Let(39)s talk house batteries for the 45XX-gctid393073

[Woodsong]

Our 45, IMO, has an undersized house battery set up. We have 2 4d batteries- one seems to be for the engines and one for the house battery. We also have a group 24 that seems to be isolated from everything else. For that matter, both the generator and engine battery seem to be separated from the house battery. I have not chased down all the wiring to confirm it but based on voltage levels of everything that appears to be the case. After anchoring out for a few days, it seems our single 4d arrangement for the house battery is no where near adequate. All batteries are basically new- the two 4d's in February, the group 24 generator battery last week. While anchored out the 4d for the house does not seem to last long at all...a few hours at best with just normal usage of lights, head, water pump, etc.

I am curious how other 45 owners have modified their house battery arrangements and how said arrangements have worked out for you. Ideally, I want a battery bank that will allow me to anchor out for an entire day playing on the water, run the generator for 30 minutes or so while cooking dinner, use batteries all night for anchor light, fridge, etc. and run generator for 30 minutes while cooking breakfast and no more than that. I don't want to install a $2k inverter bank at this time as it is cheaper to run the generator for 30 minutes to an hour a day but want a battery set up that will let us anchor out for a few days at a time without constant power management.

In addition to being curious how others have their battery arrangement set up, I am also curious where you may physically be locating your battery bank(s) as there is not much real estate to be had in the engine room! Our 4d's are outboard of the starboard engine- a pain to get to them and all the weight can cause the boat to have a slight list since the 15hp outboard on the dinghy is on that side as well.

[ksanders]

On our boat we run a house bank consisting of four interstate L16HC batteries. This gives us 840 amp hours of capacity.

What we have found is that with normal non conservation mode usage we get about 12 hours out of that system before we reach the 50% mark.

Our boat is addmittidly a power hog. We have the inverter, the KVH SATCOM and lots of other loads. Our link monitor shows actual usage of a low in the mid 20 amp range and up from there. Averaging as I indicated around a 30 amp draw.

Recharging is via a 150 amp charger that I have scaled back to 120 amps max. This means that we have to run the generator approx 3.5 hours twice a day to keep up the house bank on the hook.

From what you are describing, draining a 4D bank in just a few hours you won't ever be in a situation where 30 minbutes of generator time, twice a day will work out. you need to increase your battery bank, and have a charger that will recharge at a pretty high rate in order to minimize generator run time.

[Guest]

I have eight 6v golf cart batteries in two banks, one on port and one on starboard outside of the engines. They are in the standard 8d boxes. While inconveniently located for sure the smaller batteries are manageable. We installed all new Costco batteries after we bought the boat in March 2011. My research indicated that the Costco batteries were equal in construction and quality to the so called "marine" batteries at a fraction of the cost. Certainly, I don't have to chase down Costco for a replacement if one fails or argue with them about how the charging system is working (or not).

I have a box with two 12v batteries in parallel for the engine starting located just aft of the port house batteries and a separate single 12v genset starting battery in a box next to the generator. I can go nearly 3 days using all of the Seaking satellite tv that I want and/or internet netflix/hulu via wireless router. We have to start the genset for hotwater and stove top cooking so that extends the battery time I am sure. I have a Xantrex 3000w inverter that also charges the batteries. We also use the low voltage type electric blankets on the inverter at times when it is less than summer temperatures in the pacific northwest

I serviced all of the batteries after a year on the boat and found that each cell only needed about 3 ounces of distilled water so I am sure that we are not overtaxing the system or some would have been dry. It should be even better now because I just changed out all of the house lights to LEDs. The load should now be a lot less because I shed nearly 800 watts of G4 bulbs. I know that was a big load because the grandkids and guests always like a lot of lights on after sunset when we are on the hook.

[Uncle_Bob]

No matter what configuration of batteries you have you are restricted to what you put in. In other words if you take out 100 amp hours and run the genny long enough to only replenish 99 amp hours, sooner or later you go dry. The standard charger will not replenish your batteries at anchor especially if you increase the bank. They simply do not produce the amperage. The attraction of big inverters is they incorporate big battery chargers. You will need either an inverter or a dedicated improved battery charger to keep your batteries above the recommended 50% discharge. Even with a 100 amp charger you will have to run the generator a minimum 60 minutes a day and more likely 90-120 minutes. You can calculate the battery needs by appraising everything electric you run on 12 volts. The fridge alone could be 100 amps per 24 hours. As far as the best use, and everyone has an opinion, I'd recommend 6 to 8 golf cart batteries. They are 6 volts each so you will need to learn how to hook them up to produce 12 volts. However since you have a 4D already for the house, I would simply add another 4D of the same type and move to golf carts when replacement of the 4D's is required five or so years from now.

[nick4588]

You might also look at the load you are placing on the batteries. Converting the lighting to LED's can save a lot. The standard light fixtures have two 10 watt bulbs each! Also the 45's have several fluorescent fixtures. Those can all be converted to or replaced by LED's. The refrigerator is another big power consumer. We keep cold packs in the freezer and put them in the refer part when we turn the power to the refrigerator off for several hours. So look at demand as well as supply.

A great source for LED's is http://www.superbrightleds.com

Enjoy your boat!

Nick

[cosmo777]

Kevin, and others....

Since getting as many amps as possible back into the house bank is good thing, what about installing an ACR between the generator and the house bank.

With this, its seems that once the generator has topped off its own battery, it can then send amps to the house bank.

So then the house bank would not only be getting charged by the inverter, but also receiving excess amps from the generator alternator.

