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

[dooleedooroo]

CNB, questions about the solar charging. I see you are using one MPPT for all the panels, what is your opinion on using one MPPT for each panel compare to your setup.

Also about the OVP for solar charging, I see you put the relay between the MPPT and battery. In OV disconnect situation, will this damage the panel? I see that victron MPPT has "Automatic load disconnect" function at 14V. Is this function enough for OVP?

[CatNewBee]

Originally Posted by dooleedooroo

CNB, questions about the solar charging. I see you are using one MPPT for all the panels, what is your opinion on using one MPPT for each panel compare to your setup.

Also about the OVP for solar charging, I see you put the relay between the MPPT and battery. In OV disconnect situation, will this damage the panel? I see that victron MPPT has "Automatic load disconnect" function at 14V. Is this function enough for OVP?

I am redesigning this over the winter, will use a separate contact to disable the MPPT controller by the remote switch input instead of the solenoid. The panels are safe, but the controller may not like it. Generally there is never a OVP event in normal operations, except you misconfigure a charge source on purpose, the Absorptions settings as way deeper than the shut off voltage of a single cell running out of balance, it never happened yet, except while testing the BMS (I set the switch-off voltage to a deeper value to trigger a disconnect without overcharging a cell on purpose) . I intent to use the signal of the opto-coupler to turn off the solar way before the solenoid kills the bus. Not sure if I stop charge or force float at this point.

Anyway, it is easy to add a small reed contact relay on the interface to have another potential-free contact available, there are DIL relay with two independent contacts if you have 2 solar controllers. Always use separate contacts per controller!

[YARGESOL]

Good morning, CatNewBee! Two questions regarding your setup:
- the electrical schema,whicn you've posted on the page 1 showes load distribution "Induction cook top - Fase 1 / Induction cook top - Fase 2". How do you get 2 fases with 220V ?
- on the page 4 you've posted the control plan for charging and loads - it showes "Interface". Is it BMS/BMV interface , or it's custom/DIY interface ?
Thanks for sharing

[CatNewBee]

I am not sure, what you are referring to, but it is a single phase 220V system, each high current device has its own cable to the main distribution with a dedicated automatic fuse.

The induction hob can be configured either to 2 phase 220V (the 3rd phase goes then to the oven) or to single phase by a bridge. But this is specific to the model. I use single phase for everything on board.

EDIT: found it, this was the original plan, where the bridging of the phases was at the fuse distribution panel, but finally I used a 3 wires 6mm2 and a single fuse with the bridge at the hob.

Regarding the interface, it is my DIY interface explained in detail with circuit diagram in the post. The BMS has galvanically isolated C/NC/NO relays and Opto-coupler outputs, the signals are static, means if a channel is on there is a permanent signal. In order to use bi-stable relays (ML-RBS) at extreme low power draft you need SET or RESET Impulses, that is what the interface does, it also shows the states of all BMS outputs by LED and protects them from over-current. You could contact the solenoids directly, but then they will draw permanently 200..300mA each when you have permanent signals on the input.

[Steve_C]

Originally Posted by CatNewBee

No, look at the drawing, it is a short pulse of 50ms created by the capacitor in line with the input. When powered on, the capacitor pulls up the input and than no current is flowing when it is charged, so the input is then low again.

When the signal goes down, the capacitor discharges quickly over the resistor and the LED to accept the next signal if necessary.

It is a 100 microfarrad capacitor, discharging takes about 500ms. Without the Resistor and the LED it would take a minute or longer until the capacitor looses enough charge and can pull up the input on a subsequent high.

You can test it easily with a 12v power supply, connect red and ground and attach a capacitor one side to plus and the other to the R (brown) respectively S (orange) contact, the relay will flip once, but as long as the capacitor is charged, you cannot repeat the switching. Short the capacitor and try again, it will switch again.

So the whole logic is a capacitor and a resistor for discharge, the LED is a bonus to have a free feed back on the current input state.

You loose 10mA per resistor and glowing LED when running, so my interface draws 50mA continous, not a problem with solar and 1000Ah.

If you connect a static signal, the ML-RBS draws around 10 times more energy - approximately 100...120mA.

Hi CatNewBee,

Could you please post a clear picture of your implementation of this detail please? I am going to replicate this and am not exactly sure how to either mount or package this. I also want want to make sure I very clearly understand how you have it wired so I don't make any mistakes. My Blue Sea ML-RBS will be here next week and I want to test everything out in the workshop.

Thanks again for all your efforts!

[CatNewBee]

Originally Posted by Steve_C

Hi CatNewBee,

Could you please post a clear picture of your implementation of this detail please? I am going to replicate this and am not exactly sure how to either mount or package this. I also want want to make sure I very clearly understand how you have it wired so I don't make any mistakes. My Blue Sea ML-RBS will be here next week and I want to test everything out in the workshop.

