Merged LiFeYPO4 1000Ah Winston prismatic cells and all electric galley...

[SFH]

Going back to the initial topic for this thread.

I have adapted CatNewBee/SY Destiny baseline design to our Jeanneau 53. Relays are ML-RBS and the interface is the same as CatNewBee.

The only difference is that I have include a Victron Lynx power/Shunt/Distributor bar

The Lynx Shunt is on the CAN bus while the BMV shunt is basically only to control the legacy charge relay

I would appreciate any comments or inputs before I cut the cables and start connecting. Please see attachment

Thanks
Steen

[CaptainRivet]

Originally Posted by SFH

Going back to the initial topic for this thread.

I have adapted CatNewBee/SY Destiny baseline design to our Jeanneau 53. Relays are ML-RBS and the interface is the same as CatNewBee.

The only difference is that I have include a Victron Lynx power/Shunt/Distributor bar

The Lynx Shunt is on the CAN bus while the BMV shunt is basically only to control the legacy charge relay

I would appreciate any comments or inputs before I cut the cables and start connecting. Please see attachment

Thanks
Steen

There is no BMS, so no control on cell level, which is critical and crucial. Lynx BMS only works with Victron LFP batteries,no others.

You cannot charge LFP directly via yanmar alternator, it will be burned. you need an external regulator, a Argo Fet splitting diode+lead or AGM starter or a DC to dc charger. Except of the charge disconnect use Victron Battery protect which are SSR. Victron Lynx shunt cannot control latching relays like ML-RBS, so that doesn't work.
Let the BMV control the legacy charge relay is bad practice as you only control it on total battery voltage and not on cell level which is crucial. Especially the alternator is the dangerous charge source for a LFP if not controlled on cell level.

[SFH]

Originally Posted by CaptainRivet

You cannot charge LFP directly via yanmar alternator, it will be burned. you need an external regulator, a Argo Fet splitting diode+lead or AGM starter or a DC to dc charger. Except of the charge disconnect use Victron Battery protect which are SSR. Victron bms cannot control latching relays.

Thanks for your comments.

1. I am aware of the charge issue. The regulator is not shown in the drawing. No issue

2. I am not using Victron BMs but REC BMS. I have not shown the relay driver interface but it is there.

[CaptainRivet]

Originally Posted by CatNewBee

Sorry, 500A and 400A ANL fuses. Lost in translation. The circuits can be interrupted by the 500A BlueSea ML-RBS, so I used real fuses, not this fancy automatic breakers.

Good real fuses but check your short curcuit amps of your 1000AH Winston cells, thats gigantic and far above ANL rating, ANL is not enough if connected directly to the LFP.
You need NH3 or class T fuse.

[CaptainRivet]

Originally Posted by SFH

Thanks for your comments.

1. I am aware of the charge issue. The regulator is not shown in the drawing. No issue

2. I am not using Victron BMs but REC BMS. I have not shown the relay driver interface but it is there.

Then show your whole diagram with all details, we cannot read your mind here
Less relays as possible as they suffer mechanical issues, need a lot power and life only 300 cycles. If its permanent close it also ages and cycle life reduces. And they are freaking expensive.
Charging and reverse current flow is not possible with SSR, there you need a relay in your case, everywhere else suggest to use SSR.
Rec BMS has a shunt, so you don't need Lynx and BMV shunts. Every shunt is voltage drop on the whole system. Use BMV on your starter if you have one already, if not delete it from your system.

[SFH]

Originally Posted by CaptainRivet

Then show your whole diagram with all details, we cannot read your mind here
Less relays as possible as they suffer mechanical issues, need a lot power and life only 300 cycles. If its permanent close it also ages and cycle life reduces. And they are freaking expensive.
Charging and reverse current flow is not possible with SSR, there you need a relay in your case, everywhere else suggest to use SSR.
Rec BMS has a shunt, so you don't need Lynx and BMV shunts. Every shunt is voltage drop on the whole system. Use BMV on your starter if you have one already, if not delete it from your system.

Thanks CaptainRivet for comments. See attachment

A few comments:

1. I already have all hardware. No additional sourcing required. And I want to keep most of the existing infrstructure

2. I agree that ideally the legacy BMV712 shunt should be eliminated (dotted) but in that case I dont have a relay controller to manage the legacy SOC from legacy. The CERBO only have two analgue relays for generator and temperature
Any suggestions on improved solution?

