Battery bank not holding charge--Please help!!

meghammock · January 2011

First off, greetings from Evington, Virginia!

Secondly, my hubby and I had a solar energy system hooked up to our camper (that we live in full-time) about a month ago. Yippie-ki-yay!
Problem is, the battery bank will NOT hold a charge! Everything works great and we have all the power we could need during the day, no issues, but as soon as the night rolls around, it's like we don't even have a battery bank. We got lucky the night the batteries lasted for 2 hours.
The company has been to our place trying to figure out why has not been able to come up with a solution.. They've tried passing band-aids (giving us a battery charger which we'd STILL have to run a generator EVERY DAY for) but we have not gotten a reason or solution to this problem!

They have supposedly set numerous systems up before and know what they're doing, and I've asked that they run numerous tests, and they say every individual component is in correct working order..
But they will come during the day, charge the battery bank, not even hook it up to the camper, and the batteries are STILL drained by the time we get home from work! Seems like we're only getting power from the panels/daylight.. The batteries just do not hold anything!

Does anyone have any clue why this could be happening?? I'll include the specs and a crappy diagram attachment of set up to hopefully help.. We're having to pay $20 a day in gas to run the camper off of the generator for power.. It's eaten up the money to feed my horsies, and I've pretty much given up hope of the company finding the answer (although I'll keep lighting fires under their hineys 'till we have one!)..
Thank you all SO MUCH in advance for any ideas you might have! We didn't drop all this money to have NO heat or power in the winter!! (heat is propane, btw)

PANELS are GE.
o 173 Watts
o 25.1 rated current
o 32.2 volts open current
o 7.5 short circuit current (amps)
o He said they have the controller set to where the panels are only sending 14.something volts to the inverter—Still higher than the 12 volt measurement of the inverter. See orange inverter and controller notes for more info tied to this.

BATTERIES are Rayovac UltraPro.
o 4 batteries at 6 volts each
o 20 amp hour capacity (had the number 215 under it, whatever that means)
o Mins. (minutes?) @ 75 amps (had number 105 under it, whatever that means)
o Hooked up in parrallel AND series configurations, so it is, according to them, a 12 volt, 200 amp system.

INVERTER is Durafied—8300DI (serial number, I think)
o 3000 watts, 6000 at peak
o 12 DC
o 115 AC
o He said that a 12 volt inverter is meant to take in 12 volts minimum but can take more than that, which is why he said the panels are set to 14.something volts through the controller. He said this would allow them to pull more power in to the inverter.

CHARGE CONTROLLER is Morning Star.
o I asked if the voltage of the panels was a bit much for a 12 volt inverter and he said that the charge controller is set to bring everything down to work correctly with each other.
o He said the controller is putting 40 amps in to the batteries.

niel · January 2011

Re: Battery bank not holding charge--Please help!!

just for clarification which morningstar controller do you have and how many pvs do you have and it's model number if you have that?

also be advised that leaving the inverter on even though there aren't any loads on it will drain the batteries for the inverter needs power in standby.

meghammock · January 2011

Re: Battery bank not holding charge--Please help!!

Good question--I'll see if I can take a look at the controller tonight:) There are 4 PV's, and I'll jot their model number down tonight!
Thank you so much for replying so quickly! A glimmer of hope!

mike95490 · January 2011

Re: Battery bank not holding charge--Please help!!

Sounds like your batteries are spec'ed for being a Starter battery, and not suitable for deep cycle. After a couple days of deep cycles, they are dead. Toast. Kaput.

With 40A of charge current, I would expect you would have 300 - 400AH total battery capacity, or about 4, 6 volt golf cart batteries, of about 100 ah each.

Running the vehicle engine is a VERY wastefull way to recharge, get a small 1,000 -2,000w size inverter generator (Honda EU 2000 as example) to run your backup battery charger.

i'm suspicious of your panels not producing the proper amount of power, your note indicates they are 30V and you would need a MPPT type of controller to down convert to a 12V battery.

Another problem, is your inverter, which to deliver 2,000W for your microwave, would need to pull 166A from the batteries, which is beyond their capacity, voltage will sag, and inverter will shutdown. Do you know if it is a pure sine, or mod sine inverter and did the sales man explain the advantages and disadvantages of each ?

