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-   -   Batteries dying/not charging converter upgrades etc. (

Michael_TW 08-16-2019 11:48 AM

Batteries dying/not charging converter upgrades etc.
I have an interesting situation (2016 25' flying cloud, 2 6V in series):
Batteries have been dying from using "store" mode, recently upgraded to 4 stage converter (4655VL PD 4655VL 55 Amp Converter Upgrade), checked voltages at battery were good when battery disconnected. Batteries charge fine on separate battery charger but did not charge in "use" mode when plugged in for a month or while camping.

Our Battery voltage sensor in cabin have always been off by at least a volt compared to multi-meter at battery terminals suggesting some sort of bad wiring to have a 10% voltage drop. With batteries connected battery terminals read battery voltages not converter voltages, even though voltage measured at converter in the interior is correct according specification (eg. 14.4V but at battery)

Our use/store switch was acting funny and seemed like it was not engaging/disengaging properly, I am thinking that there is something funky going on with the wiring/switch itself. Not sure where to start, we've been through about 4 sets of batteries. The next thing I will be adding a mechanical battery disconnect in the battery compartment, but if I can't get the batteries to charge on AC then I don't know what the F's going on.

hhendrix 08-16-2019 12:27 PM

Disconnect from shore power and measure the voltage directly at the battery terminals. Reconnect to shore power, put the switch in the use mode, and again measure voltage at the battery terminals. If the charger is working the voltage should be 13.6 to 14 volts. Also check the water level in the battery cells. If the cells were ever low on water for a period of time, the plates can become sulfated and don't take a charge very well. Remember to only use distilled water to fill the cells.

Michael_TW 08-16-2019 01:07 PM

I replaced the 6V batteries a couple months ago, put them in, RV sent RV to service, batteries came back dead 1 month later. Tried charging, took back to store, they charged them fine. Turned out my 12V charger was a piece of crap. Bought a new 6V/12V charger, charged batteries fine. Batteries weren't charging on "Use".

replaced converter, batteries weren't charging on shore power at home or AC generator during first 3 days of camping trip. Charged batteries with separate charger on 6V with batteries out of trailer and during boondocking in 12V mode by switching to "Store". back from camping, and still on shore power batteries are not charging even after couple of weeks.

with shore power on, batteries disconnected, voltage at battery compartment terminals from converter is 14.4, 13.6 whichever mode is selected. once batteries connected voltage reads only battery voltage (possibly expected as voltage drop due to current etc.) however batteries don't charge even after a month.

during camping lights would flicker, determined that the use/store terminal wasn't fully engaging all the time

since we bought the trailer, the battery monitor (see-level) voltage is always off by at least 1 volt or so compared to multi-meter across batteries.

looking for ideas! thanks

PKI 08-16-2019 03:01 PM

So, something is killing your battery charge. And something is stopping the converter from charging.

Step 1 - find the load that kills battery charge. Disconnect batteries with a disconnect switch when storing or disconnect cables when storing.

Step 2 - verify why your converter is not charging your battery.
a......your solenoid may not be functional, or it may be intermittent
.....i.....during camping lights would flicker, determined that the use/store terminal wasn't fully engaging all the time
(may be your problem) may not be correctly using the store/use switch positions positions
c......your battery may not be correctly installed
.....i......verify that all cables are connected and connected corectly
.....ii.....verify that the always-on bus fusing has not failed
.....iii....verify that the battery cables to the inverter are still correctly installed
d......verify you're ground system is correctly connected to frame & ground bus
e......verify all fuses are installed and functional

Step 3 - verify your battery is correctly maintained
a......your battery is charged to capacity and never discharged below 12.2volts-50%
b......your batteries have water
c......your battery connections are clean

Step 4 - get an expert to run down number 2 if the above is not logical to you

Spend some time with your coach electrical schematic. Understand that the inverter circuit needs to be understood as well.

Understand that a battery does not read correctly if it has been connected to a load or a charger/converter in the last 30-60 minutes.

Understand that the difference between the volt readout on your panel and the direct reading with a multimeter on your battery is likely a load on the system and surface charge on the battery bank. Equalize by disconnecting loads - all lights, the refrigerator, the subwoofer, the lug monitor any inverter load (turn it off) and similar parasitic loads on the trailer. Also turn off the charge to the battery by properly using USE/Store switch. The other way is to disconnect shore power. What you get on the panel is then battery voltage only.

Sounds complicated, but it's just one step after another. You will learn as you progress through the system. Hope these ideas help you investigate your problem. Pat

CBWELL 08-16-2019 04:10 PM

Do a load test on your batteries. If you don't have a tester, take them to a battery store such as Interstate, and they will test them for you. Very often the problem lies in your batteries, especially if they have been fully discharged.

jnm30327 08-17-2019 03:37 PM

I have had trouble with the 110V breaker that feeds the converter dropping out. Worth checking if you think the converter is not running. If it needs a reset, push it down to reset and then push up to restore power. This is a longshot, I know; equivalent to "is it plugged in".

NoResults 08-17-2019 08:50 PM

Another thing to check is a small wire on the side of the solenoid that your use/store switch activates.

On my previous trailer this wire was only finger tight and showing some of these same issues.

Good luck.


Michael_TW 08-19-2019 03:34 PM

Thanks for the ideas, will check in next month or two and post my results. Much appreciated.

GOUSC 08-19-2019 03:48 PM

Is it possible that it's something as simple as the fuse to your converter tripped to the "off" position. This happened to me in the past. Fuse off = no charging when connected to shore power.

If you have solar panels they should charge the batteries regardless of the converter being on or off.

PriscillaQoD 08-21-2019 01:53 PM

I had same problem. Turns out the propane detector is always on even when in "store" mode. always depletes batteries. Unless you have solar. I ran through two sets of batteries before I had a cutoff switch installed so when the store button is pushed the propane detector is off.

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