Charging Batteries with Perko Switch

[QC]

Re: Charging Batteries with Perko Switch

I do like Outsider and run a 1000 watt system. First run of the day I charge on Both, then Switch to 1 or 2. Odd for odd date, even for even date.

 

[wrench 3]

Re: Charging Batteries with Perko Switch

My house batteries have a much larger capacity than my starting battery (we are set up to run the fridge, water pump, lights and accessories for three days without recharging), so I can't interchange batteries. Also my battery switch is in the engine compartment under the rear deck, which makes switching on the fly rather inconvenient. So we start on the cranking battery and then switch to both batteries until we moor again.
However, if you have two identical dual purpose batteries, interchanging them sounds like a good idea.

 

[UncleWillie]

Re: Charging Batteries with Perko Switch

The bottom line in this whole discussion is that if your alternator has enough output to remain in regulation (13.8v or more), then combining the batteries during charging is a non-issue.
It is done all the time without any problems.

 

[wrench 3]

Re: Charging Batteries with Perko Switch

Well, I am with you on this one!
I am not quite sure what part you are disagreeing with.

A good battery will not take more charge than it can handle as long as you don't push more than 14.5 volts at it. A fully discharged battery has a high internal resistance and will therefore take less amperage until it gets rolling. If you put a fully discharged battery on an automatic charger it will mistake it for fully charged. You have to trickle charge it first.

 

[smokeonthewater]

Re: Charging Batteries with Perko Switch

the only time I ever have to fool with my battery switch is when I winterize the boat... I have 4 batteries and may add a fifth but my system is automatic.... If my starting batt fails I will have to switch to house batts but otherwise the system is always charged automatically.

both engines and genny start off of one starting batt and navigation systems run off it it as well. All other systems operate off of house batts...

 

[Home Cookin']

Re: Charging Batteries with Perko Switch

if you shouldn't charge them both at the same time, why ever run on "both"? I always go one or the other, but my batteries are the same and I don't run many electronics, or sit with the electronics on very long when the motor's not running.

 

[UncleWillie]

Re: Charging Batteries with Perko Switch

A good battery will not take more charge than it can handle as long as you don't push more than 14.5 volts at it. A fully discharged battery has a high internal resistance and will therefore take less amperage until it gets rolling. If you put a fully discharged battery on an automatic charger it will mistake it for fully charged. You have to trickle charge it first.

I hate to keep agreeing with you.:joyous:
It takes all the fun out of it!

And if you discharge the battery more than a very few times to the point that the charger gets confused;
The life of the battery is going to be severely compromised.

Don't take them below 11.5v and the issue will not come up.

 

[smokeonthewater]

Re: Charging Batteries with Perko Switch

there is no reason to not charge at the same time....

 

[Silvertip]

Re: Charging Batteries with Perko Switch

I grin when I see all this "switch fiddling" conversation. It simply is not necessary if one thinks like a traffic cop. Just ask yourself where you want the electricity to come from and go to? For example, first start of the day prior to making a long run to a fishing hole you have a number of options but the one that makes the most sense is switch from OFF to HOUSE (usually BAT 2). Start the engine and run to your honey hole. You kill the engine, fish for as long as you like (or run your high power electrics) since you are already on BAT 2. Time to go? Start the engine. NO! You don't need to switch to BAT 1 because BAT 2 likely has more than enough power to start the motor. It will also be charged during the run back to the dock or wherever you intend to go. IF and only IF the battery is flat and fails to start the engine would you need to switch to BAT 1. If you intend to make a series of frequent but short stops during the day start the day on BAT 1 and leave it there. Or start on BOTH and leave it there. You see -- it's really not that difficult if you act as a traffic cop. The net result is that if you figure out how you intend to operate the boat that day, you don't need to be a "switch fiddler".

 

[caken]

Re: Charging Batteries with Perko Switch

All of your suggestions are great but also seem like personal preference. Because we all use our boats for different things operating our switches must be tailored to that and there is no wrong or right way. My initial question however was not about how to operate my switch but to more understand how the alternator charges the batteries when there are 2 connected in parallel with the switch. I am more interested in the electrical current part of it and why one battery can be so low and they equal out eventually. This is the stuff I never had a clear understanding of but definitely do now. Thanks everyone!

