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If the battery checks out fine, then consider adding a main bus breaker (http://www.basscatstore.com/8amppushbut … ker-1.aspx). Even when off, some electronic devices still have a draw. I removed my radio for that very reason, plus I never used it. The breaker works well for me.
Thats definitely a current draw. I would want to know where the power is going. If it is a wire fray or shorting circuit it could lead to all kinds of problems. A radio wont draw enough power to cause a week battery or you would never get away with leaving your vehicle for a week. With some patients and persistence youll get tto the bottom of it. Please let us know what you find.Practice Angling CPRCatchPictureRelease2010 PIV 200SHO
I had a similar issue and installed a perko battery disconnect.
Parasitic draw can definitely do it. You can easily test by disconnecting everything from the battery except the charger. Bring it to full charge, and then check it about 12 hours after charging, and then daily for 5 or 6 days all the while with nothing connected. Easy by using voltmeter readings. If it holds charge, your problem is verified and will be resolved by adding a disconnect as suggested. Some other possibilities are battery, charger, charging habits, wiring or connection issue, or electrolyte level in flooded battery.
The big motor has a small but steady draw and will pull the battery down over a few days. I added a battery disconnect switch also in addition to the breaker shut-off.
Thanks for the great advice, i am going to try and narrow it down and will post anything I find.
An ammeter installed between the battery and each wire attached to the battery one at a time, will locate which circuit has the draw. That will give you a direction in which to start. Keep in mind that some circuits will have a small maintenance draw. Once you find the issue, perhaps you can post some numbers here and get feedback as what is and what is not normal. A week is way to short a time for the battery to be dead. You should get the battery and your charger tested as first steps, though.
Where does everyone mount the main battery disconnect?
The 25A circuit breaker should be mounted on the positive post if you dont have one. I put a blade-type switch (works like the Perko) on the negative post.
If a move to a 27 series is an upgrade, then you may have a 24 series in there now, which is way too small. For your opti and those electronics, get yourself a good quality 31 series battery. AGM or wet, your choice, with your charger being a factor in battery choice. Make sure to direct wire your graphs to the battery with 10 or 12 gauge tinned wire, and fuse them. Do not use the boats wiring harness. BCB now offers a very nice power cable with block for proper wiring of electronics.
I will have to look at exactly how the shop ran all of the wiring when I get home. I have the NOCO genius 4 bank charger. My charger is lighting up with all green lights, so the batteries are charging, I just couldnt start my boat when it came time to head back to the landing.
I HAD TO MOVE OVER TO ONE OF MY TROLLING BATTERIES WHEN I PUT A HELIX 10 ON. IN THE SUMMER WITH PUMPS RUNNING 31 AGM GOT WEAK.
You have to watch battery drain. A good 12″ depth finder draws OVER 5 amps. Two will be 10. Three will be 15. That will suck a 24 or even 27 dry if you sit and fish for an extended period without running the big motor to charge it back up. Optis require a min of 800 CCA BY THEMSELVES. Two or three sonar units only add to that. Most recommend 1000 CCA. If you can go to BBC, Don has posted a list of batteries tested by Mercury and listed as “acceptable”.2008 Pantera Classic2014 Mercury Pro XS 200
With all the tranducers running you do draw a lot of current. Add the livewells a radio and your looking at a lot of battery reserves used up in 8 hours. Then the normal angler runs to a number of spots which means the starting motor draws more power than the outboard charging system can supply. Put that all together and it is a small wonder that even the large 31 series batteries get us through the days.Practice Angling CPRCatchPictureRelease2010 PIV 200SHO
I had no idea that 9″ units would draw 5 amps until last week. I was re-doing connectors that had the wrong size hole for normal 5/16″ battery posts. Turned on my bird 998 and 4.9 amps. And I have two of em plus a 787 built in. And those 1000 gph pumps have pretty stout motors and current draws. And then there is the opti that requires a bunch. Motor has to spin three (3) times to give the air compressor enough time to build up enough air pressure to light the motor, then the computer, all the sensors, and the biggee which is that starter motor (hence those really big wires). Better be quiet, because all that current ends up as 90% heat. The environmentalists will want a max on-time per day to prevent adding to global warming. 2008 Pantera Classic2014 Mercury Pro XS 200
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