Battery thoughts/help!

[Darral T.]

Ahhh...you present yet ANOTHER scenario! Yes, then I would get one of my lil recommended devices...paint a picture of a CHICKEN on it. Then when you're asked how you maintain your battery, simply say, "Well, with a 'chicken Tender'!" Ok...poor joke.

But I see a lil "Battery Tender" (or equal) in your future. Alot of people take their battery out of the RV and bring it into a garage or somewhere out of the extreme cold and keep it charged. I've had mine outside in 5 deg weather without hurting it, but I make sure it's fully charged-- this was pre-Battery Tender.

Originally Posted by ScamperGirl

I would love to keep my Scamp at home but alas, my HOA doesn't allow campers in the driveway and I can't store it in the garage (AC unit on top). So, for me, perhaps in between outings but especially in the winter, I'll have to bring the battery home with me.



You are doing something right! That's why I want to learn what to do before buying a new one!

[stevebaz]

Originally Posted by ScamperGirl

In my scenario, when not attached to the TV, none of the lights work. When attached to the 7-pin connection on the TV, the lights work. Are you saying that the lights could work but the battery not be charging (assuming I had a good battery)? Is this something I can test with my new battery tester?!

Take your battery checker and test the battery in your tug. Write down the voltage. Now start your tug and while running check the tugs battery voltage. Now turn off your tug.write down the running voltage.

now take your meter and check the battery voltage on the trailer battery. Write down the voltage. Now hook up the trailer to your tug and connect the wiring. Now start your tug. Now check the battery voltage at the trailer. Write down the running voltage at the battery in the trailer. Have some one rev the motor some in your tug while you check the battery voltage at the trailer battery again. Write down that voltage.

What your measurements should see tug battery 12.5 to 12.75 volts. Tug running 13.5 to 14 volts. Trailer battery your 10 volts. Trailer battery hooked up to running tug over 13 volts. Trailer battery with engine running revved up some closer to 14 volts. If you don't get close to these voltage you will not charge your battery while your towing. If you do this test with the fridge on at 12 volts while you drive and can't maintain battery voltage over 12.7 volts wit the engine running then you are also draining your battery while driving.

[Fallon]

A battery tender & smart converter will be redundant. A 3 or 4 stage converter will do the same trickle charging when the battery is full thing your battery tender will and do bulk charging when needed. An older dumb converter that just puts out a set voltage all the time will either under or over charge your battery depending on the voltage it is set to.

Also, you are fine using power when using a battery minder. Think of your battery like a big storage tank or swimming pol. The battery tender would be filling it with a garden hose & using power (fan, light, etc.) would be draining it with another hose at the same time. Water (charge) level will fluctuate a bit depending on the capacity of your battery tender & load you are using, but it will work fine with light RV type loads. Trying to start a car on a dead battery with a battery tender wouldnt be a good idea though.

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[John Linck]

I watch my single group 29 battery's condition with a digatal volt meter mounted next to the water pump switch. It is charged via tow vehicle and solar panel, and rarely from the charge wizard controled converter since I seldom plug in. My charge line from the tv is fused with no relay, though I always unplug the 7 wire connection when camped. During long term storage in my garage (purpose built 10 foot door) the shore power is unplugged and I use a battery minder. On trips I often run the frig on 12 volts while towing and this requires immediate switch over when stopped for the day. All lights are LED. The furnace is the only significant electrical draw. When not using it the battery will go for at least a week before it hits 50% charge without any charging. If the sun shines with no tree canopy the battery is fully charged each mid afternoon, much earlier in Summer. During cloudy cold weather stationary camping the battery hits 50% on day 3 or 4 almost entirely due to furnace draw.

[ScamperGirl]

Originally Posted by stevebaz

What your measurements should see tug battery 12.5 to 12.75 volts. Tug running 13.5 to 14 volts. Trailer battery your 10 volts. Trailer battery hooked up to running tug over 13 volts. Trailer battery with engine running revved up some closer to 14 volts. If you don't get close to these voltage you will not charge your battery while your towing. If you do this test with the fridge on at 12 volts while you drive and can't maintain battery voltage over 12.7 volts wit the engine running then you are also draining your battery while driving.

Thanks so much! I'll try to get to my storage facility this weekend to get these benchmarks.