Cariboocoot · January 2011

Re: Battery bank not holding charge--Please help!!

What I'm seeing (and part of it is guess-work) is:

Panels: 173 Watts * 4 panels = 692 Watts total. @ 77% efficiency = 532 Watts. @ 14.2 Volts charging = 37.5 Amps peak current.

Batteries: 4 apparently 215 Amp hour (at the 20 hour rate - standard) at 6 Volts = 430 Amp hours @ 12 Volts. This should supply up to 2.5 kW hours at a maximum 50% discharge. That's a lot of power available, but it is possible to exceed this.

Those panels should be able to charge those batteries. The question would be is the charge controller up to it? If it is an MPPT type like this one http://www.solar-electric.com/motr45ampmps.html it should work. If it's the PWM version, a significant part of the power the panels are capable of won't be harvested.

I can almost guarantee that inverter is a MSW unit, so many loads you have will be using somewhat more power than they would on a pure sine wave inverter. I doubt that's the trouble, though.

If the controller is right, I'd look at the wiring. Specifically how the batteries are wired and the quality of the connections and sizing. You can lose a lot of power to bad wiring. And like Mike said, if the batteries have been killed (or are old) they're not going to have much capacity left.

I'd be a bit leery of any "expert" who thinks you could connect those batteries in parallel/serial and get 12 Volt at 200 Amp hours. Either the battery rating is wrong or they're talking about usable Amp hours or they can't do math. (That last one is very common and occasionally afflicts even the better educated moguls around here.

)

meghammock · January 2011

Re: Battery bank not holding charge--Please help!!

I did ask if it was mod sine or true sine--He was really vague in his reply but made it sound like true sine.. Though I have my doubts. All's he said was I could charge my phones, computers, etc., but I get the impression he'd be fine with us doing that off a mod sine. I should have been less trusting in the start--From the looks of it, they gave us all poor quality components, although that may have been all we could afford.. Either way, I only know that true sine is better for more "sensitive" electronics and generates less of a buzz from the smoothness of the current.. Or something like that

Do you think we'd be better off getting our own deep cycle batteries? I think we have access to deep cycle go-cart ones, or are those kinda cruddy for this?
You're right about them being 4, 6v. They did load tests and supposedly checked each cell individually, and claim there are no problems with the batteries. Is there any way for us to test them ourselves? Seems like they charge them THEN test them.. Of course it's going to look good immediately after a charge and no use..

What is an MPPT controller? They say they've talked to the manufacturers and are sure they got the right kind, but I'm very curious about all the details.. And whether or not they are correct.

We do use a generator for our backup power and for powering the battery charger.. It's a Honda 5000 w one and friggin' loud as a freight train (which is not so bad when it drowns out those darned fighting owls....).. I may have misunderstood what you meant by that though?

Thank you so so much.. I can't wait 'till this is all straightened out.. I'm looking at our type of controller and panel specs and whatnots tonight!
Ya'll are already more useful than this company is.. :P
I just hope we don't end up having to buy totally different components.. Ouch..... I don't even own a credit card...

meghammock · January 2011

Re: Battery bank not holding charge--Please help!!

To Cariboocoot:
What does MPPT and PWM stand for, and would it say on the controller what kind it is? I'm going to take a look at that tonight--They sure did sing praises about the controller they chose for us so for their sakes, I hope it's the kind you're saying is better!
I had many doubts about the quality of wiring.. He looked pretty hasty and mechanical (not in the complimentary way:) ) when he was doing it.. Any way I can check myself to see if the wiring is done well and correctly? I did buy a volt meter the other day.. I have no clue how to use it but I would really like to know how to check all of these things!

"I'd be a bit leery of any "expert" who thinks you could connect those batteries in parallel/serial and get 12 Volt at 200 Amp hours. Either the battery rating is wrong or they're talking about usable Amp hours or they can't do math." --Not only did this make me laugh, but it gets close to confirming a suspicion of mine.. I'm not sure where they got some of their figures from! They said they were giving us a 700+ watt system for beginners, and as your (correct) math shows, 173 x 4 isn't exactly 700+ :P

Wow, my head's a mess.. Ya'll aren't confusing me, but how they say their system should be working with all of the possible gliches really is......
I'm printing this stuff out and reading more tonight........

