Batter charging?

Ol 54'

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How many volts would be required to charge up my battery in my 5th wheel? There is an inverter which runs off 120 a.c volts. I am thinking my inverter might be toast, hopefully not. In the battery comp
Where the battery is located, would I check the voltage on the D.C. scale or the A.C. scale with a multimeter?
 
The battery in the RV would be 12 volts DC. Just use a regular car charger to charge it up. The circuits on the other side of the inverter at the breaker panel would be 120 volts AC. Next to the AC breaker panel you might have a DC panel with regular fuses like you have in a car and those would be 12 volt DC.
 
How many volts would be required to charge up my battery in my 5th wheel? There is an inverter which runs off 120 a.c volts. I am thinking my inverter might be toast, hopefully not. In the battery comp
Where the battery is located, would I check the voltage on the D.C. scale or the A.C. scale with a multimeter?
A fully charged 12v battery should read 12.6 volts using the dc position on the meter and at least 20 volt range, after sitting off the charger for 15 minutes, and not connected to anything. Jim
 
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It's called a 'power converter', not an inverter. (An RV inverter converts 12V DC to 120V AC. Your RV may also have an inverter, or it may have a device that does both. But right now we're only concerned with getting your battery charged.) First check your battery without plugging the RV into AC. It should be around 12 to 13 volts DC. If it's much below 11 volts, it's probably toast, but try to charge it anyway. When you plug in the RV to AC power, the voltage at the battery should start to rise and eventually get above 13 volts. If the voltage doesn't rise, there's probably a problem with the power converter.

One thing to check is the two big fuses in the panel of the power converter. They're usually around 50 amps, and exist to protect the power converter from installing the battery backwards. It's pretty easy to blow them if you're not careful.

RV power converters intended for lead-acid batteries have three or more 'stages'. When the RV is first plugged in and the battery is low, the converter goes into 'boost' or 'bulk' mode and charges at around 14.4 volts. When the battery is almost fully charged, the converter switches to 'normal' or 'absorption' mode which is about 13.6 volts. After a few hours, the converter switches to 'storage' or 'float' mode at around 13.2V. The better converters also have a desulfation mode that occasionally kicks in while in storage mode.

If you have the WFCO power converter that's standard in most smaller RVs, consider upgrading it with a Progressive Dynamics power converter. PD makes a unit that's a slide-in replacement for the guts of the WFCO converter. The PD power converter is four-stage versus the WFCO's three-stage.
 
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The battery(s) in your 5th wheel is(are) a normal everyday 12V lead acid battery, same as the one under the hood of the truck you pull it with. They call them "marine" batteries but the differences from a normal vehicle battery are minimal. Treat it the same as your truck battery.

Find the battery box on your 5th wheel, open it up, and attach your regular old battery charger same as you would on your truck or tractor.

An INverter turns 12V battery voltage into 120AC so you can use appliances without being plugged in. A CONverter plugs into 120AC power and provides 12V DC power to run all the 12V stuff in your 5th wheel, and charge the battery. IF you go to the RV dealer and ask for an INverter, you will get the wrong thing, and they probably won't be smart enough (or won't care) to ask the right questions. You are dealing with a CONverter problem.
 
FWIW, every time we take our RV on a trip I check to make sure my truck is charging the RV battery. The truck has a fuse for the trailer battery charging circuit that can blow if the battery is seriously discharged. Just check the battery voltage with the truck hooked up and the engine off. Then start up the tow vehicle and check the battery again. The voltage should rise slightly, maybe a tenth of a volt. If there doesn't seem to be any change, check the truck's 'trailer battery' fuse.
 
Good Mornin 54, good questions:

1) How many volts would be required to charge up my battery in my 5th wheel?

2) There is an inverter which runs off 120 AC volts. I am thinking my inverter might be toast, hopefully not. In the battery comp

3) Where the battery is located, would I check the voltage on the D.C. scale or the A.C. scale with a multimeter?

I will start with my short answers and expand below:

1) Your RV House Battery, if alls well, would be 12.6 volts iffffffffffffffffff fully charged ? (less if discharged). In order to charge it a voltage of at least 13 up to around 14 + is required. That can be supplied by a powered up working Converter/Charger when plugged to shore power....