Originally Posted by Fallon

An older dumb converter that just puts out a set voltage all the time will either under or over charge your battery depending on the voltage it is set to.

Also, you are fine using power when using a battery minder. Think of your battery like a big storage tank or swimming pol. The battery tender would be filling it with a garden hose & using power (fan, light, etc.) would be draining it with another hose at the same time. Water (charge) level will fluctuate a bit depending on the capacity of your battery tender & load you are using, but it will work fine with light RV type loads.

I have an older 'dumb' converter. Let's say I purchase a battery minder only and attach it to my battery. When my Scamp is plugged in to shore power, will the battery minder help maintain the battery even as the dumb converter tries to under/over charge the battery? Does the battery minder need to also be plugged in or will it work with the shore power coming through the dumb converter? Or in this scenario, would I still need the Wizard to prevent under/over charge by the dumb converter when plugged into shore power and the battery minder - plugged into an outlet at home - for when the battery is stored in my garage?

I do a lot of summer camping in the South and shore power is a necessity for the air conditioner!

[rdickens]

Jenny,

I read through this very quickly and may have missed the answers to the following questions.

Does the battery charge up to something more than 10v when connected to 110v "shore power"? Test it immediately after powering with 110v for several hours.

Does the battery charge up when hooked to tow vehicle 12v for a while (I.e. driving down the road)?

Will the battery take a charge when you open the battery box top and connect the battery to a home charger? (If not, you may have a dead/shorted-out cell and will need a new marine/deep-cycle battery. Floyd gets his at Wal-Mart. Don't get a regular "car" battery.)

Have you checked that the 3-prong cord is plugged into the PDU under the seat?

Have you checked each of the fuses? (IIRC one of the top 2 fuses in mine is the charging circuit.)

I have seen battery charging problems from a bad/blown fuse and from that plug vibrating loose while driving down the road.

Later, I can tell you about solar solutions if you want ....

Good luck! 😊

Ray


Sent from my iPad using Fiberglass RV

[ScamperGirl]

Originally Posted by rdickens

Does the battery charge up to something more than 10v when connected to 110v "shore power"? Test it immediately after powering with 110v for several hours.

I haven't checked this yet with my new battery tester but I would say no based on past evidence. When I left for Florida the battery worked - i know this because the outside light worked when not connected to the TV or to shore power - but I have no idea of the amount of juice that was in the battery before I left. After camping for a week in Florida, connected to shore power the entire time, my battery didn't work when I arrived home.

Also, we camped the last weekend in August and were connected to shore power the whole time. When we arrived home, the outside light didn't turn on.

Again, this is all speculation as I only recently purchased my battery tester and haven't performed any benchmarks when actually camping.

Originally Posted by rdickens

Does the battery charge up when hooked to tow vehicle 12v for a while (I.e. driving down the road)?

I had assumed so until the Florida trip. Steve gave me instructions on how to test this which I will report on once tested!

Originally Posted by rdickens

Will the battery take a charge when you open the battery box top and connect the battery to a home charger? (If not, you may have a dead/shorted-out cell and will need a new marine/deep-cycle battery. Floyd gets his at Wal-Mart. Don't get a regular "car" battery.)

I do not have a home charger at this point. I'm trying to decide between a Charge Wizard attached to the converter, a battery minder attached directly to the battery, or both (wizard to use when connected to shore power; minder to use when battery is stored in my garage)

I'm still trying to understand if the battery minder will protect my battery from under/over charge when the Scamp is connected to shore power through the converter.

Originally Posted by rdickens

Have you checked that the 3-prong cord is plugged into the PDU under the seat?

PDU? Is that the converter? I will double-check this, hopefully this weekend.

Originally Posted by rdickens

Have you checked each of the fuses? (IIRC one of the top 2 fuses in mine is the charging circuit.)

No, I plan to check these fuses this weekend (if I can get to the Scamp)

Originally Posted by rdickens

Later, I can tell you about solar solutions if you want ....

Thanks Ray, that would be great! Just as soon as I get my battery woes under control...

[Fallon]

Originally Posted by ScamperGirl

I do not have a home charger at this point. I'm trying to decide between a Charge Wizard attached to the converter, a battery minder attached directly to the battery, or both (wizard to use when connected to shore power; minder to use when battery is stored in my garage)

I'm still trying to understand if the battery minder will protect my battery from under/over charge when the Scamp is connected to shore power through the converter.