BB. · January 2011

Re: Battery bank not holding charge--Please help!!

You might also take a look a this RV blog. From our Host (Windsun):

For 12 Volt & RV Systems - HandyBob's long discussion and rant is about 99% right on how to make RV and similar 12 volt systems work correctly. One of the few "non NAWS" articles that we recommend.

Usually the problems end up:

Using more power than the panels can recharge (assuming more power from panels than they can deliver, using more loads, standby losses from inverters, etc.).
Not using deep cycle batteries (Marine/other types)
Improper Wiring
Improper configuration of wiring
Less than optimal configuration of charge controllers
Not using a genset (properly) to recharge the battery bank on low sun/heavy load days.

It sounds like you have close to a 200 AH @ 12 volt battery bank.

A 3kW inverter is pretty big for an RV system as the primary inverter. A large inverter like this may use 30-60 watts just turned on with no loads.

If you are charging the battery bank (no other loads), it should reach around 14.5 volts and be held there for several hours to get the bank recharged...

At this point, it may take 2-3 days to fully recharge a "dead" battery bank with no loads with that size of array. Assuming the batteries are still good (batteries do not do well if taken to dead--or less than 11 volts or so--it can permanently damage one or more battery cells).

I have also seen paralleled batteries that have a poor "cross over" connection between the paralleled batteries--and only 1 battery is charging / discharging--the other bank is effectively disconnected.

-Bill

meghammock · January 2011

Re: Battery bank not holding charge--Please help!!

To BB:
I will definitely check that RV link out when I'm back at my computer tomorrow! Thank you!

"I have also seen paralleled batteries that have a poor "cross over" connection between the paralleled batteries--and only 1 battery is charging / discharging--the other bank is effectively disconnected."----I've been curious about this.. We can fully charge the battery bank via generator/charger, but it still depletes VERY quickly.. This has been so since the start and they claim they've checked the connections, but I was there when he was putting it together and I thought (with my limited knowledge, I admit) he looked pretty sloppy when he was doing that part.. Is it safe for me to fiddle with those wires and check it out? Any tips on what exactly to check for?
I did mention to them that I thought a 3k watt inverter was a bit excessive and power-eaty but they said "Oh, no, it only pulls 0.1-something amps--it's not taking much".. That's cool on the amps I guess, but what the hay does that mean with watts?! :P
So do you mean that once we do charge the batteries, we should let them set, inverter off, for a couple of days to help them hold the charge better?? Or did I just confuse myself?

They didn't explain any of the recharging stuff to us.. It's like pulling teeth from a dinosaur to get any answers.. We'd be further up the creek if I didn't have ANY previous knowledge! Not saying what I do know is much, but.... hehe:)

Cariboocoot · January 2011

Re: Battery bank not holding charge--Please help!!

Trying to be helpful here and not confusing :roll:
Glossary of terms: http://forum.solar-electric.com/showthread.php?t=6136

The PWM controller is basically a "switch" in that it connects/disconnects the panels from the battery according to preset Voltage levels. The MPPT - Maximum Power Point Tracking - can "down-convert" higher Voltage panels giving more usable charge Amperage for a given system Voltage. Your panels are of the "more than 12 Volt, less than 24" variety (referring to nominal Voltages) and so would work most efficiently on a 12 Volt system with the MPPT controller. They don't put out enough for a 24 Volt system, and with the PWM controller much of the power will simply be lost as the Voltage will be "dragged down" to ~14.2 and the panels will not run at their best level (Vmp - Voltage at Maximum power).

If the batteries have been repeatedly discharged and improperly recharged they will have lost capacity. This is the "not running the lights for even 2 hours" kind of effect. They may read 12.75 Volts "resting", but instead of having 215 Amp hour capacity (for example) they'll be down to perhaps 175 or some such lower number.

If these batteries have "caps" (not sealed) you can get a hydrometer from an auto supply store and check the Specific Gravity of each cell yourself, after charging and allowing the batteries to rest. You can tell quite a bit about the condition of the battery from the SG readings.

Who sold you that Honda 5kW gen? Seems a bit of over-kill to me. Probably one of the EU2000i units would be more suitable. They're very quiet and very fuel efficient.

icarus · January 2011

Re: Battery bank not holding charge--Please help!!

