Electrical Problem

[Chris362]

Seems as though as soon as I fix one thing, another problem raises it's ugly head.
You've all been so good at helping find solutions in the past, so I thought I'd ask one more time.

2003 National Dolphin
Whenever I am on shore power or generator, everything works fine. The main panel shows the batteries completely charged.
But, when I try to run off batteries alone, the lights go dim within a few seconds, then off and nothing works except for all the lights on the main panel to the inverter/charger that start blinking like the console of the Starship Enterprise.
The generator won't start from the cabin, but will start if I hold the start switch on the generator.

I plug it into shore or start the generator and it all works again.

Tomorrow, I'll have time to take a look at it and I'm looking for suggestions.

I don't think it's a fuse or bad connection because wouldn't that mean no power at all, not a dimming, then off? I'm thinking it's the inverter/charger or a bad battery. Is there an easy way to tell?
Could it be anything else?
Thanks.

 

[Ned]

Sounds like you need new house batteries.  Have you load tested them?

 

[teddyu]

X2

 

[gwcowgill]

x3 but check your connections and ground also..

 

[Lou Schneider]

X4.  Your battery monitor is showing full charge when you're plugged into shore power because it's reading the voltage from the converter.  If the house batteries can't carry the load on their own they need replacing.

The most common cause of battery failure is lack of water.  Batteries normally use water whenever current is flowing in or out of them - they act like an electrolyzer, splitting the water in their electrolyte into the component hydrogen and oxygen gasses.

You don't have to add much water to a car battery because it's not discharged very heavily - just a short burst of current to start the car.  But draining deep cycle batteries and then recharging them is a much longer process, so it's normal for them to use water.

You might try checking the battery's water levels, and topping them off with distilled water if they're low.  They should be filled until the water touches the bottom of the plastic insert extending into each cell - at that point the surface tension will form a fish eye lense in the water to show the cell is full.  But if the cell is dry - the electrolyte level has dropped below the top of the plates for any length of time they have likely sulfated and the battery is toast.

 

[Chris362]

Yikes. There's like 6 batteries tied together in there.
I'm having a problem pulling out the tray that holds the batteries.
There's two catches in front that I open, but it still won't pull out.
Am I missing something or should I force it?

My wife is the one that always forces things and breaks them. I'd hate for her to see me do it. lol

 

[gwcowgill]

Wow, it sure sounds as though nobody has slid that tray out in awhile.... I would spray some penetrating oil along the rails and let it set for several hours and then see if it comes out. I will bet you have 6 dry batteries which unfortunately may not come back up but I would give it a try. Take a picture of how the cables are ran before you start pulling batteries.

 

[blw2]

personally, i wouldn't waste my time trying to revive the batteries.
If they are dry, i would add just enough water to cover the cells, not more. (distilled, and never add water to dead battery except to cover the cells)
then charge
then top them off
then charge again.  If they don't take a charge, or if they don't hold a charge, my experience tells me to not waste another minute with them....

I have killed many batteries in my boat and in my old popup, from neglect.  Letting them self discharge a few times, etc.....
I just spent almost $700 on batteries for the golf cart my father in law gave us..... most of the old batteries tested ok but there were just a fwew bad cells mixed in....
I have tried to revive batteries so often and have never had success..... YMMV
I have seen batteries killed dead by only one two or three deep discharges (letting them go more or less "dead")

If the assumption that the tray hasn't been moved out in a while is correct.... and assuming that you haven't checked the water in a long time.... I would assume that some or all are dry.  Even if only a little bit of the plates are exposed to air, some little bit of damage is done.

And assuming all of that stuff... I'll also assume that you really don't use your batteries all that much so maybe you don't need to replace all 6.  Maybe one good one, or two.... might fit your needs.  Or maybe even a good marine battery might be good enough for your needs

 

[Chris362]

Okay, got it open. I had to grind off the bolts that held the tray to the frame on one side.
I'll look at that later.
There are 4 Powertron 2200g batteries. 6 volt.
One of them had a cable disconnected from one side. It was just laying there and it looks like it occasionally made contact as part of the post at the bottom of the battery was missing.
This was only the third time I used the RV since buying it from Camping World. I'm starting not to like Camping World.

Anyway, 2 batteries were dry below the top of the cells, the other two still had the cells covered. I'll try the charge procedure blw2 suggested.

If I have to replace them, are there any suggestions on what I should replace them with?
Why 6 volt batteries? Wouldn't 2 12 volts do the same thing?

Oh, btw, how long should I give them to recharge before I give up on them?

 

[gwcowgill]

Oh, btw, how long should I give them to recharge before I give up on them?

That is somewhat a complicated question but I would at least charge them overnight and then test if using your inverter. If you have a charger that automatically adjusts the charge rate I would use it and follow the directions. A lot depends on the capacity of the batteries and the state of charge.

