The Longest Night

softdown · August 2019

Lost a battery cell in my previously awesome Fullriver bank. Lost another cell in my old 8D bank. Couldn't sleep due to popping a bunch of Sudafed type pills for hay fever - Sudafed is a stimulant when enough is taken. At least I wasn't too groggy when the power went down at ~3:30am.

Had not used the generator for battery charging in so long that I forgot which Outback switch to hit for genset battery charging. Now I feel quite odd with almost no sleep and two battery banks on the fritz. Plus feeling quite weak today after no sleep.

My nose pretty well goes nuts about once every couple years. When it does, no amount of Sudafed will completely stop it. Allergist tested me and said I have no allergies. What I seem to have is very intermittent allergies to something that blossoms between June and August. That isn't the focus of this thread of course.

What are the odds of losing a Fullriver battery cell? I have a replacement battery so not a huge problem. Have lost many cells in the 8D banks I used to use. Used to buy another battery every 2-3 months. Been over two years now.

softdown · August 2019

It has always seemed like a bad cell is akin to a short in the system. Preventing the other batteries from getting a proper charge. Is that logic or fiction?

BB. · August 2019

Depends on how they fail... An open cell (or high resistance) is just that--No or very low charging current in series string and not much discharge current available. The one cell can get hot (if high resistance).

A shorted cell, means lots of charging current in string and the rest of the cells/batteries over charge in the series string. The output voltage of the bank is -2 volts lower, and if there are parallel strings, the shorted string will discharge the rest of the parallel strings over time. All of the cells/batteries in the shorted string can overheat from over charging (again, depends on the resistance of the short).

-Bill

softdown · August 2019

Replacing two batteries can be a chore - depends on your layout. I've lost 20 pounds and almost needed those 20 pounds for moving 170 pound Fullriver batteries.
Right now things seem fine. Though the "bad" Fullriver is thirstily lapping up a charge. So maybe my very tight connection was not tight enough after all. Looked and felt perfect.

softdown · August 2019

BB. said:

Depends on how they fail... An open cell (or high resistance) is just that--No or very low charging current in series string and not much discharge current available. The one cell can get hot (if high resistance).

A shorted cell, means lots of charging current in string and the rest of the cells/batteries over charge in the series string. The output voltage of the bank is -2 volts lower, and if there are parallel strings, the shorted string will discharge the rest of the parallel strings over time. All of the cells/batteries in the shorted string can overheat from over charging (again, depends on the resistance of the short).

-Bill

Is this safety issue something that fuses in front of the strings can alleviate?

BB. · August 2019

Generally, fuses/breakers would not be a big help. Obviously not a help for open cells... And for shorted cells, it depends how "hard" the short is.

Yes, shorted cells are a safety issue. And even an open cell could cause a spark (heavy load takes battery down to zero volts and causes an arch across the open portion of the cell--At least that is my guess).

It does not happen often, but it is possible (bad things happening--more than just "ruining" the rest of the batteries in the string/bank).

One interesting value I read was that if you have a Lead Acid battery bank that is taking >2% rate of charge during float--Replace the bank. It can overheat and catch fire. This is something (lightly shorted cell, simply age causing high self discharge) that you will only see when end absorb current (never drops below 2% to terminate charge) or high float current.

12 Volt banks are very easy to "see" a shorted cell... Bank drops from 12.5 volts nominal to 10.5 volts nominal. Very quick to hit "Low Battery Cutoff" for the inverter.

48 volt banks are where a shorted cell is much less easy to notice... Instead of 50 volts nominal, you will see 48 volts nominal. Still way over the 42 volt typical LBC for a 48 volt inverter and not very easy to "see" on a typical monitor. And why I would suggest some sort of BMS (battery monitor system) for battery banks >48 volts so that a shorted cell is not lost if the noise high voltage battery bank.

Having a series fuse on each battery string--Still not a bad idea. Wrench dropped on battery terminals, battery cable crimp/solder joint fails, cable insulation cut on metal frame/box/etc.--The series fuse per string help prevent other strings from feeding those short circuits.

-Bill

Dave Angelini · August 2019

Sorry ! I thought sudafed was for day use? Can you sleep on it? We used it diving but always used Benadryl at night to sleep.

Take a look at this on your infrared temp probe to maybe see a problem. The high end ones can be a lifesaver on batteries.

softdown · August 2019

Dave Angelini said:

Sorry ! I thought sudafed was for day use? Can you sleep on it? We used it diving but always used Benadryl at night to sleep.

Take a look at this on your infrared temp probe to maybe see a problem. The high end ones can be a lifesaver on batteries.