PDU? Is that the converter? I will double-check this, hopefully this weekend.

PDU = Power Distribution Unit. Usually part of a converter.

A smart converter like a PD 4045 is going to be your best way to go (It's always highly recommended around here). It's a 4 stage "smart" charger (what you seem to be calling a charge wizard), a trickle charger or maintainer only has 2 stages, maybe 3. It costs about $200 or so, getting an electrician or RV guy to install it might cost that much again if you aren't electrically inclined. If you aren't electrically inclined, I'd recommend getting a professional to do it as electrical problems can start fires.

It will power your trailer while hooked up at a camp ground, properly charge your battery fully & won't overcharge & boil your battery. If you get the right converter, there is 0 reason to get a battery maintainer or trickle charger, it's just another piece of gear to deal with & will be less capable than a good smart converter.

If you let a battery get below 50% charge it seriously degrades it's performance & lifespan. If it happens several times like it sounds like yours might have, your battery is probably toast or close to it.

[rdickens]

Jenny,

From the lack of light functionality and from your voltmeter test, it seems certain that your battery is currently completely discharged.

What caused the discharge, why the battery hasn't recharged on 110v or 12v, and whether any damage has been done to the battery all seem uncertain to me.

In the other thread you referenced (Never a Thought?), IIRC Carl found his 3 - pronged cord unplugged.

On our trailer, we have used 110v "shore power" for extended periods of time at the LBL rally, at Scamp Camp (Sebring, Fl), and many other places during cross country travels. I don't think we've ever "boiled our battery" or otherwise damaged it from week-long connections to 110v power. Leaving the trailer plugged into 110v all winter long might be another matter altogether?

When our charging circuit fuse was blown (probably during the addition of a new interior 12v outlet), we did completely discharge the battery. Accidentally leaving the refrigerator set on 12v overnight (at a WalMart parking lot) also discharged the battery one time.

You really need to make sure that, measured with your voltmeter at the battery terminals, you are getting an adequate charging voltage when plugged into 110v power or from the 12v line from the tow vehicle.

Then, especially if your battery won't hold a charge, have the battery checked for shorted-out cells or its general condition/health. As mentioned, many places will test your battery for free.

Once it is all working and/or tested, you can decide on a possible new marine (deep cycle) battery, a new converter/PDU, and/or a battery wizard/tender etc.

Good luck! ☺

Ray

Sent from my SCH-I545 using Fiberglass RV mobile app

[rdickens]

Jenny,

I am assuming that you will be able to find and resolve your charging and/or battery issues this weekend.

We store our trailer indoors, so our use of solar is simply for boondocking/dry-camping.

If you trickle charge your battery all winter (whether at home and off the floor on some 2x4s or at the storage facility), you should use some sort of desulfator battery minder/tender/wizard ..... or possibly the 12watt solar panel solution.

In the later part of this thread are some links to interesting solar discussions.
http://www.fiberglassrv.com/forums/s...ad.php?t=71251

Again .... Good luck! 😊

Ray


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[floyd]

A good fully charged battery with a clean and covered top will sit for months without losing significant charge.

Charge the battery,disconnect the terminals, clean the top and cover it with something like a shower cap.

[ScamperGirl]

So I was able to check a few items yesterday on my Scamp.

Originally Posted by rdickens

Have you checked that the 3-prong cord is plugged into the PDU under the seat?

Yes, the cord was plugged in.

Originally Posted by stevebaz

What your measurements should see tug battery 12.5 to 12.75 volts. Tug running 13.5 to 14 volts. Trailer battery your 10 volts. Trailer battery hooked up to running tug over 13 volts. Trailer battery with engine running revved up some closer to 14 volts. If you don't get close to these voltage you will not charge your battery while your towing. If you do this test with the fridge on at 12 volts while you drive and can't maintain battery voltage over 12.7 volts wit the engine running then you are also draining your battery while driving.

