Check my schematic please. New Victron system on Leopard Catamaran.

[FlyingScot]

Looking for feedback. I drew this system up over the weekend using canva.com. We use this program for website stuff so it may not be the best for this but it was familiar.

Big refit in progress. New Yanmar 3YM30AE (no computer) with SD25 saildrives. These come with dumb Valeo 125A alternators. One per engine.

Please review the drawing and let me know of any errors. I'm also interested in better, cheaper, easier, easier to install methods that accomplish the same goals.

PDF is 11.3 MB so I can't upload here.

Here is a OneDrive link. https://onedrive.live.com/?authkey=%...130246&o=OneUp
Thanks!

[SV_FlyingTigress]

Very nice schematic. I can't technically comment as I am in the learning curve but can see you did a great job. I would like to create something similar for my work so my questions are:
1) what design software did you use and
2) any chance you could share your drawing file?

Thanks,


Stephen

[FlyingScot]

Originally Posted by Stephen_MO

Very nice schematic. I can't technically comment as I am in the learning curve but can see you did a great job. I would like to create something similar for my work so my questions are:
1) what design software did you use and
2) any chance you could share your drawing file?

Thanks,


Stephen

Thanks for the compliment. I used canva.com to create. Then saved as a PDF file. Not sure if it's possible to share. Canva costs like $80 a year or $13 a month IIRC.

[FlyingScot]

Updated the drawing. Anyone want to give some feedback? Don't be shy.
https://tinyurl.com/yp23k4uk

Chris
SV Cosmos

[Emmalina]

Would definitely put external controllers on your alts or your bms will take over and thats not good ! DC-DC charging is limited .

[FlyingScot]

The JPEG attached was the original not the updated.
We don't currently charge much from engines and don't plan to in the future either. I considered external regulation and will keep that as a future upgrade if needed. Thanks for your feedback.

[AllenRbrts]

I question the value of 5 solar controllers. The panels can be in parallel and shading will not effect the other panels. Seems like lots of wiring and hardware with little gain. I run 3 panels on one controller, works great. If much of this is a new install have you thought about have the core of the system at 24v? Lot smaller wire sizes.

[team karst]

I suspect disconnects on the MPPT's outputs are required for ABYC.

Well done drawing. I'd call it a great blend of a schematic and a wiring diagram.
Trying to get used to BLU as NEG also! Usually, that color is euro ac NEU.

[scargo]

I am not an electrical engineer. But an IT guy who likes simple (reliable) systems.
I too question the value of an MPPT per solar panel rather than a good marine combiner box (where you can turn on/off each panel) and one MPPT, maybe two in active/stand-by mode for redundancy.

[CaptainRivet]

Originally Posted by AllenRbrts

I question the value of 5 solar controllers. The panels can be in parallel and shading will not effect the other panels. Seems like lots of wiring and hardware with little gain. I run 3 panels on one controller, works great. If much of this is a new install have you thought about have the core of the system at 24v? Lot smaller wire sizes.

I am starting my LifePo4 install in my FP Lavezzi 40ft cat too

12V vs 24V: normally 24V but
I am in the same situation then you, new engines with new 12v alternators and starters, new overhauled 12V windlass and a quite new 12V watermaker….
Well it’s cheaper to stay 12V and have bigger cables directly from the 12V 5kw inverter to the LifePo4 and don‘t go on the main bus for that. So I can keep main positive bus to 150A continuous (all is speced for 300A) and the Max. 400A load from inverter goes straight to house LifePo4 with its own fuse.
Like this you don‘t have to size your main busbars that massive and as everything else has smaller fuses.
I use Electrodacus BMS and this has 2 shunts directly on the positive pole of the battery to measure what’s going in and out as no current flows through this BMS.
So on the 750A load side shunt I connect 3 fuses type NH3, one 300A for the main positive load Busbar and two 250A, one for each of the two 120mm2 cables to the inverter. Like this you stay below the common 300A continuous rating and things don‘t get hot. Highly recommend to use only NH3 fuses as main fuse, the mega fuse „toys“ melt away or create a lot heat problems with continuous loads above 150A….yes they have rated fuses till 400A

5 MPPT and bifacials:
Perfect choice bifacials, due to diffusion light they are much less prone to shading…on passage I have now 80% of my charge amps on anker.
My experience right thing to do with bifacial panels. Yes more effort for cabling but worth it. You get 2x6mm2 in one cable and this is easy to route, so 5 of them.
First Victron has only 85A and 150A MPPT, so 2 or 3 panels on one controller. Using 2 440W bifacial on the 85A MPPT will max it out quite frequently so life is shorter, 2nd cable getting quite big if you go to 150A version. Costs: you not saving much. 2nd if one controller breaks you loose 2-3panels, 880 or 1320W..oouch
More important 1 MPPT per panel can track much better as bifacials profit from more tracking then normal panels. I also have Victron MPPTs.
Have 3 panels Longli bifacial 365W (only front speced, backside delivers up to 25% additional) on 1 MPPT with 2 panels parallel delivered Max 790W and 1 panel on 1 MPPT which delivered 440-460W, means total 790+460=1250W. now having 3 MPPT on 3 panels so each on one MPPT I now see 440-460 from each of the 3 panels, means 3x460W=1380W. All 3 panels over the davits, only exchanged the 1 85A Controller to 2 x 50A and run an additional cable with 2x6mm2 to the 3rd MPPT, nothing else changed.

