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Re: Battery configuration
Posted: April 7th, 2016, 3:35 pm
by SanJuanDreamer
I have 1998 Mariner 350, I'm not sure about two house batts and what you might be expecting.
I run (8) 6v batteries and then the two 12v start bats. With the inverter and three days at anchor, I run the frig constantly, Anchor light at night and about an 2 hours of TV for selected movies.
At the end of three days with out a charge, the meter shows 3 out five lights on...whatever that break down to.
Re: Battery configuration
Posted: April 7th, 2016, 11:21 pm
by Viper
Interesting thread, first time reading it, wish I caught it sooner. Some things I agree with, some, not so much! Suffice it to say, as mentioned, ideally you want one start battery per engine, each isolated from the other, and an isolated house bank. Don't mix battery types in the same bank.
There should be a method to parallel engine banks in case one of the engine batteries fails to start an engine. This should not be done with a battery selector switch IMO (don't like them) but with a device that parallels for the duration of cranking then disengages once the engine has started. There are a couple of ways to accomplish this, and please, no jumper cables.
Charging considerations are another thread. While the house charger hookup is pretty straight forward, charging all the banks off the engines requires a little more forethought to be done right if one is to stay within certain guidelines.
While the inverter install seems high, I always caution that it's very easy for us to judge without actually having assessed what's involved. I liken it to someone giving a number over the phone site unseen just to get the job then hand out sticker shock after the job is done. Something I would never ever do. If I can't see it, I don't price it nor would I comment or criticize on a price from someone who has seen it until I see it for myself. Accessibility to the areas of installation can mean the difference between 10 hours vs 30. The complexity of a particular install could also have a huge impact on the amount of time needed. The only way you'd know this is if you've been on board, discussed the customer's needs, then assessed what it would take to make it happen. I've installed several that have ranged from just a few hours to much much more. No two installations or boats even of the same model are ever exactly the same and always present individual challenges. And I can tell you that if you do not hook up an inverter properly in a marine application by marine standards, you're taking your life and everyone else's on board in your hands. I've seen some pretty dangerous inverter installs.
An inverter purchase on its own is in some cases the cheapest part of the system. The install, cabling ($$), and other hardware can also be very expensive depending on the installation.
How did the inverter install go?
Re: Battery configuration
Posted: April 8th, 2016, 7:52 pm
by feeez
The current update from ours is.
I replaced one of the group 31's with 4, 6 volts and that was certainly a big step forward. I also installed a Victron battery monitor and that has lead me to find out that my battery charger is not working properly (another thread). I am installing a new charger (Promariner 1250p) ASAP this spring and we will see how that works. I will perhaps tackle the whole isolation thing at a later date once I understand it better. This season we will evaluate if my need for a inverter install is warranted or not. I am going to install a 12V accessory / USB receptacle in the salon this year and I can run my TV from one of those plug in inverters with no problem.
Now.... if it would just stop snowing up here we could get on with this!!!!

Re: Battery configuration
Posted: April 9th, 2016, 1:00 am
by Lyndon670
Next weekend Fraser, 17C and the shrink is coming off!
Re: Battery configuration
Posted: April 9th, 2016, 9:27 am
by Viper
Yippee. Can't wait.
Re: Battery configuration
Posted: April 9th, 2016, 10:18 am
by CaptBob
17 C, Oh my that still sounds cold to these southern bones. It's all the way to 62.6 F here in Nashville today! That sounds much warmer!

(Well tomorrow it's supposed to be 65F.
I've always thought about changing the house batt to a couple of 6V. I think I will look into it at the next battery replacement. I would be a bit nervous about loosing dedicated starting batteries for each main and genny though. I understand the logic, but like a spare tire, I'm old enough to like having it. (I realize that I have 2 cars that have never used the spare, and the Admiral's car has no spare)
On the other hand, when our summer heat/humidity really kicks in we run the genny from dock to dock.
Re: Battery configuration
Posted: April 9th, 2016, 9:39 pm
by feeez
Re: Battery configuration
Posted: April 15th, 2016, 2:38 am
by feeez
I received the new battery charger today (promariner 1250P). I was reviewing the installation instructions and it all looks pretty straightforward; proper wire gauges for the length of wire run etc etc.
I will be installing it in the 3 bank configuration and I have a question the stems from the wiring diagram. There is a single negative wire coming from the charger and connecting to a "main grounding bus to engine negative". Also, the case ground wire also connects to the grounding bus. Finally all the negatives from the batteries connect to this buss.
My current charger (Charlse C-Charger) has the negative wire connecting to the negative of one of the battery banks. All of the negatives from the battery banks are interconnected with a common negative and then to the engine(s). When I reconfigured my battery set up last season I confirmed this set up with Charlse tech support and they gave it the greeen light. As long as all of the battery negatives are interconnected the negative from the charger can reside on any of the banks. The existing charger does not have a case ground wire. I assume that this was an ABYC standard that has come along in recent years.
So, should I be introducing a negative bus into my configuration or can I just connect my new charger the same as the existing one?
I know this is a lengthy post but as always I appreciate the feedback.
Fraser
Re: Battery configuration
Posted: April 15th, 2016, 2:59 am
by feeez
One further note on the case ground. The instructions also state that this must also be connected to the boat's bonding system. I assume this one of those plates affixed to the hull in various locations.
Thanks
Fraser
Re: Battery configuration
Posted: April 15th, 2016, 10:24 am
by AaHubb
Assuming properly sized cables and clean connections then yes you can connect the negative lead where convenient. The case ground to the ships bonding system guards against galvanic corrosion from a bad shore power connection.
..Aaron