation where the thrusters are being used without the main engines being on, as they are typically used for docking maneuvers and mooring maneuvers.

For the rest of the electronics, loads I need to still sit down and calculate, as well as some of them measure. There are additional items I need to add to and calculate those loads. But mostly, I am viewing the loads, as just something that are there, and adding as many LiFePO4 batteries as makes sense as well as much solar as I can fit. My other boat that I brought up from St. Maarten to Ft Lauderdale, had 14 type 31 AGM batteries for house, and the runtime and lack of running AC units and Oven/Cooktop without running the generator, allowed me not enough runtime, so had to run the generator pretty consistently, as we were traveling from early Sept to early Oct, and too hot to live without AC. The generator, 16kw Northern Lights, burned about 2 gallons/hr, and figure 18 to 20 hrs a day, and diesel fuel ranging from $3.15/gallon to $6.75/gallon, and you have an average expense of $200/day for electricity. That was for a 1800 mile journey, this one is going to be 6000~8000 mile journey (depending on how many "detours" we take and avoiding running the generator for any length of time helps to pay for this system quickly.

The big loads, lighting, refrigeration, Air Conditioning, cooking, dive compressor, and communications, I will for sure calculate out as. As it is a motor cruiser, I am hoping solar and the two engine alternators can supply most of the input power to the battery banks, with the occasional 5kw generator needing to top things off in a pinch. With the 20kw generator as a backup that does not need to be used. Or even better yet, just top up with shore power occasionally as needed when docked or refueling.
 
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svsagres

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Does anyone have any thoughts on this?
If it was me, I’d stick with Victron. They’re very rugged, and common in the marine environment. And like with everything else, integrating everything together makes for a much easier to manage system. That said, you might want to look at the quattros which will do 5kva on 24v rather than 3kva.

A own needs are much more modest, given that it’s going on a 27’ sailboat.
 

jbird526

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If it was me, I’d stick with Victron. They’re very rugged, and common in the marine environment.
I have to agree that in a marine environment you should stick with Victron. I do not say this lightly but do you want to put your life in the hands in a non tier 1 product? Growatt is not a tier 1 product like Victron has shown itself to be. Will probably get some flames for that comment and I am ignorant and Victron is no longer tier 1.

I spend some time in the FLA keys and US Virgin Islands each year and most boat owners I speak to, that can afford it, use Victron or wants Victron for a reason. There must be a real world reason for that sentiment.

All of my previous comments or questions that I throw out are based ONLY on regards for your safety. I would love to be in your position and would hope that everyone in this community is not trying to sell you on their ideas because they want to be "right", rather on you making your trip in the safest and trouble free manner as possible.

Again, have not worked on a project with as many varied power sources as you are presented. I try to ask questions to at least prompt a thought process and perhaps others that are more experienced can provide concrete solutions.
 

sandog

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If it was me, I’d stick with Victron. They’re very rugged, and common in the marine environment. And like with everything else, integrating everything together makes for a much easier to manage system. That said, you might want to look at the quattros which will do 5kva on 24v rather than 3kva.

A own needs are much more modest, given that it’s going on a 27’ sailboat.
I was originally looking at the Quattros, unfortunately, they run a bit more than multipass, for $/w. I believe the only real difference between them is the Quattro is the ability to automatically switch from two different ac sources. I also may need to bump up to 12 to 15kw of inverter availability.
 

sandog

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I have to agree that in a marine environment you should stick with Victron. I do not say this lightly but do you want to put your life in the hands in a non tier 1 product? Growatt is not a tier 1 product like Victron has shown itself to be. Will probably get some flames for that comment and I am ignorant and Victron is no longer tier 1.

I spend some time in the FLA keys and US Virgin Islands each year and most boat owners I speak to, that can afford it, use Victron or wants Victron for a reason. There must be a real world reason for that sentiment.

