Community Forums

camaraderie · 12-08-2013, 06:03 PM

I'll second Matts recommendation on IOTA as making a great, reliable, PROPER charger (with the SMART IQ4 module) for deep cycle systems. If you've got a bit AGM bank it is particularly of interest since you can charge at a much higher rate and the IOTA units can even be daisy chained to deliver higher outputs if needed. May I suggest that you look around on line a bit for one rather than buying from the RV store...$$ can be saved! Do NOT buy or use these units without a built in or add on IQ4 module!

mr300ce · 12-11-2013, 10:22 AM

Thanks for all the informative and reminding (ly) replies. I knew all that stuff 3 yrs ago when I researched it then, but had stuffed it WAY back in my mind.
I did go out to the MH and found the owner's binder, and found that the charger is a Magna-Tek 950....

It says it is a 50amp, and that it is designed to run all my 12v stuff and NOT over-charge the batteries. I do have some 4yr old Trojan T105 batteries that have been kept topped up from either shore power, or the 2-3ft, 15w solar panel. Stored here in the desert, even getting down to 15*F at night, when I look at the voltage about 10am, with the solar panel plugged in, it says 12.7v (13.5v in the summer). I believe the batteries are OK.

I now believe the batts got low because I was camping for a week, and not running the generator long enough (1-2hrs morning, 1-2hrs night) to bring them back up.

I will (next dry camp) run the generator long enough to bring them back up.

Shadowcatche · 12-12-2013, 03:21 AM

Magnatec converters are trouble prone to begin with (do a search on Magnitec) and yours may be old enough to be single stage. What voltage is it putting out at the battery when you first start your generator? As one reply indicated it should be in the 14+volts range and if not you are probably never reaching full charge particularly if the solar controller is not getting up into bulk charge range.

spritz · 12-12-2013, 08:13 PM

We decided to take the Optima 75 25 out of the 64 and use that for now. It just sits there til spring any how.

Davdeb1 · 12-12-2013, 08:38 PM

I bought 4 new t-105s in June. I also purchased a Iq4 smart controller for my IOS converter. Since I started boondocking, its been taking a very long time to recharge to 100%. I've checked the specific gravity, all cells are 1.275 or over. I have 450 amp hour of battery and the converter is 45 amp. It takes the batteries to 90-92 in 6-7 hours, but then takes another 6 days to get back to 100. I'm starting to doubt the readings from my trimetric meter.

Dunner · 12-12-2013, 09:18 PM

You might want to stop the charge when you think the batteries are full, let them rest over-night and check the gravity. If full, re-calibrate your Trimetric to tell it when they're really full.

Davdeb1 · 12-12-2013, 09:22 PM

Quote:

Originally Posted by Dunner

You might want to stop the charge when you think the batteries are full, let them rest over-night and check the gravity. If full, re-calibrate your Trimetric to tell it when it's really full.

I never thought about recalibrating. We are fulltime, so its almost impossible to rest batteries. I wonder if I used the battery shut off switch I could still get 12v power from the converter?

Dunner · 12-13-2013, 12:18 AM

Haven noticed lately, but I think mine still charges with the shut off switch in the off position either on shore or generator.

spritz · 12-13-2013, 07:00 PM

Quote:

Originally Posted by spritz

We decided to take the Optima 75 25 out of the 64 and use that for now. It just sits there til spring any how.

Just got done installing the battery out of the 64, into the 82 PA. OPTIMA 800 CCA Fired right up. Let the MH run 45 minutes. I have SP and am @ the S&B. One more thing done before the trip.
Tim

MattC · 12-14-2013, 12:55 PM

Quote:

Originally Posted by Davdeb1

I bought 4 new t-105s in June. I also purchased a Iq4 smart controller for my IOS converter. Since I started boondocking, its been taking a very long time to recharge to 100%. I've checked the specific gravity, all cells are 1.275 or over. I have 450 amp hour of battery and the converter is 45 amp. It takes the batteries to 90-92 in 6-7 hours, but then takes another 6 days to get back to 100. I'm starting to doubt the readings from my trimetric meter.

Dave,

If the hydrometer or refractometer (better) is a good one, believe it. But what you are seeing is a real issue with Lead/Acid Flooded Cell banks. The problem simply is that the electrolyte in the cells has to circulate to get where it really needs to be during the later part of the recharge cycle. The only thing to move it is density (and a little bit of heat). With things matched right, you can get to ~90% in 4~5hrs, but the last 10% can easily take 12 more hours.

Recalibrating the Trimetric will only help you to feel good about a bad situation. If the Trimeteric says it does get back to 100% (even in six days), then don't recalibrate it.

If you don't know about batteries, there are lots of places to learn more.

This is just exactly the work that I did on performance cruisers (sail yachts) before the depression.

Matt

BendOR · 12-14-2013, 01:09 PM

mr300ce-

Either of these 2 chargers will do well until you can replace that obsolete converter:

Black and Decker VEC1093DBD
Peak PKC0CV

Good luck!

mr300ce · 12-22-2013, 10:06 PM

OK.... so I have determined that the on-board Magnetec 950a is a 50amp, and charges the batteries OK, and trickles down to a maintenance charge when the batteries reach full charge. So I will leave that alone....for now.