 

[wrench 3]

Re: Charging Batteries with Perko Switch

I hate to keep agreeing with you.:joyous:
It takes all the fun out of it!

And if you discharge the battery more than a very few times to the point that the charger gets confused;
The life of the battery is going to be severely compromised.

Don't take them below 11.5v and the issue will not come up.

I guess it,s all in how you phrase it. Sorry that you didn't have much fun, but I enjoyed it.
The first time I heard you shouldn't deep discharge a deep cycle battery I was quite surprised. Before that I thought that was what a deep cycle was all about.

silvertip: I run and start most of the time on both batteries. Switch to #2 if we're stopped for a long time. I usually do a cold start on #1 just to make sure it will still work if I need it.

 

[dingbat]

Re: Charging Batteries with Perko Switch

I got tired of playing the switch game and installed an ACR. I turn the switch on when I get to the boat and turn it off when I leave. Can't get any simpler than that.

 

[caken]

Re: Charging Batteries with Perko Switch

Another question related to the switch and charging the batteries.....Right now we have a group 24 starting battery and we are looking to upgrade our deep cycle. Is there an issue with putting in a group 27 or 29 deep cycle and keeping the group 24 starting or do we have to upgrade both to the same group size?

 

[Don S]

Re: Charging Batteries with Perko Switch

Another question related to the switch and charging the batteries.....Right now we have a group 24 starting battery and we are looking to upgrade our deep cycle. Is there an issue with putting in a group 27 or 29 deep cycle and keeping the group 24 starting or do we have to upgrade both to the same group size?

There is no reason to have both the house and starting batteries the same. Here is a thread (with some diagrams) of using 3 batteries for the house battery, and a single starting battery.

http://forums.iboats.com/electrical...tors/turning-2-battery-system-4-a-592106.html

 

[Silvertip]

Re: Charging Batteries with Perko Switch

No.

 

[smokeonthewater]

Re: Charging Batteries with Perko Switch

I have a single group 24 tart batt for all engines and 3 group 31 house batts... all of em charge at the same time with no issues at all

Dingbat, is it just me or does reading about all of this switch flipping wear you out too LOL

 

[UncleWillie]

Re: Charging Batteries with Perko Switch

...There is no reason to have both the house and starting batteries the same...

+1
As long as the charging system is up to the task;
You can charge a Motorcycle Battery in Parallel with a Truck Battery and they will both charge as if the other one didn't exist.

 

[dingbat]

Re: Charging Batteries with Perko Switch

Dingbat, is it just me or does reading about all of this switch flipping wear you out too LOL

Some can over complicate a bowel movement..... lol

 

[caken]

Re: Charging Batteries with Perko Switch

Ok, update to my previous question.

We were upgrading our batteries and wiring over the weekend and noticed that we have a Charles Marine Battery Isolator installed in addition to a perko switch. This is the first time we have seen this and now want to find out what is the best option moving forward.

I am very familiar with the perko setup (wiring and how to use) but I have never had an isolator in a boat before. Right now this is how it is set up...

Alternator to isolator, 2 wires from isolator to 1 and 2 post on switch, and then 1 and 2 post on switch to 1 and 2 battery. All other wires including the starter and house accessories off the common post of the perko.

My questions are would it be better to remove the switch all together and just use the isolator? Or keep the switch and remove the isolator? Or, should we look into upgrading to a new ACR and remove the isolator and switch? Sorry for all the questions, just want the best way to have the 2 battery setup so that we can drain the house if needed and keep the starting charged.

 

[Don S]

Re: Charging Batteries with Perko Switch

Personally, I think the best way is with the Bluesea add-a-battery setup.
All you do at the beginning of the day is turn the switch to on. Have fun, kill your house battery if you want. The starting battery will not be touched. Start the engine, and the charging begins.
End of day turn off. No playing with which battery am I on, or should I be on right now.
Isolators also cost you almost a full volt from charging to max capacity.

More info. http://www.bluesea.com/products/7650/Add-A-Battery_-_120A