battery question

[captn-tin]

the trolling motor on my lund is 24v, wired in series. since i am still having noise problems with my lorance332, i have decided to try wiring it to 1 of the 2 12v trolling batteries that are not connected to the charging system. when checking voltage on the 2 poles of 1 battery i get 12 volts. when i cross the meter to + side of #1 battery to - side of #2 battery it read 25v. question. is it ok to wire my sonar unit to 1 of the 12v batteries, while leaving the batteries connected in series for the trolling motor. hope i explained my question ok, but remember i'm a butcher, not a electrican! thanks in advance...bill

 

[floatingwoody2006]

Re: battery question

I asked a very similar question earlier this week Bill. Check this post out..I believe the answer to your question is yes you can connect to just one of the batts to get 12 volts. <br /><br /> http://forums.iboats.com/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=27;t=003229

 

[Silvertip]

Re: battery question

Yes -- you can wire to either of the batteries but the safest way to do this is to wire to the battery that has the negative cable running to the trolling motor.

 

[captn-tin]

Re: battery question

Thankyou Both for the help with this project.What a great site this is! One last question for Upinsmoke. Not knowin much bout that thar e-lek-tristi would you please explain to me why it is better to run the unit from the battery with the ground going to the trolling motor. Thanx again, very much...Bill

 

[Silvertip]

Re: battery question

Why did I know that question was going to be asked? It is simply a way of preventing what's called a "ground loop" and it may also reduce or even eliminate the chances of motor electrical interference affecting the locator since the ground point is the same for both devices. Improper grounding of electronics can cause some weird things to happen. One way to reduce that is to use a common grounding scheme. Ground is ground regardless whether its 12V, 24V or 36V. You proved that the NEG terminal on the battery with the POS line going to the motor was not ground but rather 12V above ground even though it is a negative terminal. In other words it and the POS terminal on the other battery are the 12V point in a 24V system. It all gets down to where you take measurements. But in the end the trolling motor ground and your locator ground should be the same point in the circuit even though there are two POSITIVE points (+12 and +24V). Long answer to a short question. Clear as mud????

 

[captn-tin]

Re: battery question

UPINSMOKE CLEAR AS MUD ! I pity the poor retired butcher that asks me to explain your response.HA Again thanks to all......Bill