My benchmarks were:
Tug: 12.42
Tug running: 14.20
RV Battery: 9.14
RV Battery attached to tug: 9.14
RV Battery attached to revving tug: 9.14

Uh, oh... something is wrong. Turns out the fuse on the outside of the battery is broken. So there's one mystery solved. I went into the Scamp and pulled the #3 fuse from the panel to use as a tester. I replaced the bad fuse and attached the tug again. 8.67. What?!? It occurred to me that perhaps I should try again with a different fuse from the panel. So I replaced the #3 fuse and pulled the #2 fuse. Attached the tug and now saw:

with fuse replaced, attached to tug: 12.21
with fuse replaced, attached to revving tug: 12.44/12.66

So the battery never gets up to the 14.xx as recommended to charge the battery while driving, even with the good fuse. I do plan to take the battery to a professional to be tested. Is the battery itself preventing the charge from going up to the recommended 14.xx?

I searched and searched for the elusive 2nd fuse inside the Scamp (passenger side under bench storage). I saw lots of wires coming in from the battery and a lot of black tape covering the wires but no fuse. I pulled back some of the rat fur and still no fuse. Then I got to thinking:

Originally Posted by rdickens

Have you checked each of the fuses? (IIRC one of the top 2 fuses in mine is the charging circuit.)

Could it be that the secondary fuse is in the #3 slot on my fuse panel? And that's why when I pulled that fuse I still didn't see a charge in the 12.xx range? Ray, is that what you meant by "one of the top 2 fuses in mine is the charging circuit"? I hope so because I don't want to have to pull away too much of the rat fur to search for a fuse that isn't there.

[ScamperGirl]

Originally Posted by Fallon

A smart converter like a PD 4045 is going to be your best way to go (It's always highly recommended around here). It's a 4 stage "smart" charger (what you seem to be calling a charge wizard), a trickle charger or maintainer only has 2 stages, maybe 3. It costs about $200 or so, getting an electrician or RV guy to install it might cost that much again if you aren't electrically inclined. If you aren't electrically inclined, I'd recommend getting a professional to do it as electrical problems can start fires.

I did look at this one but I already have a converter and a panel and I'd like to avoid the cost of replacing all of the electrical in my Scamp (I thought about doing it myself until I took a thorough look at the panel and converter. Way above my level of expertise!). I was hoping to get something like this: Amazon.com: Progressive Dynamics PD9105V Lead Acid Battery Charge Wizard: Automotive that I could just plug into my converter. I have an Intelli-Power 9100 Model PD9130

Has anyone used one of these?

[steve dunham]

In my old.Scamp ,the charging portion of my converter went bad . I disconnected the charging section of the converter and tied in a smart charger implace of the converter charger. This was easier, cheaper and worked well . The 4 stage charger did a better job of
charging / maintaining the battery than the original converter charger. The battery was 5 years old when I sold the trailer and still tested okay

[rdickens]

Jenny,

When you replaced the fuse and the battery terminal voltage went from 8.#-10.# to 12.#, you almost certainly have solved the problem. 😀

Because the battery is/was so completely discharged, it is very likely pulling down the charging voltage from 13.# to 12.#. Once the battery is again fully charged, you will likely see higher voltages when connected to the tow vehicle or to 110v shore power.

I would now plug the trailer into 110v (for a half a day or so), verify the starting voltage at the battery terminals, test the voltage periodically during the charge cycle, and test at the end of the charging cycle with 110v still plugged in and again with 110v unplugged.

You could then repeat your tow vehicle tests if you want to.

Then get the battery tested for shorted cells and make sure it will "hold a charge" when not attached to the trailer.

When you reattach the battery to the trailer cables, look for any possible power drains within the trailer (I.e. A light or water pump inadvertently left on.)

Then, I'd suggest going out and get replacement fuses and spare fuses of every size used in the trailer. (I hear that they even have fuses that light up to show whether they are blown or not.)

If you are getting adequate charging voltage (with a fully charged battery) from both 110v and 12v and your battery tests good, you might possibly be overthinking the battery minder/tender/wizard things? Those things are valuable and have their place, but they might not be an immediate need?

Good job of troubleshooting! Well done! 😀

Ray






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[Fallon]

Originally Posted by rdickens

Jenny,

When you replaced the fuse and the battery terminal voltage went from 8.#-10.# to 12.#, you almost certainly have solved the problem. 😀

Because the battery is/was so completely discharged, it is very likely pulling down the charging voltage from 13.# to 12.#. Once the battery is again fully charged, you will likely see higher voltages when connected to the tow vehicle or to 110v shore power.

