LiFePO4 reference diagram, Alternator version

[znep]

Originally Posted by s/v Jedi

Label? It is a picture of an actual Balmar smart regulator!

FWIW, I agree that it would be easier to understand with more labels and not just images. There isn't a big difference if you already know what a component is, but if you don't it really is just a "blue blob" in the diagram at the resolution posted at the start of the thread.

[s/v Jedi]

Originally Posted by JRM

This tracks quite closely with what I have sketched out for myself initially, however as I work on actually installing it, I would like to bounce a few variations off the collected wisdom here. Boat is a 40' monohull.

I've moved my house batteries from the engine space into a newly built compartment that is on the opposite side of the boat. I've upgraded from golf carts to drop in LiFePo for a total of 800Ah. All Victron goodies, very similar to the diagram. A lot of the equipment is stuff we cruised with (on a trawler), but I'm taking with me as I re-refit a sailboat (long story.) Upgrading to electric galley "soon..."

The original starting battery is a Group 31 AGM that is just foreward of the engine space on the starboard side. Originally charged with a Blue Seas ACR that has been removed.

Trying not to outhink myself, but the original windlass wiring terminates just aft of the starting battery (at the old house bank.) My plan is to run the alternator output to the starting battery and use an Orion to the house. It's a 120 amp alternator, but it won't last long charging LiFePo at that rate. I can either extend the windlass cables about 20' (40' run total) to the new batteries, or upgrade the starting battery to a 4D to also run the windlass. The starting battery needs to be replaced regardless, and there is plenty of room for the larger battery. Your reference diagram shows the windlass running from the house positive bus. This I can do, but I rather like the idea of keeping the windlass on a traditional lead acid battery to account for the possibility of a load spike if/when the motor loads up. The estimated transient current max for my windlass size is within the spec of my total BMS OCP (400A), so it boils down to the cost delta for the additional 2/0 wiring or larger battery. And the PITA of running it.

Is there something I'm missing? Am I using the max draw argument realistically or am I just trying to confirm my desire not to run another set of 2/0 cables?

Thanks in advance,

JRM

I think my diagram shows exactly what you need: replace your start battery with 2x Odyssey PC2100 batteries, with the fuses and switch as per diagram. These fuses mount on the battery terminal: https://www.bluesea.com/products/519...k_-_30_to_300A
And the switch: https://www.bluesea.com/products/900...Battery_Switch

These two batteries are serious, make no mistake: each can deliver 6,000A current iirc and while optimized for starting, they can be a backup for other duties too…. like a windlass.

For the windlass I do recommend to connect to the house batteries. I believe your BMS will handle the inrush current.

This will give you options on what to do for the windlass. I don’t like the limits from MOSFET based BMS’s so I can see how you would prefer to use the start bank instead.

[s/v Jedi]

Originally Posted by znep

FWIW, I agree that it would be easier to understand with more labels and not just images. There isn't a big difference if you already know what a component is, but if you don't it really is just a "blue blob" in the diagram at the resolution posted at the start of the thread.

The problem is that labels take too much room, which is why some manufacturers have started using pictures and it’s a hit so you will see this more and more.

Also, you can deduct what it is. You clearly see an alternator with a big red cable so that would be the positive output; the switch would be the service disconnect and it goes on to a fuse and the positive busbar.

Then there’s a small wire coming from the alternator… what can it be… it must be the regulator. So even when I would have never seen a Balmar regulator before, I still know it’s a regulator.

About resolution: the forum changes resolution, but you can zoom in pretty far…

[s/v Jedi]

Originally Posted by zurk

lol. interesting take.
1. yes i have a cat obviously.

2. i could install an A/B switch but it just adds more wiring. if i really need to i can flip cables manually from one to the other since the start batteries for both engines are located together within 2 feet of each other.

3. All my batteries are 460Ah not 260Ah. I have 2 x 460Ah house and 1 X 460Ah start batteries for each engine (2 start total). So a total of 4 x 460Ah batteries.

Yes they are all LiFePO4. The reason for that is the start batteries always power network, bilge pumps and engine start so there is always a minimum 50W draw on them 24 x 7. A batteryprotect cuts them off at 60% should they get excessively low.

No they wont be fully charged as they have a constant draw down. also no AGM because an AGM wont be able to handle my engine start and network power.

4. Yes obviously mega fuse but im skipping the disconnect switches since i have batteryprotect instead.

The start batteries are always full because they are being float charged by the dc-dc converters?

If the batteries are that close together (I was thinking each in a hull) then I recommend the setup of the diagram of course. You get isolation of a potentially bad battery by the turn of a switch, can start engines from either battery etc.

Adding wiring for important tasks is a good thing. When you find yourself at anchor during a violent squall that threatens to set you on a rocky lee shore, it’s not a time to rewire something to start engines.

Your setup with 2x 460Ah LiFePO4 start batteries is peculiar; I have never seen such a thing before, never heard of it either. Your engines will start from a single 100Ah Odyssey battery.

[Sailmonkey]

Originally Posted by zurk

actually mine are modern batts so they self balance. they have +,- and CAN terminals and you run canbus wiring between them.

What’s not modern about prismatic cells?

You chose to spend a bunch of money on packaged cells with a built in bms….maybe good, maybe bad….who knows.

Others choose to purchase prismatic cells and add a bms of their choice. As well as external monitoring.

I’m in the build my own with components of my own choice.

Btw…..I’d welcome the opportunity to read about an alternator regulator that includes a BMS.

[zurk]

Originally Posted by Sailmonkey

What’s not modern about prismatic cells?

