Battery switch

Wandering Sagebrush · Posted: Tue Feb 21, 2012 2:45 pm Post subject:

Hi Marty,

My two cents worth... Move the Battery Switch to a readily accessible location. I set my boat up with #1 being the starting battery, and #2 as the house. After starting the boat, I recharge #1. If the house battery has been used, I will recharge it for a while. I never leave the switch in both for the reasons mentioned above.

Steve

ferret30 · Posted: Tue Feb 21, 2012 4:36 pm Post subject:

I hope this is on topic enough for this thread... I have two Interstate batteries, one group 24 cranking and one group 27 deep cycle. They are 5 years old and need replacement.

I am thinking of switching to a matching pair of Interstate SRM-24s, and while I'm at it, I will likely be replacing the battery switch with a Blue See Add a Battery system:

[url]westmarine.com/webapp/wcs/stores/servlet/ProductDisplay?catalogId=10001&partNumber=8646275[/url]

This seems like a very simple solution, even more so than adapting my setup with a stand alone VSR. One thing that confuses me is that people have said a switch like mine (Guest 1-both-2-off) could be substituted for the Blue Sea switch from that combo. I don't see how since with my switch (I believe) you are selecting a battery for cranking and house power -- the same battery! With the add a battery setup it looks like house runs on the house battery, the motor starts from the cranking battery, unless you select BOTH in an emergency. Essentially they would be isolated, and my systems aren't!

localboy · Posted: Tue Feb 21, 2012 7:00 pm Post subject:

ferret30 · Posted: Tue Feb 21, 2012 7:59 pm Post subject:

Will-C · Posted: Wed Feb 22, 2012 3:24 pm Post subject: Battery switch

First, after looking over this thread I did not want to be providing bad advice. I should have realized everyone’s boat might be set up a little different. What we do based on the way our boat is setup might not be the best thing for someone else who’s boat is configured differently. Our boat was setup with two of the same type of batteries with a simple two battery switch Off /one on/two on/one and two on. We use a pair of Interstate deep cycle group 27 batteries. My motive has always been to keep everything as simple as possible while still getting the job done. Our boat came with a shore power and onboard battery charger standard. When the boat is not in the water it sits in the driveway with shore power connected powering a small electric heater and the on board battery charger is left on. We are going into our fourth year with our boat with the same original batteries. I service the batteries every year in the spring. They take some distilled water and I use petroleum jelly on all the connections. We spent about 50 nights sleeping on our boat last year and trailered it about 10,000 miles. So far so good. For me battery life I rate at five years. At the end of next year I’ll consider replacing my batteries with some Sears Deep Cycle Diehard marine batteries which are in the hundred dollar each price range. They have gotten decent reviews on Hull Truth etc.
See them www.sears.com/diehard-marine-deep-cycle-rv-battery-group-size-27m/p-02827524000P Two of my previous boats a Scout 18’ Center Console and a 24’ Grady White Offshore were rigged the same way as our C-Dory. We always used two of the same batteries and the same simple two battery switch. Because I carry a generator on extended cruises I can always use the generator connected to shore power to charge batteries if need be. Our normal power consuming devices are a 400 watt inverter that powers a wireless internet router with cell card, cpap machine an LED all around light at night led cabin lights, an Espar D 2 diesel heater, laptop, IPad, GPS on anchor watch it we are not at the dock. I have always been able to do overnightners so far at least using one battery and still been able to start my engine without having to switch to the second battery. So for me at least I don’t really see the need to rush to buy a Blue Seas voltage sensitive relay. If someone were to replace one battery they could just charge them individually not on both. For me though I have always replaced the batteries in pairs. Having two different batteries was not for me either. I guess there is some savings in dollars having a smaller start battery but in the economic context of boat ownership I say REALLY? That savings is then spent on the voltage sensitive relay? So if you avoid parallel charging is there really a need for voltage sensitive relay? Not trying to be argumentative; just trying to understand the need for setting up a boat this way. Is there a problem with a standard on board charger if your batteries are the same or different types or can the on board battery charger sense the voltage of the batteries separately ? Just wondering?
D.D.

potter water · Posted: Wed Feb 22, 2012 3:37 pm Post subject:

Your on board charger needs to be a two bank charger if you want to continue using mismatched batteries. And you need to have a VSR in the system if you want to charge mismatched batteries with your engine alternator. Simple as that. A two bank charger is basically two battery chargers in one, one set of leads for each of the two banks and batteries.

I couldn't agree more with simplicity. My boat has two Suzies with separate start batteries. Either Suzie will charge the house battery through the voltage sensitive relay controls. So, each motor, port and starboard has a separate battery on or off switch. There is a separate house battery on or off switch, and a fourth switch that ties all three batteries together in parallel for emergencies. It is a very complicated system with several VSR's, dual bank charger and so on, and about the time it fails, I'll probably put a much simpler system in, more manual than automatic as it currently is.

However, so far, the whole complicated system works and everything charges, etc.