What is the Ideal Battery Charging System?

[Homeless_by_Cho]

I am a retired graduate mechanical engineer so I am not totally stupid about batteries but I have been reading many posts on this forum and I am completely overwhelmed and baffled. Specifically, I have been following the Amp hours to fully recharge? post on how to tell if your battery is fully charged. Since I didn't want to hijack their thread, I started this new one.

I am picking up my new truck camper in two weeks. I believe that it will have a 45 amp Progressive Dynamics converter charger. I need to wait and see what batteries it will have but most likely lead acid. I will be mainly dry camping. I will not have any solar. I have a 4 gauge wire in the truck from the positive and from the negative posts and will connect it to the truck camper battery terminals. I will have a Honda 2000i generator with me to use for the microwave and charging purposes.

Now what I would like to do is get the best charging system I can for it. My hope is that I could get a simple answer something like: Buy this “Brand and Model” charger and “Use it in this fashion.” I realize that is a very over-simplified request but it is a starting point for me. Once I have the correct charger, I can learn thru your help how to most efficiently maintain my battery system. I plan on using the camper’s converter charger to maintain the battery when in storage.

LeRoy

[HiTech]

Interesting. You can get low profile solar if you decide it would be handy.

Jim

[BFL13]

I would get a proper solar panel about 130w (8.2a Isc) and a simple 10a PWM controller and a bit of wire (long jumper cables work for that) and carry the panel on the camper's bed till you get somewhere and then prop it up outside facing the sun. Way too easy, gets lots of AH to help make up for running the fans all day in the summer.

[Homeless_by_Cho]

pianotuna wrote:
Hi,

Why are you solar resistant? *curious smile*

Thank you for your question. I am a full timer. My new truck camper will be my summer travelling house. I already own a Honda 2000i. I have no idea what roof area will be available on the camper. I will use the camper during June thru October mainly dry camping in remote areas. I am not "solar resistant" but I am being practical based on what I own, how I use it, and what roof area may or may not be available on the truck camper. I am concerned about roof top obstructions when backcountry camping. I did not order the camper with air conditioning because of overhead obstructions. Once I get the camper on May 27th, I will have a better idea of what real estate is available. I appreciate your input. By the way, I own a 5th wheel trailer that is my full time home in the south during November thru April.

LeRoy

[MEXICOWANDERER]

I will be mainly dry camping

How Often?

For What Period Of Time?

What is the BEST car, pickup, airline, political party, state, hamburger?

IMHO try something. If it doesn't work, go from there...

[pianotuna]

Hi,

Why are you solar resistant? *curious smile*

[Salvo]

Adding the word "ideal" to your question puts it into another class. If you are doing a lot of boondocking and need to run the gen, then the PD converter is not ideal. The PD is a crowd favorite, but isn't ideal. No one likes generators. You want minimal gen run times. That means getting a converter that charges batteries fast. You will also need to beef up the charging cable from batteries to converter. One key to fast charging is placing the converter close to batteries with big fat cables (2 gauge cable).

The first thing I would do is purchase a 100A shunt panel amp meter (from ebay) and measure charging current. Does charging current quickly decay? If yes, you got problems.

Sal

msiminoff wrote:

However, there is no one right answer to your question and the ideal charging system really depends upon how you intend to use your camper. Without a lot more information, it's pretty tough to say "Buy this charger and use it in this fashion”.
-Mark

[time2roll]

As long as you have a Honda 2000 and PD converter most of the issues are covered. I would just see how it goes for a bit before you start spending a bundle on improvements and gadgets. Worst case you will need new batteries in a year or two as you figure out what works best for your needs.

Be sure to read over in the Truck Camper forum as they have systems taylored to the limited space and needs etc specific to a TC.

[msiminoff]

Hi LeRoy,
Okay, but only since you specifically asked for it:
Buy a Xantrex TRUECharge2 60A (with control panel) and select the 3-stage charging profile. Select the battery type based on the battery chemistry. Be sure to use the battery temperature sensor.

However, there is no one right answer to your question and the ideal charging system really depends upon how you intend to use your camper. Without a lot more information, it's pretty tough to say "Buy this charger and use it in this fashion”.

If you are buying your camper new from Northern Lite, then you might as well have them install good quality batteries and proper charger right from the get-go... this means two group 31 deep-cycle (FLA or AGM, your choice) 12 volt batteries or a pair of 6V golf cart batteries.

