help with installing second battery

[cdrymalla]

ACR/VSR/combiner-separators or whatever you want to label them are generally misunderstood. There is lots of misinformation on this subject as well. It is precisely a depleted battery after a long duration at rest in combination with a large stereo and continued play that will bounce a voltage sensing solenoid back open after a trial and a failed attempt to close. While these are certainly convenient and can serve to protect your alternator, ACR/VSRs also can increase your dependency on AC shore charging. There is a ratio between alternator capacity, collective amp/hour reserves plus audio system wattage and current draw that will dictate the right scheme for a particular boat. One size does not fit all.
Yes, a properly wired and set Perko switch will always charge both batteries when underway.

David
Earmark Marine

So with the perko switch, is there no harm in connecting two differnt batteries (i.e., brand, condition, etc) to each of the banks and running in "both" mode so that the alternator charges the two batteries in parallel? Again, my concern is combining two different batteries (i.e., brand, condition, etc) ...

Further, lets say you run your stereo off of battery #2 only (using the perko switch) while the boat is off, and you deplete the battery #2, I understand that you can swap over to battery #1 to start the boat, but then you are running the boat without charging #2 (and from what I understand you do not want to change the perko switch settings (e.g. from #1 to both) while the boat is running). So to charge the #2 battery once started, it is my understanding that you would have to start in "both" mode. If this is correct, would the depleted battery #2 have a negative impact on starting the boat when #1 and #2 are combined; or will the power of the battery #1 (assuming it is charged enough to start if used by itself) be sufficient.

Essentially, I don't run the stero much, but when I do, I would like to make sure I have the first battery in reserve, and further, I would like to have a way to recharge the depelted battery while on the water.


Thanks in advance.

[Chexi]

This does not answer your question, but the setup I used to have and will be installing in my new boat had 2 blue tops and a blueseas isolator/combiner relay with a manual combiner switch. I also used a CTEK charger with 2 comfort LED indicator quick connects on the batteries. It does not charge them both at the same time, but I found that my main battery always stayed charged in this setup anyway from running the boat and only the audio battery really ever needed shore charging.

[wake_fun]

So with the perko switch, is there no harm in connecting two differnt batteries (i.e., brand, condition, etc) to each of the banks and running in "both" mode so that the alternator charges the two batteries in parallel? Again, my concern is combining two different batteries (i.e., brand, condition, etc) ...

Further, lets say you run your stereo off of battery #2 only (using the perko switch) while the boat is off, and you deplete the battery #2, I understand that you can swap over to battery #1 to start the boat, but then you are running the boat without charging #2 (and from what I understand you do not want to change the perko switch settings (e.g. from #1 to both) while the boat is running). So to charge the #2 battery once started, it is my understanding that you would have to start in "both" mode. If this is correct, would the depleted battery #2 have a negative impact on starting the boat when #1 and #2 are combined; or will the power of the battery #1 (assuming it is charged enough to start if used by itself) be sufficient.

Essentially, I don't run the stero much, but when I do, I would like to make sure I have the first battery in reserve, and further, I would like to have a way to recharge the depelted battery while on the water.


Thanks in advance.

I have mine setup just like you said. All stereo wiring goes to 2nd battery (I've never drained that battery down). I switch from 1 or 2 to both while underway. You just DON'T turn the dial past the OFF to do it.

[cdrymalla]

I have mine setup just like you said. All stereo wiring goes to 2nd battery (I've never drained that battery down). I switch from 1 or 2 to both while underway. You just DON'T turn the dial past the OFF to do it.

Good to know that works...That would make it pretty simple to setup.

I also like the way Chexi mentions setting it up, but it seems I would still need to isolate the batteries from one another for shore charging.

I drew up a few diagrams the other day and I had a couple of ways to go about it that would make use of the surepower, allow use of a perko to swap to the 2nd battery for staing if needed. I wil try to post them and get your feedback.

Thanks!

[Chexi]

Yes, with my way you do isolate while charging, but only because my charger is only a 1 battery charger. CTEK makes another model that can do 2 at a time, it just cost about 3x. I think you could use it and just turn the manual switch to combine if you wanted to charge both at once.

[ski4evr]

I have the perko connected to two batteries like you have spoken of, and switch between the batteries at will depending on the situation to charge a dead battery or to cycle the use of them. The boat runs off the same battery for stereo and running alike. I usually switch between the two from saturday to sunday. Also, I connect the battery tender to both at the same time with the switch in 1+2. It is still a 12 volt system and just takes the charger longer to reach storage level (full charge). Worked all season without a hitch last year.

[cdrymalla]

I have the perko connected to two batteries like you have spoken of, and switch between the batteries at will depending on the situation to charge a dead battery or to cycle the use of them. The boat runs off the same battery for stereo and running alike. I usually switch between the two from saturday to sunday. Also, I connect the battery tender to both at the same time with the switch in 1+2. It is still a 12 volt system and just takes the charger longer to reach storage level (full charge). Worked all season without a hitch last year.

Also good to hear that swapping the perko switch while undrway seems to work fine.

With the C-tek 7002 I have, I plan to seperate each battery while charging (as Chexi mentions) so the charger has the ability to condition each one individually. So far, I have been pleased how the charger maintains/conditions a single battery. I just leave it plugged in and let it do its thing on the blue-top.

[EchoLodge]

Cheap Option

If you are running two batts that are identical you can also go with a continuous duty solenoid. When the engine is on it joins the batts. When it is off it separates them. I had this set up in my 90 sport for a decade. I plan on setting it up in my new boat this weekend. Makes it idiot prof as you do not need to worry about remembering to change the switch.

Looks like this!

http://www.go2marine.com/category.do...=grid&mfrno=84