Battery confusion

Status
Not open for further replies.

M Burd

.
Sep 25, 2008
4
2 32 (2004) Liberty, IN
I have a 2004 Bavaria 32 Cruiser, it appears that I am getting a draw on only one battery. Both are connected, not to each other. When one draws down to a point that I cannot start the engine, I have to switch cable connections to the other battery. I do nto like to draw just one battery, would prefer to draw on both. I am thinking that the house battery is only drawing the lights and potentially radios. The other has the starter and the frig. Should I conect the batteries to each other or possibly move the frig to the second battery? Has anyone installed a stand alone starter battery. I think if I go this route, I will not have any engine starting problems and could potentially double my house battery capabilities. Any suggestions to what I have going on here?
 
Sep 25, 2008
7,075
Alden 50 Sarasota, Florida
Sounds like you have the typical separate house and start battery banks. In that configuration, the engine draws off only one battery; the rest of the boat off the house bank (battery). You would do well to figure out what your typical house power consumption needs are by adding up all the elec demand on your typical sailing cruise is, double that power demand and size your house bank accordingly by adding house batteries in parallel while keeping the start battery separate.

There are a number of alternatives, all equally sound in logic, which make sizing and configuration of batteries a largely personal choice.
 
Jul 24, 2006
628
Legnos, Starwind, Regal Mystic 30 cutter, 22 trailer sailor, bow rider NEW PORT RICHEY, FL
you might want to add a bat select switch, one of those 1 2 both off ones. At least you would'nt have to remove cables off your bat terminals. But, you have draws comming off both and you could end up with 2 dead bats instead of one and nothing to start engine with.
 

M Burd

.
Sep 25, 2008
4
2 32 (2004) Liberty, IN
Thanks for the opinions. On one hand I think I have both the starter and house on one battery.
 

cbsura

.
Jun 7, 2004
27
Bavaria 32 Branford, CT
I have a 2005 Bavaria 32. If your setup is similar to mine then one battery is a dedicated emergency starting battery while the other one is your house battery. If so, above the main battery switch under the nav table is a second switch with a removable key -- engaging the key switches the emergency starting battery into the circuit.

You should probably add capacity to your house bank while still keeping the starting battery in reserve.
 

robgs

.
May 24, 2004
26
Bavaria Vision 40 Rock Hall MD
The current thinking re ship's batteries is to have independent battery banks for the engine start/run function and all other sytems (lights, instrumments, refrig, etc.).
Usually the start battery is a single smaller unit and can be specifically designed (plate design) for starting with rapid discharge and recharge. The house bank can be larger,
often 2 or more deep cycle batteries connected in parallel to provide the capacity to match the expected loads.

Charging systems (shore power and alternator) should be designed to charge both battery banks while ensuring isolation from each other while in service so that a low bank does not draw down the other.

1/2/both selector switches are not recommended.

An excellent source of info is Nigel Calder's 'Boatowner's Mechanical & Electrical Manual'.
 
Status
Not open for further replies.