Battery Switch and 2 Batteries...

rauch0812

Petty Officer 2nd Class
Joined
Feb 4, 2010
Messages
145
We want to install a 2 batteries and a battery switch in our boat. It currently has an Interstate SRM-24 battery (don't know how old, we just bought the boat). I've heard you are supposed to buy 2 new batteries at the same time if you plan on installing 2 - is this true? And what type of battery would you recommend buying? Should I stay with the 24 group? Space is not an issue. We will be running a HDS-5 Combo (fish finder/gps) and a stereo, and whatever else draws power in the boat. I don't want to go overboard and waste money on batteries, I just want to know what to buy that's practical...

Thanks for your advice...
Desera

'98 Larson 206LXi
 

WyliePirate

Cadet
Joined
Aug 22, 2009
Messages
11
Re: Battery Switch and 2 Batteries...

Great question as I'm going to do the same thing very shortly. Will be watching this thread.
 

GXL205 Deke

Petty Officer 2nd Class
Joined
Mar 5, 2010
Messages
163
Re: Battery Switch and 2 Batteries...

Cool,

I just did the exact same thing last weekend. I am not aware of any rule saying you must buy the batteries at the same time, but one of these ole salts in here will probably advise to that, I am way to new to the boating scene to comment on that. This is my first boat, and bought it used the end of last Aug. But since my interstate battery was 2.5 yrs old and the only battery I had, I elected to get two new ones, and keep the interstate on a tender as a backup just in case type of thing. I wanted a big ole deep cycle to run all our toys and tunes when beached, and a strong starter battery to handle the cold cranking chores and be able to switch between them.

I have installed a Perko 8501DP Marine Battery switch, with a 1000 amp continental starter battery on "1" and deep cycle on "2". Came with a great diagram and instructions. It Looks great in my engine compartment and works great in all tests and I predict will be highly functional for what I wanted it for. Didn't want to get caught running down my 1 battery at the beach blowing up tubes and cranking out the tunes with the system in my boat. I installed it in the engine area so the kids [little] would not gravitate to it and start turning the knob back and forth.
 

DYLBOSS

Petty Officer 2nd Class
Joined
Aug 11, 2009
Messages
161
Re: Battery Switch and 2 Batteries...

I've been doing some searching on this forum for ideas as well. I'm getting ready to pull the trigger on this exact thing. I'm not an electrical genius either, so I'm curious to see what people are doing. I want to be able to charge both batteries at the same time when the engine is running too. I'm kind of confused at how to run all the wiring.
 

scutly

Petty Officer 1st Class
Joined
Aug 20, 2009
Messages
368
Re: Battery Switch and 2 Batteries...

i have two batteries now, but i spend all day switching back and forth from 1 to 2. i want this Blue Sea System

bluesea.jpg
 

GXL205 Deke

Petty Officer 2nd Class
Joined
Mar 5, 2010
Messages
163
Re: Battery Switch and 2 Batteries...

Understand! I am an electrical moron. Reputable Boat mechanic did mine, but like a said it had a great diagram and instructions, I just dont want to A. shock the crap out of myself, that sucks, and B. ruin something on my new boat. So I acquired the new battery tray, switch , and batteries and took it all to him and he had the marine battery cable in bulk, he charged me a modest fee to install. It tested well and he guarantee's his work for 180 days. So if its jacked up he will fixy. :D

The job was very professional..and I have 350 bucks in it total parts (including both batteries) and labor, keeping in mind this is a fancy setup for a 20' family lake runabout.
 

DYLBOSS

Petty Officer 2nd Class
Joined
Aug 11, 2009
Messages
161
Re: Battery Switch and 2 Batteries...

i have two batteries now, but i spend all day switching back and forth from 1 to 2. i want this Blue Sea System

Hmmmmmmm. I like that a lot. Looks like they dumb it down for the kindergarten installer. Perfect!
 

Silvertip

Supreme Mariner
Joined
Sep 22, 2003
Messages
28,758
Re: Battery Switch and 2 Batteries...

I did not see anything from any of the previous posters that would require any of you to absolutely need a dual battery setup or a switch. Unless you have a killer stereo system with high power amps, a trolling motor, electric anchors, or any other high current draw items you simply do not need a switch. Many folks use them incorrectly anyway. Here's the deal. First, you do not need two new batteries when you install a switch unless they are due for replacement anyway. What size battery you use depends on what you run off of them. Obviously battery capacity (amp/hrs or reserve minutes) is the measure of that. More is better. You cannot go too big with batteries -- just too small. The difference in price is rather insignificant. Next, if battery switch use confuses you, then opt for an ACR (automatic charge relay) or VSR (voltage sensing relay) both of which do the same thing in that one battery (usually the start battery) is designated the primary and only it will be charged until the trip point on the ACR/VSR is reached. At that point charging switches to the secondary or house battery. If you do insist on a switch, then get over the notion that some things get wired to the house battery and only the engine stays on the start battery. Both batteries get wired to the switch. Everything on the boat except an automatic bilge pump gets wired to the COM terminal on the switch. Then whatever battery (!, 2, or BOTH) is selected is what powers the loads and the engine. There is absolutely no reason to be constantly messing with the switch. Set it to BOTH and go. If you do happen to beach the boat or run a trolling motor for an extended periiod, THEN switch to the house battery to save the start battery. Simple as that.
 

GXL205 Deke

Petty Officer 2nd Class
Joined
Mar 5, 2010
Messages
163
Re: Battery Switch and 2 Batteries...

Killer Stereo here. And that is what I got it for. Beaching for extended stays, switch to house battery. Everything on mine is wired to com just like silvertip said.
 

rauch0812

Petty Officer 2nd Class
Joined
Feb 4, 2010
Messages
145
Re: Battery Switch and 2 Batteries...

