Hybrid system using new Sterling Power B2B chargers

[rgleason]

Originally Posted by cuffy

Deividas
..spending the summer on anchor. Sterling B2B 60a, 80% efficient, not good for solar charging. ..Epever Solar controller w/custom settings is now direct to LFP
..123 bms is OK, I love the app and the readings ..have a 0.2v difference between the boards, well 1 reading low ... not good for top balancing on the go. ..also use their relay, 120a, which does everything it says.
.. 400w solar very little shading, ..fridge, freezer and hot water, only using the Honda for about 8hrs this year.

Cuffy, thanks.

Stirling B2B, How do you know it is 80% efficient? Specs? Measurement?
Is there much heat at high output?
I am very interested in your experience with 123BMS.
Do you have a single relay setup?
Is that 0.2v difference from a bad cell possibly? Have you measured with an accurate meter?


Smacc999 likes his master volt mac plus 122/12/ 50 "is rated 97% peak eff. (95% worst) It has no heat sinks or fan. I had like 50a in and 49a out"
Specs say: > 95 % (at nom. input voltage, full load); peak 97 %
10.0 x 6.5 x 2.6 inch $450-$600 (If I can do without this cost, it would be very helpful.) -- Veldman's System

[cuffy]

Originally Posted by rgleason

Cuffy, thanks.

Stirling B2B, How do you know it is 80% efficient? Specs? Measurement?
Is there much heat at high output?
I am very interested in your experience with 123BMS.
Do you have a single relay setup?
Is that 0.2v difference from a bad cell possibly? Have you measured with an accurate meter?


Smacc999 likes his master volt mac plus 122/12/ 50 "is rated 97% peak eff. (95% worst) It has no heat sinks or fan. I had like 50a in and 49a out"
Specs say: > 95 % (at nom. input voltage, full load); peak 97 %
10.0 x 6.5 x 2.6 inch $450-$600 (If I can do without this cost, it would be very helpful.) -- Veldman's System

The 80% comes from solar input minus reading at shunt, which at best is half rated power of B2B. Haven't took much notice when motoring but Smacc figures sound about right.

I top balanced the bank last winter and both my meters showed that all V were equal. As soon as I reassembled the bms showed .2 difference. After a couple of weeks I swapped cells about and still got same board reading low.

Will now look into Mastervolt unit

Cuffy

[Pete7]

Sadly, Mastervolt are not very popular in the UK and always very expensive. Looks like 3x the price of a Sterling DC.DC charger.

However, Victron offer a 12v 30A DC>DC charger at 1.5x of the Sterling. Just noticed it has a remote on off switch option, controlled by a BMS perhaps? Victron claim a 87% efficiency

https://www.victronenergy.com/upload...60-400W-EN.pdf

Pete

[Deividas]

I found more detailed Victron schematic. In general the same idea as mine.

[rgleason]

Originally Posted by Deividas

I found more detailed Victron schematic. In general the same idea as mine.

That's a good schematic, but I'd rather charge the 200ah LFP batteries at greater than the 30a allowed with the Orion 12/12-30a. Victron recommends 50a charge current for each 100ah battery, so theoretically you can charge 200ah at 100a.

Provided the Alternator (100a hot continous output) has proper external regulation for LFP why can't the cost of the Orion DCDC be eliminated and the BMS and Battery Protect be used directly?

For greater over charge protection perhaps the Alarm control wiring with a relay could be used to disconnect either the Alternator field wire or the brown switch wire (only used for emergencies to totally disconnect the alt, according the S/V Jedi)

[Pete7]

Good question, you can stack the Victrons to increase the charging current, but that gets expensive.

Equally installing an alternator capable of sustained 100A probably means twin belts or a serpentine belt and an external regulator. For me it would be cheaper to stack a pair of Victrons for 60A and still have enough to buy a third before the costs reach a Balmar and external regulator package.

This would defeat the desire for a simple relatively cheap installation for me. Also I would prefer to use solar to charge the LFP, either directly from the MPPT or via the engine start battery and Orion. Prices of new large solar panels in the UK are now 30p a watt. Used good condition are even cheaper.

Deividas, great diagram, but can't help think that the only thing it is doing is creating profits for Victrons share holders. Are there any products they haven't included in that diagram

[rgleason]

Originally Posted by Pete7

Good question, you can stack the Victrons to increase the charging current, but that gets expensive.

Pete, I get your point about using Solar, that's a great price, looks like it is wrapped as a present for the New Year.

I am going to do Evm1024's Delco Remy 28SI 12v 160a #8600312 conversion to external regulation and hopefully get two J10 pulleys machined to pull the alternator forward just 1.5" on the engine. It will be more expensive than one Orion for sure + time.

There are many ways to do this. Is there any experience using Orion which would shed light on efficiency (victron docs have 87%) and heat generation?

[Deividas]

Originally Posted by rgleason

That's a good schematic, but I'd rather charge the 200ah LFP batteries at greater than the 30a allowed with the Orion 12/12-30a. Victron recommends 50a charge current for each 100ah battery, so theoretically you can charge 200ah at 100a.

I don't think that there is a reason to increase shore charging up to the limit. The boat is not a car and I don't need fast charging. Most often I will stay at the marina for a night at least. So there is no reason if I will have 30 or 100 Amps.

Another question is solar or alternator.

[rgleason]

Originally Posted by Deividas

I don't think that there is a reason to increase shore charging up to the limit. The boat is not a car and I don't need fast charging. Most often I will stay at the marina for a night at least. So there is no reason if I will have 30 or 100 Amps.

Another question is solar or alternator.

Delvidas:
Everyone is different with different requirements. Our system is not an appropriate response if you reside in a slip.

We are on a mooring and Never use a slip. While cruising I want to charge up during the 3/4-2hr per day (80a-90a) that we are going in and out of harbors, and charging up our Eutectic Refrigerator (7a), if possible. While at sea we use more power (135a-140a) and will use the alternator intermittently as needed for that. Our priorities are: New big case 160a Alt de-rated to 100a, Solar, then LFP or FF.

The boat has limited room for solar, perhaps (2) 100w max on the stern on adjustable angle & tilt twin posts.