Battery not charging - Bad converter? Bypass battery?

[Axebeard]

So I recently moved my trailer a looooong 8 miles up the road to a nicer RV park. First time it's ever been moved in the rain, and we hit a whole host of problems when we hooked up. It's a Surveyor 32BHDS bumper pull.

First off, we smashed our breakaway switch box somehow.

Second, the battery died on us the first night (so no refrigerator, lights, or furnace - and it was like 20 degrees outside).

Third, our fake fireplace electric heater died or shorted.

Fourth, turns out our GFI was tripped (from the rain).

Fifth, we somehow blew the inline fuse that comes off the battery (or into it?)

So here's what I've done so far:

- Took off the breakaway switch box, and connected the wires directly
- Flipped the GFI switch
- Checked all the fuses and replaced the inline fuse from the tongue of the trailer with the fuse from one of the slideouts.
- Dug around under the trailer for a "manual breaker", but didn't find one.

This got us power for about 5 hours. The battery was dead in the morning. I returned the battery and got a fresh one, and also picked up a multimeter. When the battery is connected, I'm reading about 12-13v on it directly. The converter (that's hidden behind my toilet) also seems to be reading 12v WHEN THE BATTERY IS CONNECTED. When it's disconnected, it shows no voltage. I don't know if this means the converter is not outputting enough power or what, because I even switched the AC outlet to make sure it was getting power and it is.

I've also tested the cables that hook to the RV battery with the voltmeter, and they showed NO voltage when disconnected from the battery.

I'd like to find the source of this, because my stupid trailer apparently NEEDS to have a battery to run the interior lights and refrigerator. My fridge is getting NO power without the battery, despite it having an AC mode, so I know my trailer NEEDS a battery to complete the 12v circuit.

If I could bypass the need for a battery, that would be great, but I came up with very little info on how to do that from searching online. I know I need a breakaway switch etc., but we're not planning on moving any time soon so I'll worry about that later.

Having the fuse missing from one of the slideouts wouldn't prevent the whole system from charging would it?

 

[Rene T]

You said you connected the wires which came from the break away box. Don't do that. Disconnect them. What you are doing by doing that is that you're applying electrical power to the electric brakes and draining your battery.  The way the break away box works is that there's a pin on the end of the cable which is inserted in the box. That pin keeps the contacts inside apart. When the pin is pulled, the contacts touch each other causing the brakes to be applied. You have actually done that by connecting the wires. Disconnect them NOW before you burn up the magnets.

 

[Axebeard]

Ok, I'll do that, thanks!

 

[Alfa38User]

.... my stupid trailer apparently NEEDS to have a battery to run the interior lights and refrigerator.

Your "stupid" trailer is not so stupid!!! What you described is how ALL trailers operate. You require a 12V battery for many things including the fridge, water heater, furnace control circuits and the breakaway function despite using 120V for either the fridge or water heater. The furnace is all 12V as are all inside lights (usually).

You probably contributed to killing the battery by bypassing the breakaway circuit as its job is to activate the brakes when a breakaway occurs. By bypassing it, the brakes were on full time even when parked. You will be lucky if you still have brakes as you might have cooked some magnets in them.

Generally speaking, a fully charged battery will read 12.6V, a battery under charge should read about 13.5V or so. The furnace itself is a real battery hog and can easily kill a single battery overnight, depending on the need for heat. You can check the converter output by plugging in the trailer and measuring the voltage across the battery terminals. If it charging it should read at least 13.5V or so. Your converter output may have protection fuses across the output to protect it from connecting the battery backwards. If you read less than 13.5V you may have blown one or both of them.

 

[Gary RV_Wizard]

All the above is correct, but you should not need a battery connected if the trailer is connected to shore power because the onboard converter/charger supplies 12v power in addition to the battery.  However, if the battery is badly depleted, the converter/charger think it is shorted out and shut itself down to prevent a dangerous overcharge situation.  Shorting the wires on the breakaway switch creates a high amp load that both depletes the battery and makes the charger think there may be a short circuit.

 

[Axebeard]

I fixed the breakaway circuit thing by disconnecting the wires, and the battery I'm using has been on a trickle charger while I'm trying to figure this out. Right now the battery is at full charge. I just plugged my converter back in and it gave a little hum and the interior lights came on. (I thought I disconnected the battery?). I went outside to check the battery and only the negative was connected. I hooked up the positive and I'm reading 13v all the sudden. No idea why. Maybe it's because the battery is at 100% instead of the 90% my charger was showing when I was screwing with it yesterday? Either way it appears to be working now. We'll see for how long.

You require a 12V battery for many things including the fridge, water heater, furnace control circuits and the breakaway function despite using 120V for either the fridge or water heater. The furnace is all 12V as are all inside lights (usually).

This is exactly my problem. I don't want or need a battery to be running my vital appliances while I'm hooked up to shore power. Because of this nonsense, my refrigerator isn't working because my battery is not charging. If that's not stupid, I don't know what is.

 

[Alfa38User]

I don't want or need a battery to be running my vital appliances while I'm hooked up to shore power.

It isn't, it is running only the control board and the battery draw for the control boards is very small. You could run the fridge or water heater on propane for a month and not have a battery problem if you start with a well charged battery. Not so with the furnace of course but....

Because of this nonsense, my refrigerator isn't working because my battery is not charging.

Did you not just say your battery was charged?? The fridge should work anyway, despite the battery not charging, as long as it is connected correctly and is not DEAD (12.0V or less). It it turned on?? What lights are lit up?? Make and Model of fridge?? (Please realize it can take up to 18 hours for an RV fridge to fully cool to working temperatures 35-40?, but cooling should easily be noticed in about 3-4 hours or sooner especially in the freezer section.

