Charging setup for Scimitar

[Qlder1]

I am just about to dive into the deeper end of boating (for me anyway) by buying a Scimitar 1010. It has a relatively outdated electrical system and I want to upgrade to a more modern setup. I plan to install 680AH lithium house bank , 540W solar panel w- 40A solar controller, 2 x 40A dc/dc chargers (one on each 120A alternator), as well as a 3kw inverter. Now as an electrician (well non practicing for @ 20yrs ) I think I can handle the install and circuit protection etc, but I would like confirmation from someone a bit more marine savvy that having 3 simultaneous charging systems into 1 big lithium house battery is a workable solution. Also I would have N70 lead acid start batteries charging from each alternator as well . I have been researching the items required and either Victron or Renogy seem pretty well regarded. Any help would be greatly appreciated.

[Alchemy]

Congrats on the upgrade! I took the plunge last year and bought a 10.4m Jarkan power cat. The Scimitar is a much nicer boat than mine though. I don’t see any issue with what you’re proposing, and I have started what you are looking to do. I have installed 4 x 200ah lithiums, and two x 40amp dcdc chargers. My dcdc can take solar input, but I only have a Bimini over the fly bridge so can’t install solar easily, yet. I too will be looking at a 3000w inverter. Perhaps the Victron multi plus 2, but not sure on that choice yet. It might be easier to have seperate inverter and seperate charger for the lithium bank. My engines only have 80amp alternators, so at some point will look to upgrade to 120amp.

I’ll be interested to hear what you end up doing, and if you ever want to swap notes then let me know. The whole moored boat thing has been a steep learning curve for me, after being in trailer boats most of my life.

regards,
dave.

PS, there is a Scimitar owners group on f book which I follow, as there is no info out there on my make of boat. You might find good info there too.
PPS, there is also a u tube channel called “motor sailing for old dudes”. He has documented a lithium upgrade similar to what you want, so that is worth a look.

[Qlder1]

Thks Dave for the reply. Yeah definitely whole new world, just the insurance and marina stuff is pretty daunting to start with, especially in northern Aus. How was your experience with that? At least you appear to have had a larger trailer boat previously. Biggest I've owned was 6.5m, and a few of these companies flat out refuse insurance for lack of experience on bigger boats, as well as cyclone risk north of Gladstone....

I found the FB group a few weeks ago, very helpful already. I have contacted another guy here in Rocky that's just bought one, made me feel better about spending well over $300k on a 20yr old boat that is effectively a "fixer upper" haha

Alternators are something I am worried about, even 120A ones probably won't like being loaded up while at idle speeds, not sure if it might require vsr's to stop excessive current draw from the DC/DC chargers or not.

[Corry]

Sorry, I can't help with answering any questions, just wanted to say that I am envious of the boats that you both have, I'd love something like them. We did look at getting a moored boat when we moved to Cairns last year, but as you said, when we started looking into it it was a daunting experience, so are back to looking at trailer boats again.
Congrats on your purchase, I'm guessing you'll be based out of Roslyn Bay, great part of the coast to have something like this.

[Alchemy]

I’d had some experience on larger boats, all be it quite a while ago so found the insurance relatively easy. I went with club marine, who I had about 20 years insurance with for my 3 previous trailer boats. Marinas down here were fairly straight forward too. My beam is only 4.6m, so I am on a 13m mono berth which saves me a bit versus a dedicated multi hull berth. I’ve also managed to get a pen, which is great as I don’t have to worry about bumping into a boat beside me.

Re the cyclone risk, Club Marine charge a 10% excess if you make a claim due to a named cyclone. I’ve been researching berth options in Townsville as I hope to move back in the next few years and the prices are higher than SQ, and availability lower. I am considering buying a lease but need to understand what happens when the master lease expires, and what costs are involved in keeping the berth.

Re alternators, Balmar make a range of high output alternators, but they’re not cheap. My dcdc chargers only take a charge once the start batteries are at a certain voltage, but can’t recall what that voltage is.

My boat is in the fixer upper category too, but I paid about half of what you have so I don’t mind pouring some money into it. You live in a great part of the world for cruising, and I can’t wait till I have the time to explore up your way and beyond.

[disorderly]

Like Corry I am also a bit envious of you guys having boats which you can spend some time on with comfort at sea.....Your 10m cats would be just totally amazing to explore the reefs and islands up here....Though I do like having a trailer boat which gets backed into the shed and forgotton about till next trip...

Like the poor buggaa's at the former 250 berth Port Hinchinbrook marina, design might also be a consideration when choosing a place to berth in the Tropics.....During Cyclone Yasi it became apparent that the pylon height was too low and the pontoons floated over the top during the storm surge and were pounded onto the shore in an ugly mess..many of the owners were not impressed and some pretty devestated.....there were also some blokes that moved their boats out of the marina into small creeks and tied up against the mangroves that suffered minimal damage...