Wow, so many responses it's overwhelming! We do not run any special high powered fancy anything, but we do plan on anchoring out and listening to the radio, blowin' up toys, etc for very long periods at a time and I'm just the kind of crazy lady that I'll drive my hubby crazy making him start the boat every 30 min to prove to me we're not stranded. See, a couple hundred will make me a happier person (which makes everybody happier!). So, I have three questions I'm trying to get answered:

1. We were going to install a perko switch for like $40 and I don't think I'm confused about the switch.. turn it to any single battery when we anchor out for the day - turn it back to both when we start her back up, right?

2. Can I grab another interstate SRM 24 (like I already have in the boat) for $75 at the dealer down the street or am I being too cheap? (apparently I'm currently running on one deep cycle battery as my only battery - guy at the battery store said that's fine)?

3. Can I use 2 different kinds of batteries on the switch (one deep cycle and one cranking) or should I just throw a second deep cycle on there and keep it simple?

Is this enough for the peace of mind I'm looking for?

Thanks,
Desera
 

salmonee

Chief Petty Officer
Joined
Jun 26, 2008
Messages
408
Re: Battery Switch and 2 Batteries...

I doing the same thing. I'm putting in two new batteries. Only b/c my previous is 5yr old. One deep cycle and one starting. I'm going to use the blue sea 6011 switch. Its a new one and very simple. One battery is strictly for the stereo/electronics and one is for the engine. Set the switch to combine when you run around to charge both. Very simple. By the way, don't forget the marine electrical wires, they are very expensive.
 

rauch0812

Petty Officer 2nd Class
Joined
Feb 4, 2010
Messages
145
Re: Battery Switch and 2 Batteries...

marine electrical wires? can you send me a link to what i need? I have a friend who is an electrician who will install this for me, but I'd like to gather everything before he goes out of his way to come over and put it in.
 

salmonee

Chief Petty Officer
Joined
Jun 26, 2008
Messages
408
Re: Battery Switch and 2 Batteries...

marine electrical wires? can you send me a link to what i need? I have a friend who is an electrician who will install this for me, but I'd like to gather everything before he goes out of his way to come over and put it in.


Your lucky I did all the work. No questions ask, best deal ever. See the custom build area.

http://shop.genuinedealz.com/
 

GXL205 Deke

Petty Officer 2nd Class
Joined
Mar 5, 2010
Messages
163
Re: Battery Switch and 2 Batteries...

Wow, so many responses it's overwhelming! We do not run any special high powered fancy anything, but we do plan on anchoring out and listening to the radio, blowin' up toys, etc for very long periods at a time and I'm just the kind of crazy lady that I'll drive my hubby crazy making him start the boat every 30 min to prove to me we're not stranded. See, a couple hundred will make me a happier person (which makes everybody happier!). So, I have three questions I'm trying to get answered:

1. We were going to install a perko switch for like $40 and I don't think I'm confused about the switch.. turn it to any single battery when we anchor out for the day - turn it back to both when we start her back up, right?

2. Can I grab another interstate SRM 24 (like I already have in the boat) for $75 at the dealer down the street or am I being too cheap? (apparently I'm currently running on one deep cycle battery as my only battery - guy at the battery store said that's fine)?

3. Can I use 2 different kinds of batteries on the switch (one deep cycle and one cranking) or should I just throw a second deep cycle on there and keep it simple?

Is this enough for the peace of mind I'm looking for?

Thanks,
Desera

Question 1. Yep that is what mine is for.
Question 2. Yes you can get another of what you have. But I have a starter for starting and a deep cycle for beaching
Question 3. I was advised yes and that what I did. see 2.

With all that said, if I had it to do over I would have listened to silvertip before taking the plunge. But the 2 battery Perko setup will work fine.
 

GXL205 Deke

Petty Officer 2nd Class
Joined
Mar 5, 2010
Messages
163
Re: Battery Switch and 2 Batteries...

Oh and this cat named "Bruceb58" on another post noted the following:

"I would just get identical deep cycle marines. The only case where I would get a dedicated start battery would be if you had fuel injection since they are not as tolerant of lower start voltage."

dont know if that is true, but glad I have a starter and a deep cycle on my perko in case it is true. Cuz I am multi-port fuel injected.
 

rauch0812

Petty Officer 2nd Class
Joined
Feb 4, 2010
Messages
145
Re: Battery Switch and 2 Batteries...

Ok, referring to Silvertips advice... there are two parts - the first part being I don't really need two batteries or the whole second part where I don't have a clue what he's talking about... which part are you referring that you wish you'd followed? Urgh... does it have something to do with the switch?

Also, sounds like I should just grab a cranking/starting battery to add to our set up... with one of each battery I would still operate the switch the same way? Put the deepcycle on 1 and use that when running accessories, then throw it back on "both" before we fire her up and take off?
 

GXL205 Deke

Petty Officer 2nd Class
Joined
Mar 5, 2010
Messages
163
Re: Battery Switch and 2 Batteries...

was talking about his second part. ;)

But yes that is all you would need. The additional marine cabling, a good starter battery, and the Perko. Voila!

I dont intend to use the both setting unless I need both to get her turned over because of a problem. It will be on my deep cycle for the tunes/beaching and on 1 when I am starting. My leaves the water at the conclusion of the day, so the charging happens on my battery tenders in my boat storage lock up.
 

WyliePirate

Cadet
Joined
Aug 22, 2009
Messages
11
Re: Battery Switch and 2 Batteries...

So GXL, if you had it to do it over, you'd just go with one big starting battery?
 
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