3. The LYNX distributor already comes with fuses but I add Class T fuses right after the battery and right after the Quattro and then just add a MEGA fuse in the LYNX Shunt

4. The Quattro is a 12/5000. I have two 230V groups: One 32A for A/C and one 40A for SSB, Watermaker and galley etc.

5. The legacy charging provides a problem. I do have a 3-way MOSFET charge distributor in place but probably need to add an ORION charger. Alternative is to completely eliminate charging of housebank from legacy and only through solar and Quattro

6. The Quattro DCH ML-RBS is probably overkill but I keep it as second line of defence in case the CAN bus stops working. In that case the BMS will manage it

All inputs highly appreciated

[CaptainRivet]

Originally Posted by SFH

Thanks CaptainRivet for comments. See attachment

A few comments:

1. I already have all hardware. No additional sourcing required. And I want to keep most of the existing infrstructure

2. I agree that ideally the legacy BMV712 shunt should be eliminated (dotted) but in that case I dont have a relay controller to manage the legacy SOC from legacy. The CERBO only have two analgue relays for generator and temperature
Any suggestions on improved solution?

3. The LYNX distributor already comes with fuses but I add Class T fuses right after the battery and right after the Quattro and then just add a MEGA fuse in the LYNX Shunt

4. The Quattro is a 12/5000. I have two 230V groups: One 32A for A/C and one 40A for SSB, Watermaker and galley etc.

5. The legacy charging provides a problem. I do have a 3-way MOSFET charge distributor in place but probably need to add an ORION charger. Alternative is to completely eliminate charging of housebank from legacy and only through solar and Quattro

6. The Quattro DCH ML-RBS is probably overkill but I keep it as second line of defence in case the CAN bus stops working. In that case the BMS will manage it

All inputs highly appreciated

Suggest you open a new thread... You need a lot guidance.
Well a wise decision to just buy everything and then ask for advice.....
You have here a high current instalation where you need to know what you are doing, thats very dangerous playing with 500A+. There is a reason everything kept below 200A,Victron the only relable brand on the market who has a 5000W inverter in 12V for example. and then moved up to 24V.
No personal offense but the diagram shows me you don't know what you are doing. Having megafuses in the Lynx and then additional class T is completely senseless.
Eg every voltage drop results in additional amps which is stress for the whole equipment, 0.1V drop on 500A means another min 50A additional.
2x500A fuse as main? Do you run 2x200mm2 cable from the cells to the lynx?
How big is your bank, how many C can is do continous. That fuse should be speced for
1) to protect the cable, see rating charts
2)limit the current (can bank deliver 1000A?) to the max continous current of your bank+install and matched to the interrupt current rating of the fuse which must be equal till smaller then cable rating of 1). Assume you wanna limit to 500A,so you need 2x250A class T here. Also half the voltage drop then...
3) disconnect the bank when a desaster happens and it needs to be rated according to she total short curcuit amps your bank is able to deliver (class T is ok for that)

Everything has to be controlled on cell level by the REC BMS and not by Cerbo or BMV.
I don't know the REC BMS in that detail, so i leave it to the ones they do how all has to be connected.

Not aware the Lynx shunt can be used with REC BMS,if so neat combo allowing to use it with DIY cells banks and not just Victron batteries.

[CatNewBee]

Originally Posted by SFH

Going back to the initial topic for this thread.



I have adapted CatNewBee/SY Destiny baseline design to our Jeanneau 53. Relays are ML-RBS and the interface is the same as CatNewBee.



The only difference is that I have include a Victron Lynx power/Shunt/Distributor bar



The Lynx Shunt is on the CAN bus while the BMV shunt is basically only to control the legacy charge relay



I would appreciate any comments or inputs before I cut the cables and start connecting. Please see attachment



Thanks

Steen

I see 2 issues, the shore chargers (are they configurable to LFP flat profiles?) I rated them as legacy charge sources too and connected them to the alternator side of the ML-RBS, between alternator and solenoid are the charge distribution blocks, they have 2 tasks, always charge the start battery and have always a battery as dump load connected to the alternator. This protects the alternators when disconnecting them under load.

Second issue BMV shunt, id is dual-use for the BMV AND the REC, the REC needs a shunt to work. The CAN shunt is obsolete, you can connect the BMV via VeDirect to the cerbo, no need for the Lynx at all, too far away from the battery anyway.


Temp sensors at the battery from chargers are dangerous BS, don't install them, the only sensors go to the BMS. Chargers should never adapt the voltage based on temperature for LFP, so this sensors have to go.

You use LYNX busbars with fuses, other fuses are most likely obsolete then.