Before you get too frustrated, do a real load calculation. Many people have no real idea of how much power they actually consume over the course of a day.

It is a pretty simple equation when you get right down to it. Use 100 watt/hours of power, you have to generate 120 wh to recharge.

The rule of thumb that I use for battery based systems is as follows: Take the name plate rating of the PV, divide that number in two to account for all cumulative system losses and charging efficiencies, then multiply that by 4 to represent the average number of hours of good sun one can reasonably expect each day over the average year.

So in your case, 173 watts of PV might look like this: 173/2=86.5*4=346 watt hours per day, average. Now you might do better, you might do worse, but on average you are probably going to be pretty close.

So, if you are using more than ~ 346 wh per day, you are likely fairly quickly killing your batteries.

The hard reality is that most people over estimate the amount of power they can harvest in a given day, while at the same time underestimate the amount of loads they are taking out.

Your 375 wh would run a 100 watt TV for 3.75 hours, or the same TV for 1 hour, and 4 15 watt CFL bulbs for ~ 4.5 hours, or some combination thereof.

Just for comparison, we live 100% off grid. We have 400 watts of PV, into 450 amp hours of battery, and we routinely use ~ 5-700 watt/hours/day. I would doubt if you are using much less in an RV.

One final note, RV inverters (especially those that claim 3000 watts running with 6000 watts surge) are notoriously inefficient. I have seen some that have huge stand by draw even when not powering anything.

Good luck, and keep in touch,

Tony

Please also note, that RV installations are not usually optimized for greatest harvest, since they sit flat. Also any shading what so ever will cut your harvest to near zero, even a wire casting a shadow on the Panel. Hot panels will put out less, and most people don't like parking RVs in the sun!

BB. · January 2011

Re: Battery bank not holding charge--Please help!!

I believe this is your inverter:
www.durafied.com/?page_id=13&shopp_pid=2

Model Number:S3000DIIncluded:POWER INVERTOR POWER CABLES (2 Sets of cables for model) ($30.00 VALUE)Specs:Max continuous output – 3000W Peak/surge capacity – 6000w Normal Input voltage – 12V, DC Input voltage range 11-14DC Max efficiency – 90% Output voltage – 115VAC ± 5% Output frequency – 60Hz ± 2Hz Output waveform – Modified Sine Wave Low voltage shutdown – 10.5 ± 0.5V Over voltage shutdown – 15.5 ± 0.5V No load current draw – 0.7A Recommended input wire size – #2 Recommended ANL fuse size – 500A Dimensions – 14-1/4″ Length x 6″ Width x 6-1/4″ Height Built in remote control jack. (Remote sold separately)

They say it draws 0.7 amps with no load--Or:

Power=Volts*Current= 12 volts * 0.7amps = 8.4 watts

That is actually a very low draw for such a large inverter... Hopefully it is true.

Do you leave the inverter "ON" or do you turn it off when you don't need it? (if inverter can turn off).

If you have 4 solar panels x 173 watts near Lynchburg Virgina, your "hours of sun" per day look something like this:

1, 2.36
2, 3.30
3, 4.52
4, 5.39
5, 6.00
6, 6.52
7, 6.38
8, 5.59
9, 4.68
10, 3.64
11, 2.62
12, 2.08
"Year", 4.43

So, January you are averaging around 2.36 hours of sun per day--so power from your solar panels would be around:

4x173 watts * 2.36 hours of sun * 0.52 system efficiency = 849 Watt*Hours per day
4x173 watts * 1/14.5 volts * 2.36 hours of sun * 0.52 system efficiency = 59 Amp*Hours per day at 12 volts

I am not sure how to go from here... There is some math here (Electricity 101) that is not too difficult--but would help you understand your system more.

There is looking at the hardware (exactly what charge controller, how are the batteries connected, etc.).

There is looking at the loads (how many amps/watts times hours per day of usage).

And there is conservation--Understanding your loads and reducing their use to the minimum per day (hopefully matching your solar power availability).

And unless you are using a whole bunch of power (microwave, electric washer, electric coffee makers, entertainment center, electric fridge, etc.)--the 5,000 watt genset sounds to be totally inappropriate (way too large).