Hinchi marina.jpg

I ran into a fella from Brisbane at the ramp the other day that had just bought a Blackwatch 26 (LOA about 30 foot) from Cairns...Him, his missus, son and dog were all aboard and were planning to spend some months liesurely motoring down the coast ...Hinchinbrook region was next on the list for them and at least you can find some anchorages there out of the Tradewinds...it has been one of the worst years ever for boating up in FNQ...

Looking forward to hearing more from you guys about the life and times of a big boat owner..

How are the kids enjoying the new boat Dave....or are you spending more time working on it then using it at the moment..?

[Lovey80]

Alternators are something I am worried about, even 120A ones probably won't like being loaded up while at idle speeds, not sure if it might require vsr's to stop excessive current draw from the DC/DC chargers or not.

I wouldn’t be too worried about the alternators if you are running quality dc-dc chargers. All the good ones either run a voltage sense wire to the lead acid or have an automatic part in their charge profile that stops them charging every 3 minutes to do a start battery test before resuming.

I’ll be doing something similar on my next boat build that will have 2x300Ah banks, though less solar input. I’m thinking the RedArc 50Amp DCDC is at the front of the list at the moment. No fans and the whole circuit board is sealed in some sort of epoxy so should be good for a salt water environment. I have the Enerdrive 40+ DCDC in my Ute. It’s not suitable for marine use in any way and while it’s fine for that application. The unit only runs one or the other in terms of solar or alternator. When the Ute starts, it gives it time to hit the right voltage on the start battery before it activates and shuts off the solar.

the RedArc prioritises solar input and runs from the alternator at the same time. If you’re getting say 20amps from the solar input it will only draw 30 from the alternator/lead acid battery. Good if you’re worried about your alternator.

if on the other hand you need maximum charging when you can get it, then running separate devices is the go. That massive lithium bank will have no drama accepting charge from three different sources. As long as you have them all set to the same target charge voltage (say 14.2v) Just make sure you run all of them to a negative bus and have your shunt between the bus and the negative of your battery so you know accurately what’s going in and going out.

[Lovey80]

Oh, forgot to ask. What lithium bank are you planning? Pre made or building it yourself using cells?

[on-one]

I can't answer your question either but have some others. Have you worked through what you're using onboard and how much power you need? My house batteries (agm) and solar panel are half the size and run everything (fridge, lights, tv, toilet, holding tank, water pumps etc etc) on a 33ft boat and it's never needed more. One other consideration is to check your insurer's position on lithium batteries even if you can do the work yourself you may want to have proof of a professional install if there was a fire.

[Qlder1]

I haven't quite worked out which way to go with batteries yet. DCS seem to be well thought of. I also would consider the lower end such as the Giants, maybe worth a shot as I've only heard good things about these, even though they are a lot less money. It seems that build yourself batteries can be cost effective so I might look into that as well. Its got 600ah of n200 lead acids in there atm , they are new so no rush I guess.

The reason for biggish system is I plan to do extended trips and not wanting to fire up engines just to charge and get hot water ect. (it has a 1800W hot water system), and I want to be able to cook stuff with proper gear haha. Even with 600 lithium I will be saving @70-80kg . For chargers I was thinking Victron for dc/dc chargers, and maybe the renogy elite solar controller (quite cheap but also good reports), Solar panel a single JA Solar 540W (only weighs 28.5kg)
Inverter???? no idea need to research them more.

I have heaps of work to do on it before I get to this stuff I suppose , maybe more studying and plans will completely change.

[NAGG]

I know jack about these kind of boats - awesome stuff that you are able to to get into this market

Ultimately though you will need some kind of power generation - a 2KA+ generator .

once away from shore power - you'll need something beyond solar

A combination of 720 watts of Solar & a generator of 2000kw should do the job when off grid


Chris

[disorderly]

The reason for biggish system is I plan to do extended trips and not wanting to fire up engines just to charge and get hot water ect. (it has a 1800W hot water system), and I want to be able to cook stuff with proper gear haha. Solar panel a single JA Solar 540W (only weighs 28.5kg)
.

Any reason you wouldnt use gas for Hot water and cooking...?

500 watts of solar isnt going int going to provide that much charge, particularly if you get some cloud ..

It also depends how many people you are providing for but Chris's advice is good...a 2-3kw gennie would be a must for extended trips...

[Alchemy]

Like Corry I am also a bit envious of you guys having boats which you can spend some time on with comfort at sea.....Your 10m cats would be just totally amazing to explore the reefs and islands up here....Though I do like having a trailer boat which gets backed into the shed and forgotton about till next trip...

Like the poor buggaa's at the former 250 berth Port Hinchinbrook marina, design might also be a consideration when choosing a place to berth in the Tropics.....During Cyclone Yasi it became apparent that the pylon height was too low and the pontoons floated over the top during the storm surge and were pounded onto the shore in an ugly mess..many of the owners were not impressed and some pretty devestated.....there were also some blokes that moved their boats out of the marina into small creeks and tied up against the mangroves that suffered minimal damage...

Hinchi marina.jpg

I ran into a fella from Brisbane at the ramp the other day that had just bought a Blackwatch 26 (LOA about 30 foot) from Cairns...Him, his missus, son and dog were all aboard and were planning to spend some months liesurely motoring down the coast ...Hinchinbrook region was next on the list for them and at least you can find some anchorages there out of the Tradewinds...it has been one of the worst years ever for boating up in FNQ...