I hooked up the positive and I'm reading 13v all the sudden. No idea why.

The "Why" is because the charger is working. The charger voltage output (about 13.5V in most cases) has to be slighter higher than a fully charged battery voltage (12.6V) or nothing would charge. Please measure more carefully when reading voltages, not doing so will lead to the wrong conclusions as to what may be going on.

Keep in mind that these RV's are made to be self sufficient and not necessarily be plugged in, that is why the system works the way it does.
If your battery is not charging then you have a problem with the charger, AKA converter or battery wiring, perhaps the fuses mentioned above?

Are you having fun yet??

 

[Axebeard]

Are you having fun yet??

Oh yeah, I've been having fun since the first week we got this thing 3 years ago and the dealer screwed up the wiring on the speakers and said a new speaker would fix it.

We've accepted that every time we move, something WILL break.

 

[Isaac-1]

It is generally a bad idea to run the converter without a battery connected.  Many brands of converters depend on the battery to be present in order to properly regulated DC voltage, without a battery connected various bad things can happen, poorly regulated DC can burn out the control boards on your refrigerator, and your air conditioner, also it can burn out the converter itself.

Ike

p.s. there are a few converters where it is safe to operate them without a battery attached, but unless you know you own one of those better to be safe.

 

[Axebeard]

I had the converter unplugged when the battery was disconnected (for most of the time at least).

 

[Gary RV_Wizard]

p.s. there are a few converters where it is safe to operate them without a battery attached, but unless you know you own one of those better to be safe.

Pretty much any converter/charger since around 1996 will work fine with no battery connected. The "won't work without a battery" concern will soon be an "old wive's tale".

 

[Axebeard]

Pretty much any converter/charger since around 1996 will work fine with no battery connected. The "won't work without a battery" concern will soon be an "old wive's tale".

I wouldn't be surprised if they're using 20 year old converters in these things, because mine sure as hell didn't work without a battery, and it's a 2016 model.

 

[Rene T]

I have a warning label plate right next to my switches for the slides. It says that a battery must be installed to operate the slides. I assume it's because the electric motors draw a lot of juice and just the converter would not be enough.

 

[Gizmo100]

I have a warning label plate right next to my switches for the slides. It says that a battery must be installed to operate the slides. I assume it's because the electric motors draw a lot of juice and just the converter would not be enough.

So the battery can act as buffer to high demands that a converter may not be able to handle??

 

[John From Detroit]

The break-away switch is a cloths pin type device. two contacts and when you insert the plastic pin they grip the pin, but are separated by it.. When you pull the pin. the switch "SNAPS" closed and loccks the brakes.  THIS WILL KILL YOUR BATTERY they suck current big time.

It may also have blown the fuse and done other issuers.


Generally the converter on most modern RV's can power the RV (All but slides and jacks) battery or not but SOME do require a battery. also if it tries to power hte brakes it can blow a fuse or 2 or 3  these fuses are side by side on the converter and must all be replaced at the same time (Remove power before pulling the first fuse so that there is no current when you replace them).

The GFCI. For some reason which I 100% fail to understand some manufactures insist on putting the converter. Fridge and Water heater on GFCI circuits (all or 1 or 2) no reason to do that. but they do it anyway.

 

[grashley]

I will try to summarize what has been said above, and hopefully help you make sense of it all.

The brakes must be off, as many have said.  As Gary said, with the brakes essentially shorting the 12V system, the converter shut itself off as a self preservation move.  As such, it could not charge the battery.  With the converter shut down, the battery voltage measured at the battery and the converter should be the same.  Disconnecting the battery means the voltage at the converter should be -0- because the converter senses the direct short through the brakes, and shut itself off.

With the brake circuit open - disconnected - the converter will again supply power to the camper.  As long as the battery and converter are connected (normal mode), you should get the same voltage reading (or close) at the battery and the converter.  When disconnected, a fully charged battery will read 12.6 volts.  The converter should be putting out at least 13.5V, based on battery charge condition.

The 12V power comes from the battery and / or converter, working together.  It is required for (almost) all lighting in the camper, power for the slides, power for CONTROL CIRCUITS for the A/C, water heater and fridge, regardless of power source used to run the appliance, and power the furnace.

120V is used for any 120V appliances like microwave and coffee pots.  It runs the A/C and can power water heater and refrigerator.  It also feeds the converter.

With the brake disconnect disconnected, it appears the converter IS now working.  The battery MAY have been destroyed by being fully discharged.  The brake disconnect MUST be replaced before you move the camper.  You should be back in business.

 

[Axebeard]

It's been about 16 hours since I fixed the breakaway switch wiring and hooked the converter up to a 100% full battery, and everything seems to be working fine now. The battery is showing 13v and all the appliances are working just fine.

 

[Gizmo100]

It's been about 16 hours since I fixed the breakaway switch wiring and hooked the converter up to a 100% full battery, and everything seems to be working fine now. The battery is showing 13v and all the appliances are working just fine.

) Hopefully things will stay that way

 

[Rene T]

It's been about 16 hours since I fixed the breakaway switch wiring and hooked the converter up to a 100% full battery, and everything seems to be working fine now. The battery is showing 13v and all the appliances are working just fine.

Awesome. Thanks for getting back to us.

 

[BillB3857]

If you had the break-away switch wires shorted for a long period of time, you probably should check the brake magnet in each wheel.  They aren't mad to have full power supplied to them for long periods of time.  One way to check them is with a magnetic compass like boy scouts use.  Hold it near each wheel and have someone pull the pin from the break-away switch, and put it back in.  The needle on the compass should move.  Do this for each wheel.  If the compass needle doesn't move, the magnet in that wheel is bad and needs to be replaced.