One possibility is to add a Battery Monitor to your system (Victron also makes a nice unit). However, you probably would need somebody to install it, then learn how to read it and what it is telling your.

A battery monitor is like a Gas Gauge for your Fuel Tank... You can read the meter at anytime and know how full the tank is (0-100% or 0-200 Amp*Hours) and how fast it is filling or draining (+/- XX Amps).

At this point, I would tell you not to work on the battery wiring yourself if you have never done this before.

Batteries have a huge amount of available current--and in some ways, are more dangerous than working on your 120 VAC wall outlet. Batteries may not shock you with voltage--but they have 100x or more current than is available from your 120 VAC outlet--so the chance of fire, welding your wedding ring or metal wrist watch to the battery (and burning your finger/arm) or causing a battery explosion (hydrogen gas is generated in the cells when charging)--Is just something that I cannot tell you to do over the Internet.

This is a complex task to tackle all at once. Without a "handle" on your loads--It is very difficult to figure out where to begin. We don't know if the system is working well--and you are just demanding too much from it, or it the system is under performing (or both).

My suggestion, get a Battery Monitor, have it installed by a reputable shop (you may want to look at a marina/boat shop too if you don't trust your RV dealer). Any good electrical shop should be able to at least figure out the batteries (if connected well or not) and install the Amp*Hour Meter (Battery Monitor).

Once we get some load/charging information, we can proceed from there.

-Bill

meghammock · January 2011

Re: Battery bank not holding charge--Please help!!

I want to read these most recent replies and chew on the info in those in a little while, but in the mean time, I am curious about this:
On several occasions, we charged the battery bank (with the charger, not the panels) then had NOTHING turned on, plugged in, or anything. Still, the batteries were useless by the time the moon said "hello". We tried it with the inverter ON, inverter OFF, nothing running.. Still nada. All wires and everything were checked and they said they were fine.
What you said, Cariboocoot, is my biggest suspect:
"If the batteries have been repeatedly discharged and improperly recharged they will have lost capacity. This is the "not running the lights for even 2 hours" kind of effect. They may read 12.75 Volts "resting", but instead of having 215 Amp hour capacity (for example) they'll be down to perhaps 175 or some such lower number."
They say they did load tests and individual cell tests, and my thought--correct me if I'm wrong--is, OF COURSE it's going to look good right after you charge it!! Let them set for a little while though, and they'd go right down unless there's sunlight out! (even then, they've been 'kaput' for the past 2 days WITHOUT the inverter on, good sun shining, all 4 panels getting direct light). They DO NOT want to replace the batteries, which I feel they should do anyways since they've run down so many times due to their error--and they didn't hold charge to begin with...
Thoughts??

No worries.. Ya'll are VERY clear and easy to understand.. The info the company was trying to feed just doesn't seen to jive at all! Funny thing is, they have our camper on their website as a functioning, off-grid system.. We didn't even give them permission to post pictures of our setup online yet because their system isn't working.. And yesterday when the hubby confronted them about reimbursing the gas money we've spent running the generator instead of being able to use the system, they stated that we "couldn't afford an off-grid system" (which is what we paid for and they said would work in the first place), and that they want to write up a "buy-back" agreement because they can't please us (you could if you'd make it work, buckaroo!!).. Basically trying to make it our fault that the system isn't giving us power at night! Oh my.. They haven't had answers all along--I've had to re-ask my questions several times in hopes of getting a relevant answer, and still, no answer:( Err.. Sorry for the rant.. I'm slightly upset.. :P

meghammock · January 2011

Re: Battery bank not holding charge--Please help!!

I got the info from the controller last night--Also got pictures to show configurations, but of course, forgot my connection cable for camera. D'oh!

Before I get in to that, Icarus, we did have the company out to test out how much power we were using versus what the system brings in.. We only use the propane furnace and around one teeny light at a time, to give you a general idea of what's being used.. The company was shocked at how little we use and how badly the system performs considering, but still can't find an answer

I don't know the wattage used, but it was only a couple of amps with those on. We even went so far as to turn EVERYTHING on--ALL lights, furnace, microwave, fridge.. And they said our system should still be able to handle all of that (not that I would use the microwave or fridge though..) but for whatever reason, won't.
Like I mentioned in my newest post, we don't even have the camper hooked up to the batteries most of the time and it still drains almost instantaneously!

