Electrical 1/2/all switch

I

Izzy

New member
There is a 1/2/& all - switch on My 22' cruiser, located near the batteries. Is it best to have the switch set at "all" ?
Does this put a load on both batteries equally? Would someone please explain the purpose of this switch and when to "turn the switch" to a desired setting?
Thanks
 
Typically one of the positions on the switch is connected to the start battery and the other to the house battery- 1 and 2. These batteries are often identical which is not a great idea.

When at anchor turn the switch to 2- house to keep the 1- start battery from running down also and be unable to start it the next morning. Then when you are ready to go turn the switch to 1 and start the engine. Then turn to all so the engine will charge both batteries.

Leave it on all while at the dock so the shore power charger will charge both. If you pull it out on the trailer, unless you plug it in at home like at the dock leave it on 2 just like you were at anchor to save the start battery.

Why not use the same type of battery for each? Well you can if they are AGM types as there really isn't any difference between starting and deep cycle house batteries for AGM types. But there are very few real deep cycle flooded cell (non AGM) batteries. So use two 6V golf cart batteries wired in series for your house (and most CDs don't have room for this) then either use AGMs for both 1 and 2 or an AGM for house and a normal flooded cell starting battery for start.

Using standard flooded cell batteries for house loads whether they are labeled deep cycle or not will usually result in failure sooner than two GC batteries or an AGM battery.

David
 
DavidM said:
whether they are labeled deep cycle or not


Labels are cheap! Quality not so cheap and harder to find! The deep cycle batteries I use in my off grid installation are made in Canada - Surrette/Rolls. Most banks I have installed over the years have given me 7 to 10 years of service. They are cycled daily but never drawn down too low and fluid never below level of plates. A quality, charger that is sized to the bank is also important.

Regards,

Rob
Click to expand...
 
Izzy":2zu71sr7 said:
There is a 1/2/& all - switch on My 22' cruiser, located near the batteries. Is it best to have the switch set at "all" ?
Does this put a load on both batteries equally? Would someone please explain the purpose of this switch and when to "turn the switch" to a desired setting?
Thanks
Click to expand...

I switch to All/Both when I get to the boat to charge both banks while running. That's where it stays until I leave the boat & return to Off. If overnighting, while at anc. I will switch to #2 witch is the house bank on my boat. :wink:
 
Leave it on all while at the dock so the shore power charger will charge both. If you pull it out on the trailer, unless you plug it in at home like at the dock leave it on 2 just like you were at anchor to save the start battery.
Click to expand...

Careful with this kind of advice, as not all installations are the same. Case in point, my original charger, and possibly my new charger, warned not to put the switch in both when the battery charger was on. It's installation has the batteries separately wired to the charger, so even with the battery switch in the off position, my charger is charging the batteries. (Switching the switch to both, closes a loop between both batteries and their individual charging posts on the charger.)

I use the start battery for starting the engine, and the house battery for overnight. When running the motor then, I go to both to charge the batteries. Also, you never want to turn the switch off with the motor running, which could damage your altenator components. And even switching between the various 1, 2, both positions could present a problem unless you have the type of switch that doesn't completely open the circuit between those settings. Colby
 
My take on 22 batteries is that they should be equal. There are plenty of marine batteries which are more than adequate to do both house and engine start. My favorite is the group 31 AGM from Sam's Club: "DuraCell" Made by East Penn: same as Deka. Most boats come with a group 24--which is a bit small. I feel minimum are two group 27's. The golf cart batteries are great for a larger boat--not much space to put them in a 22 or 16. Even the 25 it is a pinch.

The reason for equal batteries, is for similar charging characteristics. When batteries are combined--as when in "all" It is best that batteries be same type, size and age. If not there can be unequal charging.

The idea of rotating batteries between start and house is a good one. When you "start" use #! one time and #2 the next etc. After the engine is running, then combine the batteries--with "All". When you get to a destination, anchor or stay overnight go to one battery. (#1 or #2, but not "all".) That way when you go to start the engine, there should be one fully charged battery.