Sounds like a good plan. Need to get some Benadryl then. No - I can't sleep any with too much Sudafed in spite of taking Melatonin. Nothing worked. I'm one who needs a decent nights sleep. I'll just be a zombie today.

The generator ran for three hours and didn't charge the batteries at all - while the bad batteries were in place. Though it seems like I used to turn off a switch on the Outback inverter for generator battery charging. Thinking it is the bad batteries as the culprit.

Agreed that checking infrared temperature is a sound idea. I had checked the batteries fairly recently but not recently enough. Got a Battery Monitor System on the way.

Dave Angelini · August 2019

The other thing I learned about sleep from the sailboat and weird watch schedules was vitamin D.
If you take it and most of us do need a supplement unless you are in the sun alot.

Take it at night before bed. It promotes the Melatonin and really helped me sleep thru normal nights at sea.
The downside then was we used a cigarette in those days to wake up and stand a watch instead of coffee so we could go back to sleep

On the batteries, can you raise the bulk/abs voltage get the system to go a volt or more above full river spec? Is Outback increasing the setpoint but the voltage is not increasing. You need to burn thru and get voltage up. Use your hands also for feeling heat on the terms.
I should go back and read your findings. Back after the grand jury meeting.....Good Luck

BB. · August 2019

Vitamin D not helpful (bone density, falls, fractures)? "Experts say":

https://ryortho.com/breaking/massive-comprehensive-study-vitamin-d-not-helpful/

Or it is for other stuff:

https://www.healthline.com/health/food-nutrition/benefits-vitamin-d

Or not:

https://www.webmd.com/vitamins/ai/ingredientmono-929/vitamin-d

Just 6 days of casual sunlight exposure without sunscreen can make up for 49 days of no sunlight exposure.

I think "enough sunlight" on skin is more helpful for general health...

-Bill "What would we do without experts..." B.

Dave Angelini · August 2019

All supplements/vitals should be looked at on a blood test in an annual physical. Standard disclaimer! Too much sun is not good either.
Dr. Dave.....

Softdown, are you measuring current? If it is not starting to drop or the voltage is not increasing you will get to point where there probably is not going to be hope. Not there yet but just saying!

softdown · August 2019

Charged a couple other big batteries today - questionable timing on that. Made it back to 47.9 volts last I looked. 2 1/2 days for full charge appears to be a good guess.

Still sicker than a dog. Think it might be a summer cold. Which I can't recall ever having before. Been a lot of stress. A lot. Feeling weak and un-coordinated. Sweat easily. Something is wrong.

Dave Angelini · August 2019

Ouch! Is there a buddy to bug/check on you nearby? Check your temp and BP if you can.
Get rest, good food and 1/2 oz of water per pound of body weight once in the next few days after you sleep.

softdown · August 2019

Had to study up on colds since I get sick so rarely. I have a cold. All of the symptoms. Losing power did not help. Losing a nights sleep did not help.

If the batteries crash in the AM - then I have a big problem on my hands. Not expecting that but disappointed by the charge recovery received today.

The 8Ds were always pretty quick to recharge of course. They were a mistake.

Photowhit · August 2019

Might be a good night just to run the genny and recover.

Tonight might be my 'longest night' in a while. 95 and very little sun. Ran air conditioning most of the evening, It cooled off, but dew point was 76. Kicked back on about 9:30 this morning. Been mostly cloudy, I've only got about 1 days autonomy on the smaller battery from my cabin. 8 years old, I'm sure it's lost some capacity...

I have never had a genny (for my solar electric systems) May reach low voltage cut off for my inverter. We'll see in the morning...

Best of luck!

Update, It's 4:30am and it's cooled off to 71 or so outside and foggy, its a little warmer and muggy inside but air is set at 74 and isn't kicking on and I will deal with just a couple fans... Looks like my system will make it through the night.

Estragon · August 2019

FWIW - I have lots of allergies, most of which have cold-like symptoms. AFAIK, allergists still test for allergies by looking for reactions to common allergens. Although you may not have allergies to the commonly tested-for allergens, you may have a less common allergy.

In any case, whether it's a cold or a less common allergy causing cold-like symptoms, the "cure" is the same. There isn't one. Anytime I've tried to medicate to get relief from symptoms, the side effects have generally been worse than the symptoms.

My father (also had allergies) used to use ephinedrine (sp?) which I think is something like Sudafed. It gave some relief, but also caused cold sweats etc.

Dave Angelini · August 2019

If you have the standard outback distribution panel and the batteries die and are stopping inverting from happening the standard cure is "inverter bypass" this allows you to run on genny no matter what is happening on the inverter side. This may be the switch you were talking about earlier. Buenas Suerte! & Buenas Noche!

softdown · August 2019

Batteries lasted until 6am. Considering that I chose sleep at 7:30pm instead of the usual couple hours of television - did not realize a huge improvement in battery functions. They went out at 3:30am yesterday - but I had watched a couple hours of late evening television.