Here's the info on the controller and whatnot though;
Morningstar, TriStar
TS-60
--Ours DOES NOT have the screen or yellow arrow buttons like the TS-60 I saw on this site. Assuming that means it’s PWM? (about to go look at the glossary of terms). Not seeing how he could alter any settings on the one we’ve got, but not sure… He probably knows something I don’t! :P
12-24-48 VDC

Batteries
Rayovac UltraPro (SLIGC110)
Golf Cart batteries (4, 6v connected parallel and series)
#2 wires connecting batteries
8 gauge connecting controller to batteries

meghammock · January 2011

Re: Battery bank not holding charge--Please help!!

Yes, BB, that is our inverter.. Much better than I thought it would be! Wow!

The company told us we would be getting 4 hours of sun hours per day though.. 2.whatever ain't so great! Ouch!!

Weird though--Seems like the panels charge the camper GREAT during the day! It's just at night when it's the battery banks' turn to strut it's stuff.. ZILCH.

SteveK · January 2011

Re: Battery bank not holding charge--Please help!!

You are getting misinformation somewhere other than here.

They charge the batteries, then load test them, but the batts go dark with no load on them? Within a couple hours?

BBB baby, fry those suckers. Small claims court next....(they probably are unlicensed/uninsured to do all that they do). I have a small business and couldn't fathom treating customers like that... Fry that company of gorrillas and save you neighbors some headaches.

The gang here will get you up and running for sure. Question remains, let these gorrillas continue to monkey around?

Ya' know, you are probably fortunate that the system does not work because if it did you may be an electrocution victim today instead of merely an unhappy customer. I shudder to think of the "proper practices" used in the "professional installation" of your system. Very lucky I'd say......

Website please.......

meghammock · January 2011

Re: Battery bank not holding charge--Please help!!

I think they tested them pre-charge too, and said they were fine.. Does that make a difference??

I'm thinking BBB is a good idea at this point.. So many tests, NO answers!!! Heck nah, we've told them if we don't figure something out, we want a full refund.. They're writing up a buy-back agreement but I don't think they want to refund the money they put in for labor.. Although now that I'm seeing the prices for the inverter and all, I'm curious how much of the cost was actually pocketed.. $6,414 total for the system.. Hmmm......

meghammock · January 2011

Re: Battery bank not holding charge--Please help!!

Here's the company's site, if anyone's interested:
http://www.solarsystemmadeeasy.info/Home.htm

Not much easy.. Misdirecting name and information on Mission page, eh?!

Cariboocoot · January 2011

Re: Battery bank not holding charge--Please help!!

So it looks like this is your charge controller: http://www.solar-electric.com/tr60amp12244.html
That's the wrong one. It should have the MPPT designation in the model: http://www.solar-electric.com/motr60ampmps.html
And anyway you wouldn't need a 60 Amp controller for 4 173 Watt panels. Technically they could hit 48 Amps, but I doubt it would ever really happen.
Without the MPPT function you won't be able to convert all your panels' Voltage into current, assuming the Vmp is 25.1 as it appears to be. Normally the Vmp on a "12 Volt" panel is 17.5 or so. Roughly speaking, you're only getting about 130 Watts per panel instead of 173. If this info is all correct.

According to their site, the Ray-O-Vac SLIGC110 is a 215 Amp hour, standard golf-cart battery. Even with the reduced panel output they should be charging. So it's definitely time to charge the batteries up independently, let them rest, and check the SG. Then look at the wiring. It ought to be 2 AWG connecting the batteries & inverter. And they should be wired "diagonally" as per "method 2" at Smartgauge: http://www.smartgauge.co.uk/batt_con.html

meghammock · January 2011

Re: Battery bank not holding charge--Please help!!

Is my controller an older model then? Because it doesn't have that little screen at the bottom or the yellow buttons.. I don't think it says on the actual inverter whether it's the MPPT or the other, does it?
Their explanation for having the controller and inverter so big was so that we could expand the system more easily when we were ready to, but seems like that's done more harm than good..

Hehe.. Guessing SG is another term I need to look up?