[mmichellich]

cosmo777 wrote:
Kevin, and others....

Since getting as many amps as possible back into the house bank is good thing, what about installing an ACR between the generator and the house bank.

With this, its seems that once the generator has topped off its own battery, it can then send amps to the house bank.

So then the house bank would not only be getting charged by the inverter, but also receiving excess amps from the generator alternator.

Wouldn't that be kinda like tossing a glass of water on the sidewalk in a thunderstorm and claiming you are helping to wash the sidewalk. Have you looked at the average amps put out by a generator alternator?

[mmichellich]

Your setup has several issues.

First if you only have a stock battery charger it is too small to rapidly bring up a well discharged bank.

Suggest you get a charger that will produce over 100 amp until batteries are almost fully charged.

Your battery bank is darn small. On our 47, we have four 8D deep cycle house/inverter batteries, one 8D start battery and an auto battery for the generator.

One of your Hinos charges the start battery, one the house battery(s), and the gen set charges it's own battery. The engine alternators rapidly reduce their output to less than half the rated output amps a few minutes after startup.

Best solution buy a good inverter charger that charges well over 100 amps. Add lots more batteries, like four 8D or 8 golf cart batteries for your house bank. Never let the charge drop below 50 percent.

Best bang for the buck is still cheap lead acid batteries. Run your own numbers.

[cosmo777]

mmichellich wrote:
Wouldn't that be kinda like tossing a glass of water on the sidewalk in a thunderstorm and claiming you are helping to wash the sidewalk. Have you looked at the average amps put out by a generator alternator?

I dont' think so....If the inverter is pumping say approx 100amps into the house bank (via the generator) and the alternator (assume 50amp) is done charging the generator battery and switches over to charge the house bank with 30amps, that's a 33% increase in charging rate. Or am I missing something here?

[mmichellich]

cosmo777 wrote:
I dont' think so....If the inverter is pumping say approx 100amps into the house bank (via the generator) and the alternator (assume 50amp) is done charging the generator battery and switches over to charge the house bank with 30amps, that's a 33% increase in charging rate. Or am I missing something here?

Don't know the exact alternator on his 45, but on our 47, the Westerbeke alternator is worthless and really hard on batteries. It is speced at 50 amps but hardly puts that out. Once had a dead gen set battery, long story, battery was good just dead. Laid one of those inductive amp meters along side the output and for a minute or so, it would put out a fair amount of current, then dropped to almost zero current, well maybe 5 amps or do. Called Westerbeke and they said the alternator was running normal. They said all that was normally needed was to charge up only that small current lost in one startup. It is hard on batteries as it reaches a terminal voltage over 14 volts. My last gen set was Onan and it boiled batteries also. If one did as you suggest, why would you not effect the chg rate of the battery charger or inverter charger also?

[iceclimber]

I wanted to ask without hopefully not thread jacking; why is running a generator as needed and or desired such a big deal? Seems like an awfully expensive piece of gear to not use. I don't mind the noise all that much...and if I do I simply live without power...and live out of a cooler. Anyway, I don't have the long cruise needs as many do so perhaps the big battery banks are needed. I have decided against the weight and space issues that come with golf cart batteries. To each his own I suppose.

[mmichellich]

I run our gen set for a couple of hours in the morning and a couple again starting about dinner time when anchored. Our stove is electric as well as the microwave. This keeps our batteries fully charged while at anchor. We run two freezers, an ice maker, the refer with it's freezer and a small refer on the bridge which we usually shut off while anchored as in normally has extra soda pop. I unplug the freezers at night except while freezing something from warm. When anchored, I usually hook up one freezer on propane and lift the bail on the ice maker to keep it from dropping ice which takes a lot of extra power. We are careful with power consumption while at anchor but do use a bit of power. In the evenings we usually have one or two TVs running, one or two satellite receivers running, some lights, satellite antenna, anchor light, and mostly low watt florescent table lamps (plus misc loads like heads and pumps). This usage does not run our inverter/house bank below 50%. Now I could run our gen set longer and use more power, by leaving freezers plugged in for example but it is not needed. I do this with our 130 amp inverter charger throttled back to 100 amps. This keeps the 00 welding cables very cool. You may ask why we have so many freezers, it is because we are gone for 7-8 weeks in the summer on our one long trip of the summer and there are few places for provisions where we go.

[Woodsong]

I just don't like the sound of the generator running all the time and even though we are diesel, I don't like sleeping with the generator on due to potential issues that could arise. I think I am going to add a golf cart battery bank to our 4d and may look into upgrading the charger as well.

[mmichellich]

Woodsong wrote:
I just don't like the sound of the generator running all the time and even though we are diesel, I don't like sleeping with the generator on due to potential issues that could arise. I think I am going to add a golf cart battery bank to our 4d and may look into upgrading the charger as well.

I could not imagine running a gen set all night. Most folks you are anchored with will complain if you gen set is still running at 8 PM or maybe an hour later. On the flip side, starting it up in a crowded anchorage before 8 AM would also be frowned on.

[ksanders]

cosmo777 wrote:
Kevin, and others....

Since getting as many amps as possible back into the house bank is good thing, what about installing an ACR between the generator and the house bank.

With this, its seems that once the generator has topped off its own battery, it can then send amps to the house bank.

So then the house bank would not only be getting charged by the inverter, but also receiving excess amps from the generator alternator.

There's nothing wrong with that idea. I have no clue as to the size of the alternator on the generator but it couldn't hurt.