- What is your dollar budget for batteries and charger?
- Have you done an anticipated power budget? How much power do you need? What is your highest planned current draw?
- What is the battery capacity in A/h?
- Will you be driving every day? If so you might consider a high current alternator as your primary charging source (you may need to go to 2ga or even 0ga wire instead of the 4ga if you're only making short trips)
- What's your aversion to solar?
- Will you have mains AC power available where you're camping or is your only source of AC the EU2000i? How long are you willing to run the generator every day?
- Do you need a high-current inverter too? If so you might consider an inverter/charger (e.g. magnum)

It is my opinion that the PD-45 will neither charge at high enough voltage nor for long enough time to bring the battery to 100% SOC every day.

Cheers
-Mark

[full_mosey]

BFL13 wrote:
IMO forget the expensive clamp meter for now anyway. The 10 amps feature on the cheapo multimeter is not required for most things, but is useful for the odd thing. You just want the voltmeter part for now.

You can use the 120v setting to check campground pedestals. You can use the DC voltage setting to check any thing in the RV that is 12v. eg, to see if the converter is working at 13.x v and you are not just on battery at 12.x volts with a duff converter.

While camping off grid you want to know when it is time to recharge. Your "morning voltage" before you turn on stuff will start at say 12.65, then next day it might be 12.45. You want to stay above 12.15.

So you see at that rate next day it will be 12.25. Hmmmm. Ok that means if you wait another day it will be 12.05, so you better recharge at 12.25 to stay above 12.15.

X2!

I am 100% AGM and had to learn to read battery health without a hydrometer.

I use BFL's technique as well to forecast when I need supplemental genny/shore-power charging. Of course, you must have enough AHs in your battery bank to last more than a day.

I have a meter called a Turnigy. It has a few extra features that make it better than a typical hand held meter(HHM).

One feature is that it shows the lowest voltage since attached. Low voltage can warn you if your circuit boards in your propane fridge might shut off soon. In my case, it warns me about my 12V fridges.

After I recharge I reset the Turnigy $30.

If placed in-line between a source and load, you can get Amp data such as accumulated AHs, Watthours, and Highest Amps.

HTH;
John

[BFL13]

IMO forget the expensive clamp meter for now anyway. The 10 amps feature on the cheapo multimeter is not required for most things, but is useful for the odd thing. You just want the voltmeter part for now.

You can use the 120v setting to check campground pedestals. You can use the DC voltage setting to check any thing in the RV that is 12v. eg, to see if the converter is working at 13.x v and you are not just on battery at 12.x volts with a duff converter.

While camping off grid you want to know when it is time to recharge. Your "morning voltage" before you turn on stuff will start at say 12.65, then next day it might be 12.45. You want to stay above 12.15.

So you see at that rate next day it will be 12.25. Hmmmm. Ok that means if you wait another day it will be 12.05, so you better recharge at 12.25 to stay above 12.15.

[Homeless_by_Cho]

Westend and others,

Sorry for being such a pain in the butt but I know just enough that I am totally dangerous and completely confused.

How will I use this meter? Do I record voltage first thing each morning and watch the trend? If it is staying at a certain level, ie 12.60 volts, then I am recharging OK? Or is there some other measurement that I should be monitoring and trending? And what about the AMP reading; what do I do with that? How is an AMP reading useful to me? Where do I take these readings? My objective is to get good life out of my batteries with reasonable maintenance. Initially, I am willing to put in time to determine my battery charging needs but, eventually, I only want to do a quick check each day to verify its condition and be done with them.

I looked at both the Sears and the Fluke websites and became totally confused. I understand that one of the features of the meter is a 12VDC display to two decimal places.
1) What does it need for DC amp range? 100 amp, 200 amp, 5 amp, 10 ma?
2) Should it be a clamp-on type meter?
3) What other features do I need?

I am going to Green Bay, WI on Wednesday and they have a fair size Sears store. Maybe I can pick up the proper meter. They also have a Harbor Freight store. Someone mentioned having one of their less expensive ones. Are the requirements of this multimeter the same as above?

Thanks,
LeRoy

[westend]

Forgot to mention, it's kind of practical to carry a cheap Harbor Freight meter or two and a test light along with a good multimeter. If your batteries fail in the main meter or you would like to measure at two points at once, the extra meters come in handy. The entry price is less than $10 for the HF meters.

Edit: BTW, received your PM but these Forums are possessed, it seems. I'm unable to read it. If your message wasn't too personal, you can relay it here.

[rexlion]

+1 for any model of Fluke meter.

[time2roll]

Try your best to avoid the hydrometer.