Could I check that with a volt meter? ..and how long does a bank typically need to charge to be full? They said they did it for 5 hours.. That seemed a bit wild to me...

"Diagonally", eh?? I've never heard of that.. I must take a peek.....

mike95490 · January 2011

Re: Battery bank not holding charge--Please help!!

meghammock wrote: »

Here's the info on the controller and whatnot though;
Morningstar, TriStar TS-60

Batteries
Rayovac UltraPro (SLIGC110)
Golf Cart batteries (4, 6v connected parallel and series)
#2 wires connecting batteries
8 gauge connecting controller to batteries

You are loosing half your solar power [30V ?] in waste with the PWM controller. You should have the
Morningstar, TriStar MPPT-60, with the added meter ($$).

There is a $300 difference between the PWM and the MPPT controller, and another $100 for the meter. If you wire it up to a laptop, you can get about the same info on the laptop, skipping the meter. (the MPPT 45 does not have the web server in it, and would need the meter)

BB. · January 2011

Re: Battery bank not holding charge--Please help!!

Lots of replies--I will try and keep track of those I can answer...

The TS-60 is probably a PWM controller... And it is a perfectly good controller from a company with a good reputation. There are newer models (MPPT) but it is more expensive.

Need to look very closely at the model number--there is a TS-60 and a TS-60 MPPT (how ever that it marked).

The display/buttons are an extra cost option from MorningStar (MorningStar is known for the extra price options:roll:).

Your issue (or your Installers). If they have the "plain" TS-60 -- All PWM controllers need to have matched voltage to battery bank voltage setups for optimum power collection. If you have GE panels with Vmp=25 volts and a PWM controller--that is a significant mismatch which gives you less power. Normally, for a 12 volt battery bank, PWM controller with Vmp=17.6volt panels is used...

It is a bit of a complex issue--Sometimes it is less expensive to use a less than ideal 173 watt 25 volt panel vs a perfect 135 watt 17 volt panel.

A MPPT type charge controller would be better at getting those extra watts--but the MPPT controllers are a few hundred dollars more (against $6k, not a very big difference).

A PWM controller will work fine (less power) and does not sound like it is "the problem" here.

SG is Specific Gravity of your battery bank electrolyte. Basically if your batteries are "Dead" the SG is very near 1.000 (the SG of water). If your batteries are 100% charged it will be around 1.27 (1.27 x as heavy as pure water). 50% charged is around 1.20 s.g.

You can get a hydrometer from the local autoparts store, or get better ones like these.

Regarding the basics--It sounds like you have one of two problems.

Batteries are Toast--They need to be replaced from age or taking to completely dead.
Batteries are OK--But there is a wiring problem. You have a poor connection somewhere that is preventing current flow to the battery bank.
Batteries are Toast and Wiring Problem too--Wiring fault eventually killed battery bank.

If the RV guys are correct, you have issue #2...

It is possible that #3 has or eventually will happen if it is not fixed.

The batteries will take longer than 5 hours to recharge from near dead (would need details on AC battery charger to give you better estimate). But even with a short charge time--The batteries should not be dead a few hours later when the sun goes down.

Regarding the Inverter--That sounds like a low standby power draw--but I would like to confirm that the specifications are real. Just don't know.

There is something being missed. When your system is "dead" -- It should take about 5 minutes with a volt meter to figure out where the problem is.

Either the batteries are "dead" (12.7 volts if charged, 12.1 if 50%, and 11.6 if 20% state of charge). Or the batteries have a charge and there is an "open" or "poor" connection somewhere in the wiring from the battery to your main power panel.

Need to start with the basics. Other things like "diagonal" connections, PWM vs MPPT, large genset, and such, are "second order effects". They will eventually need to be addressed, but they are not causing the major issue as you describe it here. And I would ignore those for the moment. It will help avoid getting distracted from the main problem(s).

If you remove rings/jewelry/watch with metal band/etc. and wear safety glasses (to keep acid out of your eyes if something goes wrong)... A simple digital volt meter, connect one lead to ground and start measuring the 12 volt battery voltages at various points in your DC wiring will be pretty safe and help you identify what is failing.

-Bill

meghammock · January 2011

Re: Battery bank not holding charge--Please help!!