Looking forward to hearing more from you guys about the life and times of a big boat owner..

How are the kids enjoying the new boat Dave....or are you spending more time working on it then using it at the moment..?

Hi Scott,

There are lots of advantages to trailer boats, and a big one is the cost of ongoing ownership, and the ability to store out of the weather. The comfort of the big boat is just awesome though. I’ve slowed up on the jobs over the last few months, as I’ve been working on the house but the boat is getting used whenever the weather aligns with a weekend. The kids, Nic and I love it! The dog is still getting used to it. I’ll be slipping it again soon, as soon as I can find someone to fit my new GT51 through hull transducer. I’m also looking to get pricing on a couple of hard tops and some other mods.

I remember the Yasi Cardwell damage well as I was in Townsville at the time. Definitely a concern for moored boat owners in the tropics.

[Alchemy]

I haven't quite worked out which way to go with batteries yet. DCS seem to be well thought of. I also would consider the lower end such as the Giants, maybe worth a shot as I've only heard good things about these, even though they are a lot less money. It seems that build yourself batteries can be cost effective so I might look into that as well. Its got 600ah of n200 lead acids in there atm , they are new so no rush I guess.

The reason for biggish system is I plan to do extended trips and not wanting to fire up engines just to charge and get hot water ect. (it has a 1800W hot water system), and I want to be able to cook stuff with proper gear haha. Even with 600 lithium I will be saving @70-80kg . For chargers I was thinking Victron for dc/dc chargers, and maybe the renogy elite solar controller (quite cheap but also good reports), Solar panel a single JA Solar 540W (only weighs 28.5kg)
Inverter???? no idea need to research them more.

I have heaps of work to do on it before I get to this stuff I suppose , maybe more studying and plans will completely change.

FWIW, I went with itechworld batteries and chargers. My boat only had two start batteries per engine and a dedicated battery for the vhf (survey requirement, but no longer in survey). I’ve cut back to three start batteries, two on one and one on the other engine. I generally use the starboard start system as it has the two start batteries, and keep the port as a back up. My boat was a very basic set up with only one small fridge, so I have gone way over the top for capacity atm. I have already fitted another fridge and might be fitting something like a 200 lite trailblazer as a freezer, one day. I’ve also bought an 80lph desalinator (not yet fitted) which I will run from the inverter, and I am also going to put a 150 litre tuckerbox on board to see how that goes running off the inverter before I invest in more 12 volt refrigeration. Other than that, my cooking is gas, and hot water is via a heat exchanger plumbed to starboard engine. I’ll look at another HWS so I don’t need to run engine for hot water, but will keep current HWS to supplement any new 240v system I install. Probably still way more capacity than I need, but I’d rather have too much.

Club Marine don’t have any restrictions on lithium batteries atm.

Id love to fit a diesel generator too, but they’re expensive and my hulls are quite skinny, so fitting that below decks may be impossible. If I end up living in NQ again, then I will fit a domestic split AC, and will need a genny for that, but may make do with a 2.2kva Honda type.

[Lovey80]

I haven't quite worked out which way to go with batteries yet. DCS seem to be well thought of. I also would consider the lower end such as the Giants, maybe worth a shot as I've only heard good things about these, even though they are a lot less money. It seems that build yourself batteries can be cost effective so I might look into that as well. Its got 600ah of n200 lead acids in there atm , they are new so no rush I guess.

The reason for biggish system is I plan to do extended trips and not wanting to fire up engines just to charge and get hot water ect. (it has a 1800W hot water system), and I want to be able to cook stuff with proper gear haha. Even with 600 lithium I will be saving @70-80kg . For chargers I was thinking Victron for dc/dc chargers, and maybe the renogy elite solar controller (quite cheap but also good reports), Solar panel a single JA Solar 540W (only weighs 28.5kg)
Inverter???? no idea need to research them more.

I have heaps of work to do on it before I get to this stuff I suppose , maybe more studying and plans will completely change.

If you're considering building your own bank out of cells. Eve make really good 304Ah cells that you could put in parallel for 600ah. Also consider that you'll need a BMS that can handle 250A continuous draw to run your 3kw inverter. Also if your style of use means you'll spend really long periods below 100% charge (as in never hitting 100%), it may be handy to grab an active balancer so the times you do get to fully charge the batteries you have a better chance to balance the cells (even the expensive pre-made batteries don't have them). Remember that cell balancing can only occur at the very top of the state of charge (somewhere above 96% or above about 13.8v) PowerPaul Australia also makes custom batteries with active balancers in them for people so look him up on Facebook.

If you're going to go Victron DC-Dc you may as well run victron solar charge controllers as well as a shunt. You can then link them all together with the victron Gx display screen and you can even get it networked so that you can monitor the whole system from home and change settings etc without even going to the boat.

https://www.outbackmarine.com.au/vic...hoC4NkQAvD_BwE