 

[John From Detroit]

Dry below the top of the cells is not good, but it might not be all that bad depending on HOW FAR below... My original Interstates got there a couple times,, JUST below (perhaps a quarter of an inch) and they lasted 9 years total.. 

The loose wire can be a major issue.

Re-fill with DISTILLED water to JUST BELOW the bottom of the filler tube, like 1/8 to 1/4 inch below.  Charge,  Test.

Good luck

Till you learn, check at least 1st of every month (This being about the 1st)

 

[Chris362]

Believe me, they will be tested once a month. Either these or new ones if I have to buy some more.

We rarely boondock. I mainly use the batteries to keep the electrical part of the fridge running while moving as I found out it does also need a little electric even when on gas.
(Not a problem our last trip as we ran the generator for the A/C while moving)

The few times when we boondock, we rely mostly on the generator. If we can't run the generator, then a few lights and again, keeping the fridge running is their main use. I don't think I'd ever use the inverter for the TV or other things.... maybe to make coffee. The wife has to have her morning coffee or it would make all these other problems so trivial.

Anyone think I could get by with just 2 batteries? 

Again, thanks everyone for the great advise so far.

(Hopefully, tomorrow I go out and find everything working fine)

 

[gwcowgill]

Chris, If you always have hook-ups you can get by with one 12v. I live in an area that could get a hurricane so I have 2 1250CCA 6v batteries just in case I need to go a few days without power. If you are only looking to run the fridge and a couple lights 2 12v batteries would be fine.

 

[Chris362]

Chris, If you always have hook-ups you can get by with one 12v. I live in an area that could get a hurricane so I have 2 1250CCA 6v batteries just in case I need to go a few days without power. If you are only looking to run the fridge and a couple lights 2 12v batteries would be fine.

So, I could get by on 2 12v batteries.
But, sounds like I would be much better off with 2 1250CCA 6v batteries?

What can you run for a few days with the 2-6s?

...I did a search for 1250CCA and only came up with 12v batteries?

 

[gwcowgill]

So, I could get by on 2 12v batteries.
But, sounds like I would be much better off with 2 1250CCA 6v batteries?

What can you run for a few days with the 2-6s?

...I did a search for 1250CCA and only came up with 12v batteries?

I believe it may be overkill for your application. The batteries I have are the Lifeline batteries which would allow me to run TV, Microwave and satellite receiver with conservative use. 2 6v golf cart batteries are generally sufficient unless you intend to boondock a lot. The batteries I have would break the bank for a lot of people. Look here http://sepbatteries.com/ and see what you need.

 

[teddyu]

Got 2 Interstate GC2-HX (232 AH) for about $130 each in January.  Good to run my CPAP and Furnace all night when in February up in Connecticut.  JM2?...

 

[Gary RV_Wizard]

Ignore the CCA rating on any house battery - the CCA rating is for engine cranking. You want maximum Amp-Hours (AH) or Reserve Capacity (RC). Those are different ways top measure but reflect the same thing - how long the battery can sustain a moderate load (lights, fridge, etc).

A pair of GC2 6v golf cart batteries will give you about 230 AH @ 12v, and that should be fine for your coach. I had a 2002 Dolphin LX and that's all it had as OEM batteries;  it worked fine for a day or two without shore power. Later I added another 115 AH in a third battery and boondocked extensively around Canada and Alaska, with no problems at all.

 

[blw2]

My little coach only came with one marine type deep cycle.... not even a real deep cycle battery.  I don't know the Ah rating off the top of my head, but I'm sure it's not much.
I would suggest that if all you need is a starting battery for your generator, and you generally go from hook-up to hook-up, with maybe an occasional need for a few minutes of lights, or a little bit of use of the water pump, pushing out slides, etc..... then what I have might be good enough.  You could save some money over bying true deep cycle golf cart batteries.
These batteries have a relatively short life even when cared for, so I would suggest not buying more than you need.

Regardless, I hope all of this is a moot point and that you can have success in reviving your current bank of batteries, at least good enough for your needs!

 

[Chris362]

It's pouring down rain this morning, so I guess the batteries will get more charging time before I test them.

I found one of those little battery testers with the 4 colored balls in it. Are those really any good for testing batteries. Not sure how to read it either. I can't find anything on line as to how to use one.
And, can I test them while they are linked together in series or should I disconnect them and test them individually?

Oh, and thanks for all the above comments/suggestions.

 

[Gary RV_Wizard]

You can test the individual cells while the batteries are connected, but the charger should be turned off.

The floating ball type testers usually work by counting the number of balls that float. All 4 should float in a good battery cell, none or only 1-2 indicates a very weak cell. If any single cell in a battery is weak, it effectively drags the other cells down to its level of capability.