All of my previous comments or questions that I throw out are based ONLY on regards for your safety. I would love to be in your position and would hope that everyone in this community is not trying to sell you on their ideas because they want to be "right", rather on you making your trip in the safest and trouble free manner as possible.

Again, have not worked on a project with as many varied power sources as you are presented. I try to ask questions to at least prompt a thought process and perhaps others that are more experienced can provide concrete solutions.
I do appreciate the concern, and I figure the questions get you more to what I am trying to do, as I am sort of figuring out some of the details still. I do appreciate all of the help and insight. So please continue asking away or recommending ideas or items.

I have never worked on a project like this either, but work from home, need to do the most with it. And normally I would say I would run the generator, but my past experience has shown that is a very, very expensive proposition, so put the money into this system rather than waste it on diesel and wear and tear.

When I am done, I will be posting pictures of the setup as well as final wiring diagrams. I also think beyond the Victron display, I will have a surface tablet mounted to the wall in the engine room to be able to monitor and control many of the items, and have it linked to a MFD.
 

jbird526

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@sandog Have you drawn up how things will look with the LFP and AGM on separate charging systems? Also what are you using to draw your diagrams? They have been done up nicely and may help others to use similar, as some diagrams are just horrible to try and read.
 

sandog

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@sandog Have you drawn up how things will look with the LFP and AGM on separate charging systems? Also what are you using to draw your diagrams? They have been done up nicely and may help others to use similar, as some diagrams are just horrible to try and read.
I need to make the few modifications we have discussed, then will update. Have been dealing with plumbing and welders today to start prepping those trades up.

Thank you for the compliment, the program I use is CorelDraw, but Visio or AutoCad would have worked as well. I was initially doing photos of them but found them too time-consuming for mocking up. When it comes to final working drawings, I may produce more details just to simplify my life, but depends on the time I have, as I need to get the boat off the hard and into a marina outside of Houston, so I can bring my mechanic, my shipwright, and my marine plumber from St. Maarten in to start to prep the mechanicals. If anyone is in the Houston area, let me know.
 

GnrlPatton

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Sep 23, 2020
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Thanks so much for your diagram, I'm working on my own setup and that made it very easy to use as a starting point. I'm also looking at going all Victron, so far I've settled on the MultiPlus inverter/charger, MPPT, Cerbo and Smart Shunt. I had a question about the Smart Battery Protect in your diagram. Looking at the details for it, it says that they are not designed for reverse currents from charging sources. I think that is exactly what the MultiPlus would be, so I wonder if that wouldn't work in your setup. Thoughts?

I need to figure out a solution for the alternator charging, I'm planning to keep my current house charger for just the starting batteries, and using the MultiPlus for just the house bank. I think if I route the alternator charging through the starting bank, and then from the starting bank to the house bank. That would give the overcharge protection to the alternators I think. I definitely don't want to burn up my alternators.

Kevin
 

captainrivet

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Jan 27, 2020
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For this complex and high current install I highly recommend a Taos BMS.
Huge advantage compared to Victron is that no current flows through the BMS. And 11kw of bowtruster will kill every BMS that carries current instantly due to its high surge.
 

sandog

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Nov 20, 2021
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We need pics of this boat or it didn't happen. 😊
(Lifetime boater. At least tell us what KIND of boat.)
Here is my new boat that I am putting this system into. It goes in for paint next week, then mechanical and plumbing systems, then should be splashed and heading towards the canal hopefully by mid to late May.

20220305_122220.jpg20220305_122209.jpg
 

sandog

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Downeast or Mainship?
Like. (y)

You have some nice waters for cruising. All of my experience is in the PNW. Very different experience.

The new one is a BIG boat. Hard chines - is it steel?
The Eastern Caribbean was beautiful! Though challenging due to shallow coral heads, and steep drop-offs for anchoring. Yes, the new one is definitely on the bigger side. Has about 1000 sq ft of living area inside, which is why I figured building it like a 1000 sq ft off-grid type house. For material, yes, 3/8" steel hull, 1/4" steel superstructure, 1" steel keel.
 
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