2) I doubt you have an Inverter, they take 12 DC battery volts and Invert it to 120 VAC. You more likely have a Converter/Charger which takes 120 VAC and Converts it to 13/14 VDC to charge your RV house battery and power 12 volt RV appliances. When plugged to shore power thats when a working powered up Converter/Charger charges your house battery.......

3) To operate the Converter/Charger requires 120 VAC on its INPUT (via a 15/20 Amp circuit breaker in RV electrical panel) and will have 13/14 Volts DC on its OUTPUT (connects to your RV battery) to charge your battery. There may be a breaker or overload or fuse on DC output side (or wires to battery) of your Converter/Charger CHECK THAT !!!

FOR YOUR INFORMATION

1) If the RV is plugged to good 120 VAC shore power, and iffffffffffffffff your Converter/Charger has 120 VAC input power and is working and its DC output side is connected to your RV house battery, iffffffffffffff there are no blown fuses or circuit breakers on input or output side (insure theres no blown fuses or tripped breakers or overloads and a good connection from Converter/Charger output to battery) THATS WHEN YOU SHOULD SEE 13 TO 14 VOLTS DC ON THE BATTERY. There may be a fuse or circuit breaker on or from the charger to your battery CHECK THAT !!!!!! your battery wont get charged if there's no connection or a blown fuse etc from charger to battery!!!!!

3) If plugged to shore power you would first insure there's 120 VAC to the Chargers INPUT (check 120 volt panel circuit breakers) with an AC Voltmeter (or see if power on lights are indicating etc) and use a DC Volt Meter to check battery voltage which should be the voltage on Chargers DC output.

MORE FYI

Older RV's Converter/Chargers were more like constant voltage around 13.6 VDC while later Converter/Chargers are so called SMART CHARGERS that may use 3 stage charging with staged Bulk Charging (around 14 VDC),,,,,,,,,,,,,AbsorptionCharging (around high 13),,,,,,,,and Float Charging (around low 13).

Many Travel Trailer house batteries may use the tow vehicles alternator to supply some small degree of charging to the house battery via the 7 pin round RV plug. HOWEVER thats only a limited amount of charge current and if alls well if you check your RV house battery voltage before then after starting the tow vehicle, the RV house battery voltage may rise slightly.

PLUG UP THE RV TO SHORE POWER,,,,,,,,,,,,,,,,INSURE THERES POWER TO THE CONVERTER/CHARGER (120 VAC breakers ok, power and lights on Charger),,,,,,,,,,,,,,,CHECK ANY FUSES OR SWITCHES OR BREAKERS OR OVERLOADS ON CHARGERS DC OUTPUT TO BATTERY,,,,,,,,,,,,TEST BATTERY VOLTAGE (should rise to at least 13 up to 14 or so) PS CHECK CIRCUIT BREAKERS IN YOUR RV ELECTRICAL PANEL !!!!!!!!!!!!!

NOTE insure battery has electrolyte level above all the plates,,,,,,,,,,,, Have them checked and load tested at an auto store,,,,,,,,,
A TOTAL SHOT BAD BATTERY (or if there's no good connection charger to battery) MAY NOT TAKE CHARGE EVEN IF ALL ELSE IS FINE

I hope this helps, post back any questions.

PS I can't know from here if your RV battery is a regular wet Flooded Lead Acid (FLA),,,,,,,,,,,,,,,,,Or an RV Marine Semi Deep Cycle FLA,,,,,,Or a Full Deep Cycle FLA,,,,,,,,,,,,,,,Or an AGM (Absorbed Glass Mat) ?????????? I seriously doubt you have Lithium. The above still applies as far as lead acid chemistry voltages. If you needed to upgrage ??? Id go with at least Deep Cycle AGM instead of wet FLA and if needed a Smart 3 Stage Converter/Charger.

