how neccessary is a 2nd battery?

[fishdawg]

Im considering adding a 2nd battery to the Crestliner.

 

Currently I have a 27 series start/crank batt. and it runs the sonar, VHF, FM, lights, bilge, downriggers, Sub Troll, two 12v cigg. plugs, ect... The alternator from my 30hp Johnson is the charge source.

 

I'll be adding an additional (and higher powered) sonar/gps to the grid this winter. How neccessary would a 2nd battery be in this situation?

 

I should also add that more often then not when most of the electronics are in use I am trolling.

 

If I do get a 2nd batt. I am considering wirring them in parallel.

 

If I dont get a 2nd batt. I am thinking of installing a solar powered charger.

 

Ideas? Suggestions?

[Sinker]

I'd add the second battery.

 

If for nothing else, piece of mind. If your single battery fails, your out of luck. I run two all the time. When one failed, I really missed the added power of the second battery.

 

The second battery wired together in a 12 V circuit will increase your run time substantially.

 

Do you run a TM on that boat? Electric start motor? It must have a manual start on it as well though, no?

 

S.

[Muskieman]

Yep get one.....

 

I have all the stuff you have.

 

One Dual Purpose for the cranking and the electronics.

and a Deep Cycle strictly for the TM.

 

Randy

[fishdawg]

30hp is electric start ( has manual option, never used it, some "McGyvering" needed to do it)

 

Minnkota on the bow has its own deep cycle batt, bow mount sonar has its own gell cell batt

 

so running 2 similiar 27' batts in parallel would suffice for my set up?

(+ to +, - to -, and motor + to one batt and motor - to the 2nd batt?)

[Tom McCutcheon]

It is always wise to have the second battery, especially when using all the electronics you have. Also install a battery switch or isolater so that you can use/discharge one battery (deep cycle) only, when not using the big motor. This is the one I had all my electronics connected to, (radios, graphs, additional lights, Fish Hawke temp probe, etc. etc). This saves the main battery for start up and then switch to both to recharge when running. Of course that all depends on the size of the alternator on the big motor.

[Woodsman]

Hooking up an older battery to a newer one even with similar ratings is not a good idea. The weaker one will steal from the better one.

Installing a switch to go back & forth between the two is the best bet.

[Tybo]

Mark,Use the two with a battery switch.Then run the riggers on the second battery and the boat off the main cranking.

When your done with fishing.Start the engine with the main cranking then switch to the second to re-charge with engine.

Then when you get home switch too both for the maintenance charge.

This will help prolong the life of the batteries and your alternator.

[Roy]

so running 2 similiar 27' batts in parallel would suffice for my set up?

(+ to +, - to -, and motor + to one batt and motor - to the 2nd batt?)

 

Parallel would be + to + and - to - on the batteries, then one of the battery's - to the motor's black and the + of the SAME battery to the motor's red.

[Dabluz]

Parallel would be + to + and - to - on the batteries, then one of the battery's - to the motor's black and the + of the SAME battery to the motor's red.

 

By all means, buy a second battery. Buy a deep cycle battery and use a switch to either recharge your cranking battery or deep cycle battery. However, when you get home, recharge the deep cycle battery with an intelligent battery charger. Be careful as to which battery charger you use because not all battery chargers can recharge a real deep cycle battery. The cranking battery is not as difficult to recharge.

 

As for the solar panels....forget that option. You will need too many panels to be able to recharge any battery. Solar panels (a wall of them) work great at the cottage when you only go to the cottage on the weekends. A bank of real deep cycle batteries, solar panels and a good computer controlled charger costs a small fortune.

 

To recharge a deep cycle battery that needs a bit of juice to top it off, you will need at least 2 or 3 amps at 14 volts. This means 30 to 45 watts of power.

[Fisherman]

You might want to pay attention to changing the battery switch position while the motor is running. Some highly recommend NOT to do it as it may/will fry your alternator on the motor. That's for you to research.

[strik]

This spring i added the extra battery glad i did i was out on Lake Huron and cooked the one batt i was able to turn my switch over and crank up the main. My main and my kicker both have the ability to charge the batts.

 

The switch i have says one/two / all and i am able to switch as the engins are running. As i hate to turn off one engin before the other is running.

 

I aslo have started to bring my motomaster eliminator power box 800 if nothing else i can charge up plug in divices(cell phone/ flashlight ......) with this it also another back up.

 

For the extra it cost to run two batt i think it is worth it or at least get some kind of power box. Then you can have the power when you need it. Could be keeped in car to jump batt that are dead or camping or power outages the list goes on.

 

Best of luck

 

Strik

[mercman]

This spring i added the extra battery glad i did i was out on Lake Huron and cooked the one batt i was able to turn my switch over and crank up the main. My main and my kicker both have the ability to charge the batts.

 

The switch i have says one/two / all and i am able to switch as the engins are running. As i hate to turn off one engin before the other is running.

 

I aslo have started to bring my motomaster eliminator power box 800 if nothing else i can charge up plug in divices(cell phone/ flashlight ......) with this it also another back up.

 

For the extra it cost to run two batt i think it is worth it or at least get some kind of power box. Then you can have the power when you need it. Could be keeped in car to jump batt that are dead or camping or power outages the list goes on.

 

Best of luck

 

Strik

 

This is an excellent idea They go on special all the time at CT.

[BillM]

If you've got the room, it's silly not to have one.

[Tybo]

You might want to pay attention to changing the battery switch position while the motor is running. Some highly recommend NOT to do it as it may/will fry your alternator on the motor. That's for you to research.

 

The only thing the switch can do is pop the diode if you turn the switch off.

If there is some thing wrong with your battery and pop the alternator has nothing to do with the switch.

[Spouph]

Yes definately run two. Also I would strongly suggest installing a selector switch. I run my bateries in the both position, my kicker and main enging both are able to recharge as I run. The reason I do this is to keep the power clean, when you fire up the down riggers and have the radio's going and the fishfinders running. The extra amprage keeps the spikes and surges to a minimum. Those electronics are fragile and expensive. My suggestion to you is to buy two Identical deep cycle bateries I love the Nautalis and replace them every five years. When you wire them up I keep my bilge pump and trim seperate from the switch so that you can operate them with the selector switckh off. I turn the switch off at the end of each day. this will only drain one battery, if the bildge is running alot. You can always get the boat started because the other battery is charged. Then I label both batteries and alternate them each season. It works great I have never had any battery troubles. I drain and trickle charge my batteries twice in the off season. Don't use the switch while the boat is running my father fried the alternator on his boat doing just that. If you dry dock the boat all the time leave the bildge pump on the switch, if it tips or the float switch get's stuck the pump will burn itself out. I had to replace one for that reason, but I put in a new one with water sensing technoligy. I leave my cover open on the boat all season in the dock, my bildge has never drained my battery, but the longest I went without running the engines was two weeks. Hope this helped