diy solar

diy solar

Switching my house bank to Lifepo4 & Adding Inverter with Generator.

OceanStateTuning

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So I am still buying the parts for this, I have an older boat, 1997 Mainship 34 Motor Yacht. It currently had a Kohler 6500 Watt Genny and Twin 454 EFI engines. This year we will be keeping it on my mooring and will only see dock side on certain trips. Generally when I go somewhere we will be on the hook.

Here is my plan, feel free to give your .02 as I am now to LifePo4 setups and battery solar.

Minimum of 2 Solar panels - Either Solarworld 245 or Trina 305 (I have a few dozen left over from my Craigslist hoarding buys) How I want to mount them the Trina would be easier over my Bimini, Solar world on my hardtop (We also use that for storage) As soon as it is a less cold/windy out I will play with this more. MPPT will probably be a 100/50 Victron

Lishen 272AH 4S 12V setup (Have, bought locally from an eBay seller 1/25/21) Will do all the balancing prior to install once I settle on my "fixture"

Victron Multiplus 2000 12v 120v, 160A max input (On order, should see today)

Victron Orion 12/12-18, Have not ordered yet, not stuck on this but does make sense for when traveling at night to have some charging to the house bank.

I plan to essentially splice in my Multiplus in between the Genny and the transfer switch from shore power. I will wire the virtual switch to auto start the genny when the voltage drops to low and the Multiplus can top off the batteries. With what I plan to have for a load, I will have more then enough power for 1 full day on batteries and almost 2 days. Generally most nights will be a single night out for us anyway but again the Genny will auto start or if I know I will be using a lot of power I can hit the Genny switch anyway. I would LOVE to control the Genny with a GX but can't justify the cost right now. I need to isolate my alternators to just my starting bank, and I will have Orion charge my House bank from that.

I have not bought a BMS yet, Daly seems to be the go to? My house bank is on a 50A breaker, Multiplus says max of 160A. I would think anything above 210A will make sure I should never have an issue do to under sizing, that being said a 250A Daly BT unit seems to be my best bet. Please give me input here.

What do you guys think of my plan? Just hoping to have everything be able to work as simple as possible where if the wife goes to the boat without me, no thoughts really need to be made. Fridge will always be switched on so drinks will be kept cool. I have the remote switch for the Victron, I may keep that off while I am not at the boat making it the only switch that needs to be touched to get out 120v, though most everything is 12v.
 
Victron Orion 12/12-18
I assume you are talking about the Orion TR Smart. (The strait Orion is not a charger... it is just a DC-DC converter)

I plan to essentially splice in my Multiplus in between the Genny and the transfer switch from shore power.
Is this what you mean?
1611603614041.png

I would be tempted to do this (particularly if it is an automatic xfer switch.)
1611603694853.png

This would allow you to charge from either the shore power or the generator. I know it will not be at dock often, but when it is......

I believe some of the other Victron inverter-chargers have two AC inputs. If you get one of those it could look like this:
1611604176637.png
However you do it, pay close attention to the Ground-Neutral bond in the system.
  • There should only be one G-N bond at any given time.
  • When on shore power, the Shore power monument has the G-N bond and there should not be one on the boat system.
  • When on Generator, The generator should have the G-N bond
  • When on the inverter, the Multiplus will turn on a relay to provide the G-N bond.
 
Yes to Orion TR Smart, Everything Bluetooth if possible.

Yes the top one, this will allow me to use most of my existing wiring/switches without any issue. Ideally I would go with a Quattro unit but they are almost double the price. To do the middle option you suggested would require adding about two 15' strings of wiring due to the location of my switches (manual not automatic) are far from where a multiplus could be mounted.

Mainship Switches.jpg

On the grounding, Basically I have a 6/3 wire coming from my Generator in the engine room (Multiplus would go inline with this, obviously with a new 6/3 on one of the sides as it would be a hair short ) Goes to a manual transfer switch (and then to a parallel switch as I have 2 30amp cords, everything is 120v). I do not think there is any manual switch to shut off the ground or natural wire when switching from shore to generator. I will double check on this next weekend when I go to the boat.
 
In the picture it looks like there are two different switch-pairs with lock-outs. Can you explain what they are for?
 
In the picture it looks like there are two different switch-pairs with lock-outs. Can you explain what they are for?


2 shore power connections on the boat, twin 30 amp plugs. Left side is shore power plug 1, right is plug 2, if using only 1 30amp plug then you run Shore 1 normal and flip the second switch on shore power 2 to parallel. If running both 30 amp plugs, put them both on shore power. If running generator then put the first one to generator and put the second one to parallel.... makes going any other route much complicated if i don't want to redo everything. Did I explain that to make sense? lol Under shore power 1, that 30Amp plug powers all the breakers under it and wont power anything under Shore 2, Shore 2 either needs to be plugged in OR the parallel switch must be on.
 

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Got it.... Rather complex but effective if you have large AC loads and need two shore power plugs. If on two plugs, I assume each plug drives a different set of appliances. I can see why you don't want to mess with it.

It looks like both Hot and Neutral are switched. That is good.
I do not think there is any manual switch to shut off the ground or natural wire when switching from shore to generator.
It looks like the system was well designed, so here is what is most likely set up.
  • When the switches are set to shore power, the Neutral from the generator is out of the circuit so the rest of the system does not see the N-G bond from the generator. However, when the switches are on shore power, the neutral from shore power is switched in. Shore power always has a N-G bond so the system does see the bond from the shore power.
  • When the switches are set to Generator power, Shore power neutral is out of the circuit so the rest of the system does not see the N-G bond from shore. However, The generator has a Neutral-Ground bond and the generator neutral will be switched in so the rest of the system will see the N-G bond of the generator.
  • When you put the Multi-plus in, it will provide the N-G bond when on inverter but use the generator N-G bond when on battery.
  • The ground circuit is never switched.
Bottom line.... I think it will work without any special tricks.

I am curious: do the shore circuits have isolation transformers or Galvanic isolators?
 
Got it.... Rather complex but effective if you have large AC loads and need two shore power plugs. If on two plugs, I assume each plug drives a different set of appliances. I can see why you don't want to mess with it.

We never need both plugs since really only need for both is if using both A/C systems, to be honest we hardly ever use A/C BUT since it is reverse cycle, it does get used for heat on occasion in the fall. But yeah like you said it is pretty complex but works well so be a pita to do anything else.

I am curious: do the shore circuits have isolation transformers or Galvanic isolators?

Right behind the panel it has what is called a "Zinc Saver" tied into I believe the grounding system.


Great news on everything else! These systems sure get your brain turning lol
 
Yup. A 'Zinc Saver' is a galvanic isolator. It is a a power diode that sits in series on the Shore-Power Ground line and provides a couple volts differential between ship ground and shore ground. This voltage is enough to minimize galvanic action on the ship's metal.

One word of caution. Galvanic Isolators can go bad with an open circuit.... and there is no obvious indication it has happened. This can leave your system ungrounded and dangerous. Consequently you want to check them occasionally.

Some newer Galvanic Isolators claim to be fail safe and fail as a closed circuit. This leaves the boat grounded but without the galvanic isolation.
 
One word of caution. Galvanic Isolators can go bad with an open circuit.... and there is no obvious indication it has happened. This can leave your system ungrounded and dangerous. Consequently you want to check them occasionally.
Good advice, I'll it next time I am there!
 
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