John T Constant 54 year RV owner who spends half his life living in one Been there done that lol
 
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How many volts would be required to charge up my battery in my 5th wheel? There is an inverter which runs off 120 a.c volts. I am thinking my inverter might be toast, hopefully not. In the battery comp
Where the battery is located, would I check the voltage on the D.C. scale or the A.C. scale with a multimeter?
You inverter may or may not also be a battery charger. AND... many inverters that charge batteries,, are very picky about the battery's condition... as if the battery gets too low, the inverter goes into the safety mode and will NOT try to charge the battery. SO... if you were to have the better type inverter,,, you must... disconnect the battery and charge it up at least to around 11.5 volts or higher, or the inverter will not kick into the charge mode... So disconnect the battery and charge it up... see if it charges up, remove the charger, and see if after an hour it holds up at at least 12.6 volts.. if it does, you should be able to reconnect the battery and provide power to the inverter and it should pick up the charging function again.
 
You inverter may or may not also be a battery charger. AND... many inverters that charge batteries,, are very picky about the battery's condition... as if the battery gets too low, the inverter goes into the safety mode and will NOT try to charge the battery. SO... if you were to have the better type inverter,,, you must... disconnect the battery and charge it up at least to around 11.5 volts or higher, or the inverter will not kick into the charge mode... So disconnect the battery and charge it up... see if it charges up, remove the charger, and see if after an hour it holds up at at least 12.6 volts.. if it does, you should be able to reconnect the battery and provide power to the inverter and it should pick up the charging function again.
Good points and indeed they do make combination inverter/chargers but that’s a more recent product. I have no idea what he has but can only guess it’s a converter/charger ??

John T
 
Good points and indeed they do make combination inverter/chargers but that’s a more recent product. I have no idea what he has but can only guess it’s a converter/charger ??

John T
I have the "heart freedom" inverter/chargers, ('90s era) later becoming xantrex .. And they were very picky about the battery condition. Every couple of years you would have to ""reset" them by disconnecting the battery packs and then reconnect them to freshly charged batteries and then they were suddenly happy again... And would go back to the 3 stage charging.. I keep them around for using on the ranch and service vehicles. Still have one in the motorhome. Then there are the smaller generic units that seem to just go bad after 5 years and you have to replace them... on some of the smaller rv's that Ive had.
 
I have the "heart freedom" inverter/chargers, ('90s era) later becoming xantrex .. And they were very picky about the battery condition. Every couple of years you would have to ""reset" them by disconnecting the battery packs and then reconnect them to freshly charged batteries and then they were suddenly happy again... And would go back to the 3 stage charging.. I keep them around for using on the ranch and service vehicles. Still have one in the motorhome. Then there are the smaller generic units that seem to just go bad after 5 years and you have to replace them... on some of the smaller rv's that Ive had.
I had BAD luck with my Xantrex units grrrrrrrrrrr but sure others may have had different experience. No idea what brand type or size the OP has ??
or if its a Converter/Charger (my guess) ,,,,,,,,,,,or Inverter,,,,,,,,,,,,or Combination Inverter/Charger ??

John T
 
How many volts would be required to charge up my battery in my 5th wheel? There is an inverter which runs off 120 a.c volts. I am thinking my inverter might be toast, hopefully not. In the battery comp
Where the battery is located, would I check the voltage on the D.C. scale or the A.C. scale with a multimeter?
13.5--14.0 Volts DC
 
Sorry, I have been missing in action since I started this here thread. I want to thank all of you farmers for your replys. I have run into loose connections coming from what I believe are these two 40 Amp breakers, next to the battery. So far so good, I have been monitoring the battery/ inverter problem. Thanks again you guys are so helpful.
 
I had BAD luck with my Xantrex units grrrrrrrrrrr but sure others may have had different experience. No idea what brand type or size the OP has ??
or if its a Converter/Charger (my guess) ,,,,,,,,,,,or Inverter,,,,,,,,,,,,or Combination Inverter/Charger ??

John T
There is no such thing as an INverter/charger.

CONverters, standard equipment on RVs for 30+ years, provide 12V from "shore power" and charge the battery. They are often the "breaker box" for your 120VAC outlets and appliances in the RV such as the air conditioning.

