Onbaord Battery Chargers

[Sam]

I am going to be getting an onboard battery charger for Christmas so I went to BPS and viewed their options.

I need a three (3) bank charger and the BPS charger is a 5/5/5 amps model.

The BPS two (2) bank charger is a 10/10 amp option.

I will be using the "gel" type batteries when I replace the trolling motor batteries this summer so please include the "gel" trolling motor batteries in the equation.

I need your input on:

1.  Bypass these two chargers and go with another brand?

2.  Go with the 10 amps per each of the two banks for the two trolling motor batteries and continue to use my marine charger for the cranking battery?

Thanks to all for your input and experience with onboard battery chargers.

[HPBB]

I have one of those BPS 5/5/5 chargers and it was the best thing I ever bought. I run 36 volt trolling motor and have 3 spiral cell batteries. I have been using the charger for 3 years now and have no problems. I use my boat alot, fish 20 tournaments or so a year and fish every weekend. when I park the boat next to the house i plug it in and don't inplug till I am ready to leave again and the batteries are alway ready. This charger has never let me down.

Jim

[Al Wolbach]

I'm not sure the 3 bank charger will work for you assuming you are using a regular lead acid battery for your cranking battery. I don't believe, once the charger is set for AGM batteries, that it will fully charge your cranking battery. You may be better off with a 2 bank and charge your cranking battery with another charger as needed.

Way2Slow can probably respond with accurate info. He has helped many with his battery advise............................Al

[George Welcome]

If you need a charger get the best:

http://www.marinco.com/scpt/brandSearches.php?currentMarketName=Guest%20Recreational&currentSection=Trolling%20Motor%20Chargers&currentSubsection=Triple%20Battery%20Applications

You cannot beat or compete against a Guest Charger

[DEISWERTH]

Way2slow will tell you exactly what you should do, he has helped me alot!

Doug

[Way2slow]

Gee thanks folks, ya'll make it sound like I'm suppose to know something about this junk. Boy, have I got ya'll fooled.

Anyway, here's my two cents worth.

First, I would not run Gel batteries, they have the lowest amp hour capacity of any battery you can buy and cost much more. Amp hour capacity (or reserve minutes if Ah is not stated) is what determines how long the battery will run under a given load.

Second, most onboard chargers are going to tell you to use the same type batteries on each bank. Meaning if you run Gel TM batteries you will need a Gel cranking and not sure they even make one. The next solution would be to have an onboard just for the Gel TM batteries and another just for the cranking battery. You are also going to run into this same problem if you run AGM batteries.

Usually when you set the charge for Gel or AGM it sets the whole charge and not just the banks you want to use for that purpose. There is a big difference in the way a charger charges those batteries over the way it charges flooded lead cell batteries.

When you charge a flooded cell battery with a charge set up for them, the voltages may go over 15 volts and the current is controlled, not the voltage. That voltage would destroy a Gel or AGM in a short time. They are never to be charged at a voltage greater than 14.4 - 14.6 volts.  14.6 is an equalize voltage and a lot of batteries don't recommend you equalize their AGM's. When you set the change the program in the charger for Gel and AGM, you change it to a controlled voltage charge so it does not let the voltage get over 14.4 volts. Then you have the float voltage that changes. AGM batteries use a float voltage of 13.6 volts, Gel and Flooded cell batteries use a float voltage of approx 13.2 volts. So, you see, when you start trying to mix batteries on one charger, you create all kinds of problems.

As for Brand names, get what you think is best. I personnaly buy only ProMariner built onboard (they build your BPS and Cabela's brands) chargers. Their three stage, on demand charging system will out charge any competitors with a similar rating, bar none. A three bank, 6 amp per bank, becomes a 9 amp per bank to the TM batteries as soon as the cranking battery is charged, which is usually pretty quick. Their's also goes into a float mode, many others cut off and cut back on at a preset level as the battery discharges, something I don't care for at all.

[Sam]

Thanks a million, Way2Slow.

I am going to save this thread and then use it to purchase the onboard charger.

I will also purchase regular batteries and not the gel type.

You guys are the best.

[sodaksker]

Their's also goes into a float mode, many others cut off and cut back on at a preset level as the battery discharges, something I don't care for at all.

2slow,

curious as to why you don't like this feature?

[Way2slow]

When a battery is maintained by the proper float voltage there is absolutely no chance for it to sulphate.

I also don't care for charging a battery that has greater than 80% charge and to prevent sulphation, this would be necessary. If the battery is allowed to sit for any length of time at less than 80% charge it will sulphate very quickly. Some chargers require a full one volt drop before they turn back on, I just feel this leads to the chance of sulftation, The number one cause of marine battery failures.

Keep in mind, I'm not a battery engineer, but think I'm a little smarter than the average bear when it comes to dealing with them and this is just my own view points.

[sodaksker]

What is "sulphate" or what does it mean for a battery to " sulphate"?  

Last year I bought one of the bps xps triple bank chargers.  You are supposed to leave it plugged in all the time.  It goes into a float mode after batteries are fully charged, then comes back on once the batteries drop.  If I run my tm for about a minute it will come back on to charge.  I don't know what the setpoint is for the amount of drop it takes to put it in to "charge" mode again but, it does not seem like much.

The reason I bring this up is that I noticed that my tm batteries were not holding much charge by August.  I checked the batteries and they were both very low on water.  I'm wondering if my new battery charger had any part in this.  I have since bought new batteries and they have been sitting plugged in on the charger for the last 6 weeks and will probably remain there til march.  

Should I unplug them for the winter?

[Way2slow]

Sulphating in a simple term.  Battery acid (electrolite) is a solution of sulpuric acid, when the battery sits at a discharged state, the sulpher will crystilize on the plates in the battery.   As this happens that area can no longer transfer electrons, reducing the amp hour capacity of the battery.  This means that if you run 8 hours on a new 120 Ah battery, then 50% of the plate area is sulphated, you can only run 4 hours.

Batteries loose water, unless you get an AGM or Gel.  Part of proper battery maintenace is keeping it filled with distilled water, keeping it clean and dry and all cables connected cleaned and some type of Battery Saver on the terminals.  You can't just throw them in the back, connect a charger to them and forget about them.

Yes, you should leave the charger plugged in 24/7 when the boat is not in use.

Your BPS charger does go into a float mode.  This is a constant voltage of approx 13.2 volts the whole time the charger is on.  It does not let the voltage drop and then turn back on at a set level.  

As for the charge causing damage to your batteries, the lack of maintaining proper water level killed them.  Because a battery is maintained at a full charge state, they do tend to use more water than a battery that is not connected to and onboard charger, so you should check water levels once a month.

[sodaksker]

2slow,

Thanks for the info.

What causes your battery to lose water if your charger is working correctly?

[George Welcome]

Another battery information source:

http://www.uuhome.de/william.darden/

[Way2slow]

Evaporation, and since the charger is maintaining a little more heat than a battery just sitting, it evaporates a little quicker

The site that George Welcome posted is a good source of info. I've also posted several other very good sites but they seem to draw little interest.

Read and understand that one and this one and you can be a battery gurru.

http://www.marine-electronics.net/techarticle/battery_faq/b_faq.htm#6

[sodaksker]

Thanks for the help guys.

It is greatly appreciated

[Pa Angler]

I have a 20 amp 2 bank Dual Pro SE on my boat and it works really well and I'm gald I got it Because I don't have to pull the batteries and I'm running 2 group 29's batteries and there's some weight there.

Chow