12 Volt Battery Gauge

[crappace]

I am trying to find an inexpensive gauge to flush mount in my perm for my batteries which will be hooked together to make one big 12 volt ( i dont remember if thats called parallel or series ).

1. Anybody know where I can find a accurate cheap one?

2. With the batteries hooked together, do you only have to hook the charger to one and both will get charged? or do you need two sets of leads to charge both? Thanks

[ice_it_06]

Digital are the best but for under $20 you can get a dash mount regular volt gauge. I got two at Auto Zone the past year for my houses. I screw them under the bunk frame where the batteries sit.

The fist battery in line from the charger will charge the second connected in parallel. + to +, and - to -

Use equal batteries in size, age, and rating.

[river-rat4]

Crappace,

Think of electricity like plumbing....(supply)

it takes the path of least resistance...

a plumbing valve would be equal to a switch or toggle...

Two batteries, hooked up to one charger (like a Y) would charge at an equal rate, assuming both batteries were good or the same. (paralell)

Be carefull with batteries! DO not cross the polarities!!!(- to + = BAD BAD!!!)

If the battery is not maintenance free, be sure to open the the top so it can vent...

[eurolarva]

Volt meter is not going to show you much. A fully charged battery is around 12.75 Volts where an almost totally drained battery is 12.0 Volts. The main purpose of a volt meter on a boat is to show you that the alternator on the outboard is charging the motor which will usually shoot the voltage to between 13.5 volts to 15 volts.

[wingnutken]

I purchased a nice battery charge indicator on hsolist for 25.00 + shipping. Do a search for 12V LED battery charge indicator and you will find the same one that I bought. I have it hooked up to a on/off/on toggle switch so I can switch back and forth between batteries. Ken

[ice_it_06]

A good digital meter will show you the level/rate of discharge be a alternator part of the equation or not. I've never experienced a 12v car or deep cycle battery being @ full discharge before 10.5 volts minimum unless it was a badly abused and old battery that was taken below 10.5 which is not a good practice.

[crappace]

I've heard before that similar sized batteries should be used when hooking them up in parralel (12v +to+ and -to-) or series (24v +to- and +to-). Why is this? I have a large semi battery and the biggest Diehard they make but they are not near the same size.

[ice_it_06]

You want the batteries the same group size and amp hour capacity. The batteries if not equal in health/condition/age will be only as strong as the weaker battery. One drags down the other so your charge/discharge differences become greater.

Charge the batteries (parallel) charger + to closest battery +, and the charger - to the second batteries -.