Right now it appears that new batteries are on the menu. Did not expect that.

Think I will try disconnecting the 8D bank so the entire charge goes to the Full Rivers.

softdown · August 2019

The generator used to speed up when hooked up to charge low batteries. No change in genny speed now. Seems quite odd.

Dave Angelini · August 2019

Glad you are getting better. Are you measuring current? What is it? If the battery voltage is not increasing and the current is staying the same after several attempts, the writing is on the wall.

No change is gen speed says a very low load and is common on a battery that has lost capacity and the other failure types Bill wrote of.

Photowhit · August 2019

softdown said:
Think I will try disconnecting the 8D bank so the entire charge goes to the Full Rivers.

How were these hooked up so that they weren't just one bank of batteries with different resistance for the Full River and 8D?

softdown · August 2019

Photowhit said:

softdown said:
Think I will try disconnecting the 8D bank so the entire charge goes to the Full Rivers.

How were these hooked up so that they weren't just one bank of batteries with different resistance for the Full River and 8D?

Well I still had eight good 8Ds when I grew uncomfortable with the Full Rivers just sitting there for months on end. I left four hooked up figuring they would supplement the Full Rivers and lower the daily discharge level. Watched very closely for quite awhile and things looked very good.

One cable set charges the Full Rivers, another original cable set charges the 8Ds. Some voiced their objections. It would have been difficult to scrap eight good 8D's. Everything was just fine until very recently. Had not checked on things in over a month - way too many new challenges going on.

I was too sick to even check the weather yesterday. Hopefully it was just a cloudy day. That would be nice. Today will be partly cloudy to mostly cloudy.

Having replaced two bad batteries yesterday morning, I certainly thought the batteries would be fine for awhile. Replacing one bad battery had always fixed the 8D battery bank for another couple months. The 8Ds were not that horrible considering that many had been bought in 2011.

Now I wonder if eight GC2 golf cart batteries would do the job. I use about 5 Kw/day.

softdown · August 2019

Dave Angelini said:

Glad you are getting better. Are you measuring current? What is it? If the battery voltage is not increasing and the current is staying the same after several attempts, the writing is on the wall.

No change is gen speed says a very low load and is common on a battery that has lost capacity and the other failure types Bill wrote of.

Will check again in an hour. The genny brought the voltage up from 42.5 to 43.7. Was getting about 5 amps from the solar array roughly an hour ago.

BB. · August 2019

Something is wrong with the charging hardware... You should be getting maximum available amperage from your charging sources (genset/AC charger; solar charging; etc.) until the battery bank is >~56 volts at a minimum (bulk or bulk/absorb transition point; AGM a bit higher, flooded cell higher yet). AGMs at 14.4 volts setpoint (12 volt) or 57.6 volts minimum.

At 42.5 volts (48 volt bank), that is 10.63 volts in "12 volt land"... Pretty much dead.

-Bill

softdown · August 2019

BB. said:

Something is wrong with the charging hardware... You should be getting maximum available amperage from your charging sources (genset/AC charger; solar charging; etc.) until the battery bank is >~56 volts at a minimum (bulk or bulk/absorb transition point; AGM a bit higher, flooded cell higher yet). AGMs at 14.4 volts setpoint (12 volt) or 57.6 volts minimum.

At 42.5 volts (48 volt bank), that is 10.63 volts in "12 volt land"... Pretty much dead.

-Bill

It was very disappointing to only peak out at 47.9 volts yesterday. Then lose power at 6am this morning. Looking at your assessment - is it the panels? The charge controller? The inverter?

It is weird that the genny didn't rev up when hooked up to charge the batteries. It always used to.

softdown · August 2019

Things look more encouraging right now:
Up to 47.2 volts while charging at 14 amp at ~10:30am. At that rate I hope to make 54 volts if the sun co-operates. Which it is not expected to do.

It is highly possible that charging two other batteries significantly kept me down yesterday.

37 degrees latitude if that means anything

BB. · August 2019

Remember that you want to hold ~57.6 volts (AGM) for something like 6 hours for full absorb (and drop below 1% or even below 0.5% rate of charge). Making float 57.6 volts is probably not going to hurt anything for your solar power system... I would worry if float was >2% (enough to cook a battery bank, and really an indication of an end of life battery bank that needs to be replaced soon).

From Marc Kurth regarding Concorde--But would not be bad for AGMs in general:

https://forum.solar-electric.com/discussion/comment/401301#Comment_401301

...

