Winter electrical plans, looking for feedback

[luken7]

We have a Beneteau 361 with a Yanmar 3GM30, 27hp engine with the stock Hitachi 60amp alternator. For the battery charger, the stock 20amp charger. We don't have an inverter. For batteries, we have two Trojan T145 and two Energizer EGC2 golf carts, around 440 total amp hours. Also a group 27 starting battery.

We're mostly day sailors and single overnighters, but looking to do two or more nights on the hook routinely this upcoming season.

So here's my thinking, first, upgrading the alternator with a 100amp Balmar and external regulator, or the largest size capable where i dont have to change the pulley and belt type, to help recharging the batteries quicker. Not thinking about replacing the batter charger thinking that if the charger is being used, I'm in a slip overnight.

Also thinking about adding an inverter, and have been reading many threads about pure vs modified. We mainly need it or the tv, microwave and laptops. Most of what I've read talks about modified sine waves not being of good quality anymore and can wreak havoc on electronics over time. So looking at a pure sine wave inverter, around 1500 watts. Also for uniting it, is it safe in the lazarette which is the closest to the battery banks and will have decent ventilation.

Just looking for thoughts and feedback, thanks in advance.
-tony
Sv Hemispheres

 

[Stu Jackson]

That's a pretty robust house bank, and should do you well for more than one night on the hook. Have you done an energy budget? You may not need to upgrade your alternator at all. I ran our boat on five or more day cruises with our OEM 55A alternator for many years, with a smaller house bank (360 ah). Just turned the fridge off at night. You may not have to.

We've been running a modified sine wave inverter since 1998 with our Freedom 15 Inverter/Charger for our microwave and laptop. Works just fine. But since you're in the market for a new one, no reason to not get a pure sine wave one if your budget allows.

I'd do an energy budget first, then add the inverter and only then upgrade to a larger alternator if you feel you must.

 

[Philip_Oceanis 361]

Have you considered ways to reduce consumption first before adding more charging ability?
It really depends what you do (and there's no reason to stop it because it's a leasure yacht) but in my case with only 200amp of service batteries after replacing all G4 halogen bulbs with leds and also changed the 10W anchor light with led (that was a big saving) I need around 40 (max 50) amp every day. The fridge is always on and I have also a 19 inch TV (but no laptop or microwave).
Last year I added a 45W solar panel that under the hot mediterranean sun gives me probably around 15amp every day.
So I always run out of water first when on the hook!

 

[Ron20324]

My battery charger and inverter are in the lazarette of my 323. Should be okay in yours. A shorter cable run is a BIG plus.

 

[Mike B]

If you're only staying out 2-3 days at a time you may not need to upgrade the alternator. I agree with the suggestion to create an energy budget, but even better yet install a Victron battery monitor. A single bank model connected to the house bank should do. It will go a long way in telling you what kind of amp hours you're using. Once you have actual usage info you can determine if you need an bigger alternator or other modification to your set up.

 

[luken7]

Thanks for all the responses. Forgot to mention that I had just replaced all the cabin top lights with LED's also. So we're going to try a battery monitor for now and watch our usage. Thanks Again !!!

 

[luken7]

So a quick update. I'm going to install a Victron battery monitor as I think our usage would be 100 amps per day, worst case. So we're good for two to three days.

Question on the stock Hitachi alternator on the 3GM30F. It's a 60amp alternator. From my understanding, it has an internal regulator that is all or none. Meaning it puts out as much amperage as the batteries can consume, then cuts off when the voltage is detected around 13.5 volts from the batteries. Is that somewhat correct? Also, for the 3GM, I'm able to upgrade to at least an 80amp without changing the pulley or belt type.

Our battery charger is the stock Sentry 20amp smart charger and from my understanding, is a really good charger. Figure that if we're using the battery charger, we're in a slip for a night, at least 10 hours so that should work.

So the only addition for this spring is most likely the Xantrex XM1800 inverter unless we find something else around that price.