Coach batteries are not being charged

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Doc Roads

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Coach batteries are not being charged.  I?m on 50 amp shore power.  Inverter has faulted and shows a low batt warning.  I ran the generator and it did not charge the house batteries.  Batteries continue to discharge overnight and Voltage on coach batteries is now 7 volts. I?ve been reading the manuals but have not found the right answer ... yet. I?m going to start the engine and see if that pushes any voltage toward the coach batteries.  Any ideas will be welcome!

edit by staff - changed message icon to topic solved
 

Gizmo100

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It sounds like your converter is not working.

I would locate the breaker for the converter and turn it off and then go out and unplug the 50 amp plug. (Turn off the breaker before unplugging). Let everything sit for at least 5 min. Then plug back in turn on your breakers and see if the converter come back on line.
 

Doc Roads

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Follow on:  I started the engine and it all goes back to normal.  Coach batteries according to the One Place read out are now at 13.3 volts.  I know the coach batteries were run down.  The LED lights were dim and I had to switch the refrigerator over to AC.  I?m confused by this situation.  One anomaly on the power control system panel ... L1 reads 118 volts and 22 amps ... L2 reads 121 volts and 0-1 amps.  I will look this up too.  Next step is to see what happens when I turn off the engine. I?m letting it run for 20 min and see if theres any change.
 

ChasA

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There is nothing anomalous with 22 amps on one line and zero amps on the other. On 50 amp systems,  you have 2 separate 120 volt lines, each serving different items.
 

Gary RV_Wizard

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When the engine is running you get 12v from the engine alternator fed to the house system. That's why it works and charges the batteries somewhat as well.

Your house 12v system has either a converter/charger or combination inverter/converter/charger that produces 12v from shore or genset 120v power and also charges the house batteries.  What is the brand and model of that unit?    If you have 12v fuses and 120v breakers on the same panel, the name & model on that panel will identify the converter/charger in use.


It's apparent your onboard charger isn't working and there fore the batteries run down.  You said it shows a fault, but did not elaborate on what the fault is. What does the manual for the charger say about that?
 

Doc Roads

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The inverter is a Magnum MS2012.  The fault on the inverter display was Low Batt, and charge reading is 0 (zero) amps.  Manual has information but doesn?t give too much on the trouble shooting side.
 

Doc Roads

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Problem solved.  :))  Thank you Gizmo, Chas and Gary!!!

The manual was of minimal help.  I looked into my basement compartments and finally found the actual inverter/converter.  The circuit breaker on the face of the inverter was popped ... reset the breaker and voila it started to bulk charge.  Of course, I don?t know why the circuit breaker popped.  That reason may raise its head again.  I?m writing a note in my manual near the read out page to check this breaker first.

Again ... Thank you for your response, advice and diligence!

-doc
 

Gizmo100

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:)) :))

Thanks for the follow up.

Strange that it tripped...But now you know where to start if it happens again.
 

Gary RV_Wizard

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All the circuits supplied by the inverter pass through that breaker, whether on shore power or actually inverting.  The MS2012 has 15A breakers (20A on the MS2012B model) on its output circuits, so not difficulty to exceed it's AC output capacity.  Running the microwave or an electric heater plus 1-2 other modest loads is usually enough.  RV manufacturers seldom give much though to balancing branch circuits loads when they lay out the wiring, so its common for high amp loads to gang up on one branch circuit.
The breaker on the inverter usually trips before any branch circuit breaker on the coach load center. Not sure why that is - maybe the inverter makers spec a quick-trip breaker rather than the more common slow-trip breakers used in most load centers.
 

Doc Roads

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Indeed you are the Wizard!  There is in fact a 20 amp breaker on the face of the MS2012 and the situation you described was similar to what happened yesterday morning ... i suspect it was a heating pad ... thank you again!
 
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