First: I will categorically state that almost every early Concorde battery failure that we see is from undercharging. Undercharging is the enemy and always has been forever. Undercharging can include too low of an Absorb voltage, too short of an Absorb time, too low of a charge rate and not reaching 100% SOC often enough. Way behind undercharging on the list is high temperature. Overcharging is rare to the point of being almost non-existent.

Second: It is MY opinion that Concorde has gradually ratcheted up their support of “conditioning” because customers are so afraid of “over charging” their batteries, that they undercharge them. MOST people do not read (or perhaps ignore) the fact that Concorde batteries must be charged at the Absorb voltage until they are only drawing one half of one percent of the battery bank C/20 rating. Simply put, 0.50 amps per 100 AH of battery capacity.

Dropping to Float before reaching this point is a form of undercharging and will cause sulfation. Their manual also provides suggested Absorb time settings to be used as a starting point to fine tune. Two hours is minimum for very shallow cycling and four hours for deeper cycling. Remember that “end amps” is the key and that lots of Float time brings strings into balance. We often read the internet megaphone about overcharging AGM’s. Think about a typical 1200 ah bank. At 100% SOC, the entire group of 24 batteries is only drawing 6 amps! I assure you that it will take a very long time to cook them. Especially when the sun goes down with great regularity.

There is much, much more to discuss, but I will say that if our battery banks are charged per the manufacturer’s instructions, equalizing is not required for the first 5-7 years. Yes, it is a slightly destructive process, but less so than sulfation!

OK that was wordy! But go ahead tell me what I missed!

-Bill

softdown · August 2019

BB. said:

Something is wrong with the charging hardware... You should be getting maximum available amperage from your charging sources (genset/AC charger; solar charging; etc.) until the battery bank is >~56 volts at a minimum (bulk or bulk/absorb transition point; AGM a bit higher, flooded cell higher yet). AGMs at 14.4 volts setpoint (12 volt) or 57.6 volts minimum.

At 42.5 volts (48 volt bank), that is 10.63 volts in "12 volt land"... Pretty much dead.

-Bill

You seem to have nailed it. Was reading 0.0 charging amps in spite of mostly sunny conditions. Things went bad as temperatures increased. Perhaps there is a short in the solar array cabling leading to the charge controller. Perhaps a bad connection. Ugh - at least as I'm not as sick as yesterday.

Got the genny charging it up now. Seems to be working fine. Will buy me some time to figure out where the fault lies.

softdown · August 2019

Tried turning the CC off and on a few times since it has not been charging the system for awhile. It very briefly says "low light" then goes into "snoozing" mode. And that seem to be the problem right now.

Photowhit · August 2019

softdown said:

... Was reading 0.0 charging amps in spite of mostly sunny conditions. Things went bad as temperatures increased. Perhaps there is a short in the solar array cabling leading to the charge controller. Perhaps a bad connection. Ugh - at least as I'm not as sick as yesterday.

Glad you are feeling better, I likely was one of the people who didn't like 2 different type and ages of batteries hooked up into one bank.

I also see this "16 180 watt Grape Solar with FM80 controller" Did you ever run this through Outback's string sizing tool?

While I haven't, I do understand that the 180 watt Grape panels are 36 cell panels, which we normally call 12 volt nominal panels. With 16 you could only use all of them with strings of 4. Assuming you have been in the heat, the voltage drop may add to any other connection problems and distance they have to travel.

While I haven't downloaded the tool, I have watch much of the video about it and have a screen shot showing they don't recommend strings of 2 - 72 cell panels with a higher vmp than your Grape panels! I know it's a different MPPT CC, but would suggest your FM80 would be better served with higher incoming voltage.

Image: https://us.v-cdn.net/6024911/uploads/editor/t3/nfk7gn1hqzfn.jpg

Hang in there! Glad you are feeling better, even if just a bit.

My system benefitted from a cooler than forecast night. Air barely ran after 9:30-10. I turned it off at some point around midnight.
Overcast all morning. I broke down and took a peek at my system about 11am, Battery was at 27.2 volts in bulk, 4500 watt array producing about 320 watts(yikes!). Guessing 50% maybe 60%. Now I wonder about the batteries current capacity.

I'm luck I'll be in town tonight so the system will get a chance to recover a bit.

softdown · August 2019

It was Outback who warned me (at their web site)about "HyperVOC" than can occur in very cold climates. They said I could only serial two panels. On paper - 3 is fine and I know a guy who does/did installations that way.

I think we are trying to re-invent the wheel with this line of reasoning. It isn't too hot - 74F and the system worked perfectly until a few days ago.

Everything I have looked at looks fine so far. Mostly connections and wiring. Losing a charge controller is not entirely out of the question. I wonder how involved that gets with the Outback MATE system.

The Longest Night

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