What’s that switch on the DC to Dc charger?
The Orion has a remote switch so you don‘t need a high current switch to interrupt charging manually, just switch it of via remote means put a switch via remote.
Like your wiring on the starter battery is set up now, if your BB starter dies you cannot switch over to the STB one.
I would put a combiner in if one engine, so 1 alternator is running the combiner connects both it is charging both starter BB and STB. That’s how it’s normally set up already with lead batteries in cats. 1 hull is normally starter+house, the other is only starter and when you run one engine both sides will be combined. You can keep it like this and just put both DC-to-DC charger in parallel on the Hull side where your old house+starter was/is and thats most like where your new LifePo4 will be installed too, typically BB. So if you run one engine both DC-to-DC charger will charge=60A, your 125A one can handle this. If you run the STB engine the Batterie combiner will combine both starter bat and the 2 DC-to-DC starter will start charging too. If you run both engines the same but the charge load is shared.

[FlyingScot]

Originally Posted by AllenRbrts

I question the value of 5 solar controllers. The panels can be in parallel and shading will not effect the other panels. Seems like lots of wiring and hardware with little gain. I run 3 panels on one controller, works great. If much of this is a new install have you thought about have the core of the system at 24v? Lot smaller wire sizes.

I currently have 4 panels and 4 controllers and absolutely love how they react to any changes, love how you can see individual panel output and love how if any one fails, you don't lose a huge portion of your harvesting capability. Also, you don't save any money by having fewer larger controllers and you make the price of keeping a spare much higher.

Originally Posted by team karst

I suspect disconnects on the MPPT's outputs are required for ABYC.

Well done drawing. I'd call it a great blend of a schematic and a wiring diagram.
Trying to get used to BLU as NEG also! Usually, that color is euro ac NEU.

From what I can tell and read, there is not a requirement for self limiting devices to have a fuse or breaker, just a disconnect, which can be the wire itself at the controller. Think of it this way, the fusing is to protect the wire. If your wires can safely handle the max amps that the panel can produce, then there is nothing to protect. The wires should be oversized for minimum voltage drop and max efficiency anyways. The panel can't make more than it can make.

There are valid reasons to have a breaker or fuse, especially if it makes it easier to isolate the panels. But what I love about solar is you don't have to mess with it after a good installation. You can just let it make power day after day after day.

Originally Posted by scargo

I am not an electrical engineer. But an IT guy who likes simple (reliable) systems.
I too question the value of an MPPT per solar panel rather than a good marine combiner box (where you can turn on/off each panel) and one MPPT, maybe two in active/stand-by mode for redundancy.

Every connection adds cost, complexity and failure points. Each connection creates loss in the system. More controllers means more redundacy. I think you are looking at it wrong, but everyone can see benefits in different ways. See some of my above comments.

I've updated the drawing to reflect some feedback I have recieved in other places. I appreciate all of the feedback so far and hope everyone will benefit from the discussion and I end up with a safe and reliable system.

New drawing and link to new high resolution PDF: https://tinyurl.com/2p8az2k9

Some of the changes were adding Class T fuses since the Victron Lynx only holds Mega fuses which aren't safe enough in a lot of people's opinion including mine now. I'll try to mount them in the look alike device Lynx Power In (vs. Distributor).

[FlyingScot]

Originally Posted by CaptainRivet

I am starting my LifePo4 install in my FP Lavezzi 40ft cat too

12V vs 24V: normally 24V but
I am in the same situation then you, new engines with new 12v alternators and starters, new overhauled 12V windlass and a quite new 12V watermaker….
Well it’s cheaper to stay 12V and have bigger cables directly from the 12V 5kw inverter to the LifePo4 and don‘t go on the main bus for that. So I can keep main positive bus to 150A continuous (all is speced for 300A) and the Max. 400A load from inverter goes straight to house LifePo4 with its own fuse.
Like this you don‘t have to size your main busbars that massive and as everything else has smaller fuses.
I use Electrodacus BMS and this has 2 shunts directly on the positive pole of the battery to measure what’s going in and out as no current flows through this BMS.
So on the 750A load side shunt I connect 3 fuses type NH3, one 300A for the main positive load Busbar and two 250A, one for each of the two 120mm2 cables to the inverter. Like this you stay below the common 300A continuous rating and things don‘t get hot. Highly recommend to use only NH3 fuses as main fuse, the mega fuse „toys“ melt away or create a lot heat problems with continuous loads above 150A….yes they have rated fuses till 400A