This isn't one of those situations where you can use incorrect terminology and, "Oh, they'll know what I'm talking about." Inverters are a real thing. They're commonly added as optional equipment on RVs. They have NOTHING to do with charging batteries. If you go to the RV dealer and ask for an inverter, they're going to sell you an inverter.
 
There is no such thing as an INverter/charger.

CONverters, standard equipment on RVs for 30+ years, provide 12V from "shore power" and charge the battery. They are often the "breaker box" for your 120VAC outlets and appliances in the RV such as the air conditioning.

This isn't one of those situations where you can use incorrect terminology and, "Oh, they'll know what I'm talking about."
We'll Barnyard, You might want to be sure what you are talking about also. Here is a link to the combo inverter charger that I had in my RV.

 
We'll Barnyard, You might want to be sure what you are talking about also. Here is a link to the combo inverter charger that I had in my RV.

I will stand corrected on that. Relatively new product I was not aware of.

However I will still stand by my statement that RVs come with CONverters as standard equipment. Your average run of the mill RV doesn't have the battery capacity to power an inverter for more than a few minutes. They barely have enough battery to operate the lights and water pump for a weekend trip without shore power.

This inverter/charger deal is something you'd have to add aftermarket, and if you added it you wouldn't be asking the OP's question.

None of this takes away from the importance of knowing what you have and using the correct terminology, because the two devices do very different things. I've been a member of an RV message board for close to 20 years, and it's a common point of confusion.
 
There is no such thing as an INverter/charger.

CONverters, standard equipment on RVs for 30+ years, provide 12V from "shore power" and charge the battery. They are often the "breaker box" for your 120VAC outlets and appliances in the RV such as the air conditioning.

This isn't one of those situations where you can use incorrect terminology and, "Oh, they'll know what I'm talking about." Inverters are a real thing. They're commonly added as optional equipment on RVs. They have NOTHING to do with charging batteries. If you go to the RV dealer and ask for an inverter, they're going to sell you an inverter.
Actually Victron has made Combination Inverter Chargers a long time and is one of the leading companies out there among those who manufacture and sell combination inverter chargers. I’ve owned RV’s continuous over 50 years and enjoyed the new technology.
I’m actually living in one as we speak and several gents I know are using combination inverter chargers and love them yayyyy lol


Hope this helps best wishes nice chatting with you, check out Victron and several others who indeed make combination inverter chargers

John T
 
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We'll Barnyard, You might want to be sure what you are talking about also. Here is a link to the combo inverter charger that I had in my RV.

You are exactly correct. Inverter Chargers have been around a while and several companies make them while Victron is a leader in the field. In 50 years of rv ownership I’ve seen technology grow.

Yes Virginia there is an inverter charger actually lots of them lol and been around a while

Best wishes

John T
 
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I will stand corrected on that. Relatively new product I was not aware of.

However I will still stand by my statement that RVs come with CONverters as standard equipment. Your average run of the mill RV doesn't have the battery capacity to power an inverter for more than a few minutes. They barely have enough battery to operate the lights and water pump for a weekend trip without shore power.

This inverter/charger deal is something you'd have to add aftermarket, and if you added it you wouldn't be asking the OP's question.

None of this takes away from the importance of knowing what you have and using the correct terminology, because the two devices do very different things. I've been a member of an RV message board for close to 20 years, and it's a common point of confusion.
No problem we all make mistakes now n then I’ve made a ton of them lol

Best wishes take care now

John T
 
Sorry, I have been missing in action since I started this here thread. I want to thank all of you farmers for your replys. I have run into loose connections coming from what I believe are these two 40 Amp breakers, next to the battery. So far so good, I have been monitoring the battery/ inverter problem. Thanks again you guys are so helpful.
Thanks for the update !!!! Put a voltmeter on the rv battery when it’s been setting not plugged to shore power. Plug to shore power and insure the charger is powered up with no blown fuses or tripped breakers or bad connections. See if battery voltage rises to at least 13 up to around 14 ??????? If so it’s working. The battery needs to be okay also or may not accept charge !!!
Best wishes

John T
 
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