Battery Help

[vangoalie]

I know this has probably been covered before so I apologize in advance if so. I want to add a second battery to my boat to run my electronics when I am trolling and not on the main motor so that i can save a starting battery. I have two ways to do it, a 1-2-all battery switch and I also have a M-ACR and a M-Battery switch have accumulated both planning for the addition. What way would you recommend going? If the ACR relay route then would the M-ACR be enough its a Mini-ACR rated to 65 amps, I have a Merc 115 Optimax. What gauge wire would be required for me to do this? I have been wanting to do this but have resisted as I worry about messing something up. And any other advise anyone could offer too.

Thanks for your help, this forum is a great resource!

 

[Brando]

The mini should be adequate it’s sized by alternator output. Would recommend the ACR over the 1-2-all switch. Tie your kicker into the secondary battery (house) you’ll need some bus bars / fuse block depending how you decide to wire things don’t load up your battery terminals with connections use the bus bars. Follow blue seas directions online lots of info regarding installation.

 

[vangoalie]

Thanks, any thoughts on the gauge of wire for this?

 

[Baxter]

Ya, definitely use bus bars. I am in the process of cleaning things up with those.


Cant say 100% what gauge you should use, but on my boat all the major cables are 2ga (from motors to batteries & switches, and the negative battery to battery, and connecting batteries to bus bars - using 2ga for all of it. Might be overkill, not sure, but certainly can't hurt. Some of that wiring was done when the boat was new at the dealer, so I have to assume that the use of 2ga is correct.

When I added the bus bars, I used 2ga just to match up everything else, figured at least this way I never have to worry about it being too small.

Most of the lines running to accessories etc all appear to be 10ga, and most of those were done at the dealer, or right at Kingfisher (not sure who rigs things up like lighting, bilge etc)

I will be running a new line to a fuse box at the helm soon too, but will probably use 6 or 8ga for that (although preliminary checks show 10 may even be sufficient) but will figure it out for sure when I decide what all it will be powering and what my requirements will be.

 

[kevind]

depends what your alternator puts out if the alternator puts out
60 amps or less #6 with a fuse rating 75-90A
61 to 80amps #4 100-125A fuse
81-100amps #2 150A fuse
101 to 120 amps #1 175A fuse

This comes from the blue seas installation guide

https://www.google.ca/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&ved=2ahUKEwjip82y9fLyAhU6EDQIHagTA80QFnoECAMQAQ&url=http%3A%2F%2Fbluesea.com%2Fviewresource%2F505&usg=AOvVaw0L1rfrnWXe9cOpDwgr3mJg

 

[Baxter]

depends what your alternator puts out if the alternator puts out
60 amps or less #6 with a fuse rating 75-90A
61 to 80amps #4 100-125A fuse
81-100amps #2 150A fuse
101 to 120 amps #1 175A fuse

This comes from the blue seas installation guide

https://www.google.ca/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&ved=2ahUKEwjip82y9fLyAhU6EDQIHagTA80QFnoECAMQAQ&url=http%3A%2F%2Fbluesea.com%2Fviewresource%2F505&usg=AOvVaw0L1rfrnWXe9cOpDwgr3mJg

Interesting. My F90 puts out 35 amps I believe. I wonder why the dealer originally wired it with 2 gauge. Sounds like WAY overkill. (not that its a bad thing, but excessive for sure.)

 

[kevind]

Interesting. My F90 puts out 35 amps I believe. I wonder why the dealer originally wired it with 2 gauge. Sounds like WAY overkill. (not that its a bad thing, but excessive for sure.)

they probably just use the same 2 ga for all there connections from battery to motor. Really not worth it to them to size it to each motor put on. 2 ga will cover any motor they probably install

 

[zurk]

i wire everything with 2 guage. flexible enough to go anywhere and large enough so it wont catch fire.
2 guage to blue seas dualbus hubs and 12 guage to everything from the hub.
the mACR does NOT work with non standard batteries like lifepo4. youre better off putting a larger AGM in there - i use northstar NSB-AGM31M and a victron BMV-712 to monitor it. works great with a trolling motor and a start battery.

 

[prodjsaig]

I know this has probably been covered before so I apologize in advance if so. I want to add a second battery to my boat to run my electronics when I am trolling and not on the main motor so that i can save a starting battery. I have two ways to do it, a 1-2-all battery switch and I also have a M-ACR and a M-Battery switch have accumulated both planning for the addition. What way would you recommend going? If the ACR relay route then would the M-ACR be enough its a Mini-ACR rated to 65 amps, I have a Merc 115 Optimax. What gauge wire would be required for me to do this? I have been wanting to do this but have resisted as I worry about messing something up. And any other advise anyone could offer too.

Thanks for your help, this forum is a great resource!

I put in the si acr I think it looks better and has start isolation and remote led option. 6 gauge with blue seas maxi fuses. My alternator is 60amp.

It takes a bit of time but it's really nice to have no running back underway to switch batteries to charge. The remote led is nice gives you peace of mind. I did it for looks as I may sell my boat one day maybe next year.

It is costly maybe $500. Negative bus bar and maxi fuses x2 add up. But if you have to do work on the electrical may as well add an acr.