Thanks again for all your efforts!

I hope, this helps...

[YARGESOL]

CNB, you have chosen REC BMC with display,temperature sensor and CAN cable. Was it actually needed ? Or, it's just "better to have" ?
They - REC,Slovenia - do not answer phone, neither email. One dealer in Germany - https://www.nothnagel-marine.de/ seems to have on stock. But,chosing the cheepest REC-ABMS-4S Active BMS for 299 euros , the site "reccomend the following product REC-ABMS CONTROL SOFTWARE INCL/
RS-485 CABLE" ,for 149 euros
What is the actual spec for BMS you may reccomend ?

[Steve_C]

Originally Posted by CatNewBee

I hope, this helps... Attachment 207483Attachment 207484

Actually I understand the schematics, and they are quite clear and helpful. What I was wondering was how you actually implemented. Did you mount all of these on one circuit board? individually? I am just trying to decide how I want to actually build them.

Thanks!

[CatNewBee]

Originally Posted by Steve_C

Actually I understand the schematics, and they are quite clear and helpful. What I was wondering was how you actually implemented. Did you mount all of these on one circuit board? individually? I am just trying to decide how I want to actually build them.

Thanks!

I used an universal prototype board, and a IP67 case with clear lid to see the status, nothing special. You can of course produce a nice printed circuit board, but for this few items it was not worth the effort. I put it in a large case simply to ease the access to all the wires (10 from the BMS, 2 power supply, 20 for the solenoids, 3 from the BMV, 4 to the Quattro).

[Steve_C]

Originally Posted by CatNewBee

I used an universal prototype board, and a IP67 case with clear lid to see the status, nothing special. You can of course produce a nice printed circuit board, but for this few items it was not worth the effort. I put it in a large case simply to ease the access to all the wires (10 from the BMS, 2 power supply, 20 for the solenoids, 3 from the BMV, 4 to the Quattro). Attachment 207511Attachment 207512

Great, that's exactly what I was looking for. The number of wires coming in really does add up quickly.

Thanks again!

[Bob James]

I noticed a distinct lack of actual photos?
Just drawings .

You say you have installed these but where are the pictures of it . One picture saves a thousand words you know.


I saw a couple of an interface . Are there photos of the rest somewhere please?

[CatNewBee]

Originally Posted by Bob James

I noticed a distinct lack of actual photos?
Just drawings .

You say you have installed these but where are the pictures of it . One picture saves a thousand words you know.


I saw a couple of an interface . Are there photos of the rest somewhere please?

View under the guest bed, batteries below, up is the board with the power control logic, positive side starting with power bar and main fuses on the left, then solenoids and distribution fuses, 2x96mm2 to the Quattro, then legacy manual clutches on the bottom, on the top right the negative bar to the shunt and from there to the negative clutch / 2 wires to the Quattro behind the wall, below the bms on the right and the interface box in the middle, on the far right (not visible here is the Victron MPPT controller.

Above all this is a board (removed for the picture) giving protection to the circuit and allowing for some storage, closing the gap with the factory installed drawer.

[arsenelupiga]

Hi cnb, just to say hi before CF police throws me out accusing me of still owning lagoon.

I have done 1 year 400 AH LI battery service. I only use solar MPPT's to charge and have disconnected alternators charging home battery. Also added electric outboard that charges from house battery and moved anchor winch onto house batteries as well. Very simple but effective setup.

Planned to add switch to be able to turn on alternator charging house batteries but I do not see that needed any longer. My 360 W solar does all the work 365 days a year. Amazing how much more power we have on board by just changing to lithium for additional 2 k AUD investment.

We had couple overniters and it was amazing feeling not having to turn on engines to charge.

thanks and have nice sailing

[hzcruiser]

Originally Posted by arsenelupiga

Hi cnb, just to say hi before CF police throws me out accusing me of still owning lagoon.

Has that happened before?

[...]

Planned to add switch to be able to turn on alternator charging house batteries but I do not see that needed any longer. My 360 W solar does all the work 365 days a year. Amazing how much more power we have on board by just changing to lithium for additional 2 k AUD investment.

We had couple overniters and it was amazing feeling not having to turn on engines to charge.

Good to know, thanks! 360 W might not be enough for a live aboard but could be plenty for the weeekend warrior.

[arsenelupiga]

Originally Posted by hzcruiser

Has that happened before?






Good to know, thanks! 360 W might not be enough for a live aboard but could be plenty for the weeekend warrior.

yeah, lagoon negative sentiment is widespread in CF. Dont ask me why, it is an excellent boat.

We are actually liveaboards and live off 360W. Probably fiji this year. Our boat is lighter than average lagoon and therefore sails better. Should not say more as may offend some peoples feelings here.