You chose to spend a bunch of money on packaged cells with a built in bms….maybe good, maybe bad….who knows.

Others choose to purchase prismatic cells and add a bms of their choice. As well as external monitoring.

I’m in the build my own with components of my own choice.

Btw…..I’d welcome the opportunity to read about an alternator regulator that includes a BMS.

correct. i would prefer a packaged solution with warranty.

look at the WS500 which ive posted about.

Wakespeed Products

[zurk]

Originally Posted by s/v Jedi

The start batteries are always full because they are being float charged by the dc-dc converters?

If the batteries are that close together (I was thinking each in a hull) then I recommend the setup of the diagram of course. You get isolation of a potentially bad battery by the turn of a switch, can start engines from either battery etc.

Adding wiring for important tasks is a good thing. When you find yourself at anchor during a violent squall that threatens to set you on a rocky lee shore, it’s not a time to rewire something to start engines.

Your setup with 2x 460Ah LiFePO4 start batteries is peculiar; I have never seen such a thing before, never heard of it either. Your engines will start from a single 100Ah Odyssey battery.

no the start batteries are always at 80% full or less because they are being continuously charged and discharged and the charging is software limited. the house batteries are each in a hull, the start batteries are basically sitting next to each other.

yes they would start with a 50Ah lead acid....1.4KW peak to start i believe..but thats not what they are doing regardless. they are for starting and also bilge pumps and network which draws 100Ah/day, give or take.

[toolbar]

Originally Posted by zurk

Yes they are all LiFePO4. The reason for that is the start batteries always power network, bilge pumps and engine start so there is always a minimum 50W draw on them 24 x 7. A batteryprotect cuts them off at 60% should they get excessively low.

Do your bilge pumps run continuously? Or why is there always a 50W draw? What is this "network"? My Wifi-WLAN-router and the entire NMEA2000 network on my boat draws about 2 amps (plus Plotter).

I feel that 440AH Lifepo4 starter batteries are extremely wasteful. Even more wasteful than the alleged "gold plated" BMV devices you talked about earlier for 1000 EUR each. :-) I can't think of a good reason for anything much bigger than a simple 44AH lead battery on our old catamaran and I would much rather use those two huge Lifepo4 batteries for house loads.

Paul

[Baronkrak]

Originally Posted by zurk

no the start batteries are always at 80% full or less because they are being continuously charged and discharged and the charging is software limited. the house batteries are each in a hull, the start batteries are basically sitting next to each other.

yes they would start with a 50Ah lead acid....1.4KW peak to start i believe..but thats not what they are doing regardless. they are for starting and also bilge pumps and network which draws 100Ah/day, give or take.

Are the start batteries under a BMS control?

[Sailmonkey]

Originally Posted by zurk

correct. i would prefer a packaged solution with warranty.

look at the WS500 which ive posted about.

Wakespeed Products

So you prefer packaged……doesn’t make it better. It makes it more like windows vs Linux. Both work. Doesn’t make one better than the other.

Regarding the wakespeed…….there is NO BMS integral to the regulator. It’s able to communicate with a BMS. Other than not needing external switching from a BMS like a Balmar, it’s just another alternator regulator.

[zurk]

Originally Posted by toolbar

Do your bilge pumps run continuously? Or why is there always a 50W draw? What is this "network"? My Wifi-WLAN-router and the entire NMEA2000 network on my boat draws about 2 amps (plus Plotter).

I feel that 440AH Lifepo4 starter batteries are extremely wasteful. Even more wasteful than the alleged "gold plated" BMV devices you talked about earlier for 1000 EUR each. :-) I can't think of a good reason for anything much bigger than a simple 44AH lead battery on our old catamaran and I would much rather use those two huge Lifepo4 batteries for house loads.

Paul

no bilge pumps are connected to float switches. its a PoE network with fiber backbone and starlink/5G loadbalanced through a router. it takes power to run it since its dumping a lot of high speed data and power through it.
my digital network is a lot more complicated than yours since i use it for work and it needs to work 100% all the time.

[zurk]

Originally Posted by Sailmonkey

So you prefer packaged……doesn’t make it better. It makes it more like windows vs Linux. Both work. Doesn’t make one better than the other.

Regarding the wakespeed…….there is NO BMS integral to the regulator. It’s able to communicate with a BMS. Other than not needing external switching from a BMS like a Balmar, it’s just another alternator regulator.

it will ramp up and ramp down charge as required. the internal battery BMS does the balancing and all the rest. it does make it better since there are less connections to worry about and its a manufactured solution in a box as opposed to DIY.

[zurk]

Originally Posted by Baronkrak

Are the start batteries under a BMS control?

all the batteries have their own BMS and the battery BMSes are all networked to each other via hard line (CAN bus). the start batteries go through a victron dc to dc charger.

[Sailmonkey]

Originally Posted by zurk

it will ramp up and ramp down charge as required. the internal battery BMS does the balancing and all the rest. it does make it better since there are less connections to worry about and its a manufactured solution in a box as opposed to DIY.

For you a manufactured solution is better……for others it’s not. A diy solution does the same things your purchased system does, for less money and with greater flexibility.

So all your previous berating of Jedi looks more like someone who is trying to justify their expensive choices.

[newhaul]

Originally Posted by zurk

it will ramp up and ramp down charge as required. the internal battery BMS does the balancing and all the rest. it does make it better since there are less connections to worry about and its a manufactured solution in a box as opposed to DIY.

No more actual connections but DIY has more flexibility wrt repairs.

Question is what are you going to do when one of those internal BMS units die an unnatural death? Battleborn even admits this is the reason for 90% of their warranty failure claims