Would that power be taken from the panels themselves as they soak it in, or the battery bank? Assuming the panels, but not sure..

mike95490 · January 2011

Re: Battery bank not holding charge--Please help!!

meghammock wrote: »

Would that power be taken from the panels themselves as they soak it in, or the battery bank? Assuming the panels, but not sure..

The panels only output power when the sun shines on them. What power the batteries don't absorb, is lost forever.

BB. · January 2011

Re: Battery bank not holding charge--Please help!!

I would measure the voltage at night when the batteries are "dead".

It sounds like the solar part is at least working--What you need to figure out is why the batteries are not working well (battery bad or wiring bad).

If you measure the voltage with the sun up (and/or generator running)... It is useful information but would make things a bit more confusing regarding the first question--Batteries Good or Bad. Wiring Good or Bad.

When you have alternate sources of power (solar panels, generator) it becomes more difficult to figure out if the batteries (and their direct wiring) are good or bad.

Sort of "back to basics". We are looking for, pretty much 12.x Volts or much less than 12.x volts.

If we do it with the solar/generator running--We would be talking about 12.7 volts vs 13.6 or 14.2 or 14.5 volts and 11.93 etc... Can be done-but would be terribly confusing and frustrating to try and help you with Internet Posts and teach you at the same time.

-Bill

meghammock · January 2011

Re: Battery bank not holding charge--Please help!!

Would I need to stick the black or the red lead in the ground?? That is good stuff.. Strikes a chord.. Of course, it's raining/sleeting/snowing so I proooobably shouldn't do that today.. Although they want to do they buy-back possibly tomorrow... Hmmmm..... Would I still need to ground the meter if I just check batteries since it'll be dry in their tote??
Dude, LOTS of good info....... Thank you:)

meghammock · January 2011

Re: Battery bank not holding charge--Please help!!

Would I be creepy for allowing phone calls if that'd work better? :P

Hmm.. I will see if I can check that tonight.. Assuming I don't' have to put the meter rod in the ground for battery test? I guess I could put the rods on both terminals (positive and negative) on the batteries and "problem shoot" from there to figure out how to properly evaluate voltage?
I'm tempted to go video the battery bank so you can see exactly what we're looking at..

meghammock · January 2011

Re: Battery bank not holding charge--Please help!!

Seems like whatever power the batteries absorb, is lost forever, too.. hehe :P
Even after a full charge from the battery charger, they poop out almost instantaneously. I'm starting (thanks, guys!) to think it's definitely a battery/wiring issue. Too bad we have to figure it out instead of the company, huh?!

BB. · January 2011

Re: Battery bank not holding charge--Please help!!

"Ground" is slang for the metal frame/return/negative lead on your battery bank.

"Ground", earth ground, or Safety Ground is an issue with AC power in your home/business/NEC 120/240 VAC wiring... But for your DC system--it is just like working with giant (and more dangerous) flash light batteries.

Do you have a Volt meter (or DMM--digital multi-meter)?

Here is a quick and simple Multimeter Tutorial. Review it first then we can talk.

For the meter--if you have it set to VOLTS scale--it is pretty safe to use.

Do not set it for CURRENT or OHM/RESISTANCE scale. Those, when connected across a battery can cause you to use your safety glasses.

Some other training links:

How to Use Digital Multimeter
The Basics of Digital Multimeters
How to use a Multimeter

-Bill

niel · January 2011

Re: Battery bank not holding charge--Please help!!

"I guess I could put the rods on both terminals (positive and negative) on the batteries and "problem shoot" from there to figure out how to properly evaluate voltage?"

don't do that as that is shorting out the battery.

mike95490 · January 2011

Re: Battery bank not holding charge--Please help!!

BB. wrote: »

...

Do not set it for CURRENT or OHM/RESISTANCE scale. Those, when connected across a battery can cause you to use your safety glasses.....

and buy new pants.

http://www.youtube.com/watch%3Fv%3DEwyf9mzIfi0&sa=U&ei=_YNATbPXJsnagQeB0oigAw&ved=0CBYQtwIwAg&usg=AFQjCNF6MwER3ektvt-8KdiMXsZeq_ZKwA

http://forums.mikeholt.com/archive/index.php/t-54060.html?

Battery bank not holding charge--Please help!!

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