5 MPPT and bifacials:
Perfect choice bifacials, due to diffusion light they are much less prone to shading…on passage I have now 80% of my charge amps on anker.
My experience right thing to do with bifacial panels. Yes more effort for cabling but worth it. You get 2x6mm2 in one cable and this is easy to route, so 5 of them.
First Victron has only 85A and 150A MPPT, so 2 or 3 panels on one controller. Using 2 440W bifacial on the 85A MPPT will max it out quite frequently so life is shorter, 2nd cable getting quite big if you go to 150A version. Costs: you not saving much. 2nd if one controller breaks you loose 2-3panels, 880 or 1320W..oouch
More important 1 MPPT per panel can track much better as bifacials profit from more tracking then normal panels. I also have Victron MPPTs.
Have 3 panels Longli bifacial 365W (only front speced, backside delivers up to 25% additional) on 1 MPPT with 2 panels parallel delivered Max 790W and 1 panel on 1 MPPT which delivered 440-460W, means total 790+460=1250W. now having 3 MPPT on 3 panels so each on one MPPT I now see 440-460 from each of the 3 panels, means 3x460W=1380W. All 3 panels over the davits, only exchanged the 1 85A Controller to 2 x 50A and run an additional cable with 2x6mm2 to the 3rd MPPT, nothing else changed.

What’s that switch on the DC to Dc charger?
The Orion has a remote switch so you don‘t need a high current switch to interrupt charging manually, just switch it of via remote means put a switch via remote.
Like your wiring on the starter battery is set up now, if your BB starter dies you cannot switch over to the STB one.
I would put a combiner in if one engine, so 1 alternator is running the combiner connects both it is charging both starter BB and STB. That’s how it’s normally set up already with lead batteries in cats. 1 hull is normally starter+house, the other is only starter and when you run one engine both sides will be combined. You can keep it like this and just put both DC-to-DC charger in parallel on the Hull side where your old house+starter was/is and thats most like where your new LifePo4 will be installed too, typically BB. So if you run one engine both DC-to-DC charger will charge=60A, your 125A one can handle this. If you run the STB engine the Batterie combiner will combine both starter bat and the 2 DC-to-DC starter will start charging too. If you run both engines the same but the charge load is shared.

You'll see on the latest revision, I have added a combiner. I have reduced the chargers from 2 x 30A to just one per engine. Apparently the 125A alternator can't produce more than about 35A when hot. The line to turn off the charge source from the BMS is needed so the BMS has control over charging and discharging. Thanks for you feedback.

[SV_FlyingTigress]

Originally Posted by FlyingScot

I currently have 4 panels and 4 controllers and absolutely love how they react to any changes, love how you can see individual panel output and love how if any one fails, you don't lose a huge portion of your harvesting capability. Also, you don't save any money by having fewer larger controllers and you make the price of keeping a spare much higher.



From what I can tell and read, there is not a requirement for self limiting devices to have a fuse or breaker, just a disconnect, which can be the wire itself at the controller. Think of it this way, the fusing is to protect the wire. If your wires can safely handle the max amps that the panel can produce, then there is nothing to protect. The wires should be oversized for minimum voltage drop and max efficiency anyways. The panel can't make more than it can make.

There are valid reasons to have a breaker or fuse, especially if it makes it easier to isolate the panels. But what I love about solar is you don't have to mess with it after a good installation. You can just let it make power day after day after day.



Every connection adds cost, complexity and failure points. Each connection creates loss in the system. More controllers means more redundacy. I think you are looking at it wrong, but everyone can see benefits in different ways. See some of my above comments.

I've updated the drawing to reflect some feedback I have recieved in other places. I appreciate all of the feedback so far and hope everyone will benefit from the discussion and I end up with a safe and reliable system.

New drawing and link to new high resolution PDF: https://tinyurl.com/2p8az2k9

Some of the changes were adding Class T fuses since the Victron Lynx only holds Mega fuses which aren't safe enough in a lot of people's opinion including mine now. I'll try to mount them in the look alike device Lynx Power In (vs. Distributor).

Thanks Scott, great elaboration.

[SV_FlyingTigress]

Originally Posted by FlyingScot

You'll see on the latest revision, I have added a combiner. I have reduced the chargers from 2 x 30A to just one per engine. Apparently the 125A alternator can't produce more than about 35A when hot. The line to turn off the charge source from the BMS is needed so the BMS has control over charging and discharging. Thanks for you feedback.

FlyingScot: How is this project going; have you made any modifications? I am using your reference architecture to try to piece a smaller version that will fit on my Privilege 39

[FlyingScot]

Originally Posted by Stephen_MO

FlyingScot: How is this project going; have you made any modifications? I am using your reference architecture to try to piece a smaller version that will fit on my Privilege 39

I have made some radical changes to the design. Only one Multiplus, upgraded the alternators, added an efficient watermaker and aircons. Large wires, large bus bars, etc. to try and keep the efficiency up. Of course the goal is to have aircon in our cabin at night during those sticky times. One thing might change and that's the alternators.

Parts have been ordered. Now the waiting game begins.

Highly recommend Andre @Gulf Nautical / The Yacht Rigger in St. Pete FL.

https://1drv.ms/b/s!AvqJ-T1Ji55ziPgM...U6Ryg?e=Xfg7Cd