I prefer to "automatically " combine. This is done with a voltage sensitive relay (VSR) also called a combining relay. When the engine starting battery gets to over 13.7 volts the VSR combines the batteries, and they both charge. When the voltage drops below 12.7 volts the "combiner" or VSR disconnects the two batteries leaving the start battery isolated. This gets away from "I need to turn the switch to "All" or leaving them both connected and waking up to two dead batteries.

There are many more things one can do for battery management. if you have complex systems three batteries and battery management with a gauge such as the Victron 702, which monitors amps used and amps put into the battery. It also gives very accurate state of charge and voltage.

Do not discharge a battery to less than 50% state of charge. This is 12.2 volts at a steady state. (no current in or out for an hour,)

I have been experimenting with a lithium ion battery which has the "power" of two golf carts (6 volts in series to give 12 volts and 110 amp hours usable). This battery weighs 29#, is in a group 24 size case, and should be good for at least 10 years. It has 110 amp hours usable. Down side is cost, and the necessity to keep isolated from other types of batteries (It is a slightly higher voltage at rest, and if combined with a flooded lead acid, AGM or Gel, would overcharge that battery and harm the Li ion. There needs to be a special charger to top it off, but bulk charging can be done by motor or standard battery charger.
 
One thing that has been mentioned a couple of times is to switch the 1-2-Both-Off switch after the engines are running. Some switches are not made to switch while there is current passing through and moving the switch while the OB's are running could damage the charging circuit. There is a difference between switches, (make before break, or the other -- sorry I don't know that much about which) but My practice is to not switch on my boat with the engines running.

I do use a volt meter type battery monitor and keep very close track of my battery levels. Generally I am on the " Both" position, but there are occasions when I will switch to 1 or 2 depending on the levels, manually trying to keep the charge levels equal. I have 2 Group 28 marine Deep cycle batteries that are still working fine after several years. When not in use on the water or boater homing, I keep them on BattryMinders at home.

Harvey
SleepyC :moon

JC_Lately_SleepyC_Flat_Blue_070.thumb.jpg
 
All of the current switches used on C Dorys do "make before break" You may find some off brand Chinese which don't--but that is pretty much a thing of the past.
 
colbysmith":3lpfryj5 said:
Careful with this kind of advice, as not all installations are the same.
Click to expand...

There is no shortcut to learning your particular wiring system. I have a solar panel that goes only to the house battery. When the boat is on the trailer (and outside), I leave the batteries on "Both" so that they stay charged. Not a common situation, but it works for me.

Mark
 
I am the odd man out here, or just an oddball, but I did away with the 1/2/All switch and have a simple On/Off between the big motor and the battery bank.

I run a 1500 watt inverter that requires both batteries when running the coffee maker so I have them cabled in parallel with no means to quickly separate them. The motor, as well as the shore power charger, charges them both at once all the time.

I use the marine combo batteries that Costco sells and the last pair I changed after five years just for drill when I put the new motor on last year - they were still performing adequately.

If I need to completely disconnect the house from the battery bank I have a 150 amp inline fuse for the inverter and a 100 amp breaker to the house.

The kicker has a smaller dedicated battery that could be used to start the main if I were ever to run the big batteries too low so I don't worry about it.
 
We have the VSR system that Dr. Bob speaks of. We had the dealer install it when we bought our boat. It is a nice system. You have a separate switch for the engine, house and a third switch (All) for both batteries. It is nice to not have to worry about the engine battery being drained and not starting the engine for you the next morning.
 
Personally, I like the 1-2-All-Off switch, as it is simple and easy and takes up less space than 3 switches. I keep pretty close track of where my battery level is so even though any switching is done manually, I really rarely have to do anything but turn that switch when I want to go in the morning. I do have a Cig plug that goes directly to Battery #1 that I run my CPAP on at night, and run my rear view camera on when towing.

Harvey
SleepyC :moon

Friends_Cal_09_10_Oct.thumb.jpg
 
Back
Top