The Color Control remote is obsolete if you intent to use the cerbo, you can switch and change the limits on the touch screen. If you connect the color control, you loose the touch capability for this probably.

[CatNewBee]

Custom integration of the Mastervolt inverter into the system, reporting DC Amp draw, visualising the flows...

[CaptainRivet]

Originally Posted by CatNewBee

So news from our system, first time had an cell out of balance alarm and charger disconnect event in 4 years.

Last time I balanced it 1 year ago.

We had not charged full for over 40 days, PSOC use between 40 and 80..90% SOC, all looked well - until we charged full. The balancers were not able to get the bank in a safe balanced state almost 0.3V voltage difference to the lowest cell.

Will have to charge more frequently to 3.650V full in the future. May add additional balancers.

Now I balance the cells manually with ceramic resistors (5A), takes a couple of hours to get the cells to the same level.

So think twice if stopping charging earlier is a good thing or a bad thing.

Just saw this.
You are sure thats the issue?
Active or passive balancing?
At voltage level did you stop charging daily, 3,55V?
It depends how and when balancing starts with the REC, if done from 3,45 volt on and you go to 3,55 then it might not be enough time but if it done from 3,30V or continous then it should be.
There is a ongoing discussion if a active balance can work properly and eg Dacian, the developer of the electrodacus BMS states it cannot and thats why he implemented a passive one.
If thats right I have not enough experience about that to judge, still learning here....

Interesting article from Eric Bertscher from Nordkyn design when terminating the charge:
https://nordkyndesign.com/charging-m...battery-banks/

[CatNewBee]

Originally Posted by CaptainRivet

Just saw this.

You are sure thats the issue?

Active or passive balancing?

At voltage level did you stop charging daily, 3,55V?

It depends how and when balancing starts with the REC, if done from 3,45 volt on and you go to 3,55 then it might not be enough time but if it done from 3,30V or continous then it should be.

There is a ongoing discussion if a active balance can work properly and eg Dacian, the developer of the electrodacus BMS states it cannot and thats why he implemented a passive one.

If thats right I have not enough experience about that to judge, still learning here....

That is how the cells and balancers behave in the real world. Just observations and mitigation, also a reason why proper balancing and full charging is necessary.

[CaptainRivet]

Originally Posted by CatNewBee

Custom integration of the Mastervolt inverter into the system, reporting DC Amp draw, visualising the flows...Attachment 257741

Rocks
Ok i have to look into venus OX on a raspberry pi too what you can do here is ace.

[CaptainRivet]

Originally Posted by CatNewBee

That is how the cells and balancers behave in the real world. Just observations and mitigation, also a reason why proper balancing and full charging is necessary.

If you read Eric's article the real question is when is LifePo4 really full. His answer is depends when termination current is reached but not fixed at 3,65V. Suggest to read it, very interesting. Can you set in she REC that all 14 days it should charge to 3,65V, otherwise 3,55V?
Requested to Darcian to make this configurable in Electrodacus but he stated daily to 3,5 or 3,55V is full and fine for balancing

[CaptainRivet]

Due to Eric its a combination of voltage and current:
Part of the article:
anufacturer-specified termination condition 3.65V @ 0.033C 3.65V @ 0.05C

Cell voltage (V) Termination current (C) Termination current (C)
3.370 0.000 0.000
3.400 0.004 0.005
3.425 0.006 0.010
3.450 0.009 0.014
3.475 0.012 0.019
3.500 0.015 0.023
3.525 0.018 0.028
3.550 0.021 0.032
3.575 0.024 0.037
3.600 0.027 0.041
3.625 0.030 0.046
3.650 0.033 0.050


Example:

Charging an older generation cell up to 3.500V, we need to terminate the charge when the current is at most 0.015C. When there is no guarantee that the charge current will be at least as high as the termination current at the chosen absorption voltage, adaptive termination still works: if we were charging the same cell with solar power on a dull day and the current was only 0.012C, the above table shows that the termination condition should be deemed to be hit when the cell voltage reaches 3.475V

[Catapulte]

Originally Posted by CatNewBee

Custom integration of the Mastervolt inverter into the system, reporting DC Amp draw, visualising the flows...Attachment 257741

CatNewBee....


Would it be possible to show the integration of the Mastervolt inverter on the original Cerbo GX Touchscreen when running your software ?
Or asked the other way ... Could your software be run in the original Cerbo GX instead of the original software from Victron Energy or is this only possible when it runs on the Raspberry Pi ?


BTW: Thank you for the great work you are doing here and all the inspiration.