BUT.... Last year I got one of those Harbor Freight 15w solar panels. That means it is only putting out about 1amp. Sitting in the sun during storage it does top up the batteries. But I am considering getting their 45w, (3x15w) panels. That would put out about 4amps.

What do you all think, as far as using them when dry camping to put some charge into the batteries while I am away being a tourist. Would that small amount be worth the $105 they would cost me (special coupons).
Solar Panel Kit - Save on this 45 Watt Solar Panel Kit

Looking to NOT run the generator 5hrs a day.

Shadowcatche · 12-23-2013, 05:11 AM

I am a HF fan for a number of things but solar is not one of them. What you are looking for is dollars per watt and if it is much more than $1 you are paying too much. Get a 50 to 100W panel (I found our 185W on Ebay) and a Morningstar SunSaver controller and wire it with large enough wire to keep voltage drop to 2%. From my stock RV answer files (saves my rather glacial paced keyboarding speed. Size a battery bank and PV array properly Rule of thumb SWAG (scientific wild ass guess), about 75 to 130 watts of panel for every 100 AH of house battery, or about one watt per AH that you have. Nothing substitutes for knowing your actual needs or wants (not necessarily the same thing). Know the actual measured loads and do the math. After 1 year of service (and maybe not even then), it is NOT advisable to enlarge a battery bank by adding new batteries to it, because a batteries voltage response changes with age. Internal resistance changes causing losses and failure to equalize. A weak cell will "steal" from the surrounding cells. The battery “chain” is only as strong as its weakest link). Solar if it is the primary energy source, should be sized to produce more energy than the load requires, that stormy day, shady camp site, solar charging battery loss thing. Buy high-quality batteries, you get what you pay for. Good deep-cycle batteries can be expected to last for 5 to 15 years, and sometimes more particularly with proper care and feeding. Cheap batteries can fail in half that time, and good batteries can fail with poor care and feeding. 6V batteries are not better than a good quality 12V (but may be easier to lift). The ideal battery bank is the simplest, consisting of a single series of cells that are sized for the job. Fewer cells will reduce the chance of defects (parts left out don’t go wrong). According to the Concord/Lifeline battery company based on their research you can mix battery sizes but not age and type i.e. AGM to AGM is OK AGM to Wet Cell is not, (lower internal resistance in AGM). When wiring a battery bank the goal is to maintain all of the cells at an equal state of charge. Cells that receive less charge are likely to fail prematurely. This can take years off of the life of the battery bank. A fraction of an ohm of added resistance in one battery string can reduce the life of the entire string. (1) Connect the two main cables to opposite corners of the battery bank, and maintain symmetry in wire size and lengths. This will help to distribute current evenly through the bank. 2) Arrange batteries to maintain even temperature distribution throughout the bank. Avoid uneven exposure to heat sources. Leave at least 1/2 inch of air space around each battery, to promote even cooling. (3) Apply a finish charge at least every 3 weeks (bring every cell to 100% charge). Use temperature compensation When batteries are cold, they require an increase in the charge voltage limit, in order to reach full charge. When they are warm, they require a reduction in the voltage limit in order to prevent overcharge. Bring the batteries to a full state-of-charge (SOC) at least every 3 weeks. This reduces internal corrosion and degradation, and helps to insure equalization, so that any weaker cells do not fall continually farther behind. Install a System Monitor Would you drive a car with no dashboard? Metering is not just "bells and whistles". It is necessary to help you to read the status of the system. Many charge controllers have indicator lights and readouts built-in. Their effectiveness for the most part very from creating false security with essentially meaningless ‘idiot lights’ to it gives “some” idea of what is happening. They are not a substitute for a system that actually measures what goes into and comes out of your battery(s) using a shunt. Two well respected systems Victron http://www.victronenergy.com/battery-monitor and the Trimetric from Bogart Engineering | manufacturer of the TriMetric battery monitor which measures volts, amps and amp-hours for battery systems

Davdeb1 · 12-23-2013, 08:47 PM

Quote:

Originally Posted by MattC

Dave, If the hydrometer or refractometer (better) is a good one, believe it. But what you are seeing is a real issue with Lead/Acid Flooded Cell banks. The problem simply is that the electrolyte in the cells has to circulate to get where it really needs to be during the later part of the recharge cycle. The only thing to move it is density (and a little bit of heat). With things matched right, you can get to ~90% in 4~5hrs, but the last 10% can easily take 12 more hours. Recalibrating the Trimetric will only help you to feel good about a bad situation. If the Trimeteric says it does get back to 100% (even in six days), then don't recalibrate it. If you don't know about batteries, there are lots of places to learn more. This is just exactly the work that I did on performance cruisers (sail yachts) before the depression. Matt

Thanks Matt, I just thought it was something I was doing wrong. I may have made a mistake by adding mineral oil to the batteries. The mineral oil does not allow the cheap hydrometer to work very well.

According to my Trimetric, after 5 or 6 days my state of charge finally gets a couple of amps over full. If this is how long it takes, I am ok with that and will defer to your knowledge and experience.