If your battery ever drops below 11 volts (to some degree even under 12) you are causing serious longterm damage to it. You never want to drop a deep cycle battery below 50% charge of you will cause damage to the plates. Your standard car battery gets damaged at even lesser rates of discharge.

[rdickens]

I must confess that I have heard the "never discharge below 50%" rule often repeated and I guess that I maybe I don't quite fully understand it.

I have long thought that marine deep-cycle batteries were designed for use with electric trolling motors and were built to be repeatedly 80% discharged down to to about 20% of their capacity.
(I am truly not wanting to be contrary or argumentative. I really don't understand. &#128543

In one of the later segments of the solar thread that I referenced, there is a reference to something called "The 12 Volt Side of Life". It seems to be well written and discusses all sorts of batteries (flooded cell, Gel, AGM, deep cycle, etc.)
http://www.marxrv.com/12volt/12volt.htm
http://www.marxrv.com/12volt/12volta.htm

From that article, I understand that it is not a good practice to "REGULARLY consume more than 60%" of your battery's capacity and that the more times that you really deep cycle the battery, the shorter it's useful life will become.

That said, I have never been sure how much damage might really be done to a good marine deep-cycle battery by an occasional inadvertent deep cycle. Does it vary by brand?

I really regret the couple of times that I have inadvertently discharged my battery, but it still seems to be quite functional ..... knock on wood. I suppose that I really should go get it professionally tested sometime soon.

If it tests OK, am I still supposed to preemptively replace it?

I do try to keep track of my battery status on a somewhat regular basis. (I have meters that measure my battery voltage, both the voltage and amperage supplied by my solar panel, and/or the amperage drawn from my trailer appliances - i.e. fan, water pump, lights, etc.)

Just wondering ....... 😕

Ray




Sent from my iPad using Fiberglass RV

[Fallon]

Originally Posted by rdickens

I must confess that I have heard the "never discharge below 50%" rule often repeated and I guess that I maybe I don't quite fully understand it.

I have long thought that marine deep-cycle batteries were designed for use with electric trolling motors and were built to be repeatedly 80% discharged down to to about 20% of their capacity.
(I am truly not wanting to be contrary or argumentative. I really don't understand. &#128543

In one of the later segments of the solar thread that I referenced, there is a reference to something called "The 12 Volt Side of Life". It seems to be well written and discusses all sorts of batteries (flooded cell, Gel, AGM, deep cycle, etc.)
The 12volt Side of Life (Part 1)
The 12volt Side of Life Part 2

From that article, I understand that it is not a good practice to "REGULARLY consume more than 60%" of your battery's capacity and that the more times that you really deep cycle the battery, the shorter it's useful life will become.

That said, I have never been sure how much damage might really be done to a good marine deep-cycle battery by an occasional inadvertent deep cycle. Does it vary by brand?

I really regret the couple of times that I have inadvertently discharged my battery, but it still seems to be quite functional ..... knock on wood. I suppose that I really should go get it professionally tested sometime soon.

If it tests OK, am I still supposed to preemptively replace it?

I do try to keep track of my battery status on a somewhat regular basis. (I have meters that measure my battery voltage, both the voltage and amperage supplied by my solar panel, and/or the amperage drawn from my trailer appliances - i.e. fan, water pump, lights, etc.)

Just wondering ....... 😕

It's not a hard & fast thing, but going below 50% does decrease it's capacity & lifespan. There is no reason to replace a battery that if functioning properly & still has adequate capacity. Adequate capacity may mean different things to different people though.

Deep Cycle Battery FAQ vs Life
Battery life is directly related to how deep the battery is cycled each time. If a battery is discharged to 50% every day, it will last about twice as long as if it is cycled to 80% DOD. If cycled only 10% DOD, it will last about 5 times as long as one cycled to 50%.

Different sources will state different details or formulas, but the deeper the discharge the worse it is for the battery.

Voltage isn't actually that great a way to determine how charged your battery is. You need a meter to measure how many amps you stuff into the battery & how many you pull out to do it properly. Personally I use a TriMetrics TM-2030 which runs a hair over $170 with the proper shunt & wiring. My next step is another $120 for the solar charge controller & some panels.

If you really want to go down the rabit hole about battery charging (and solar) look up HandyBob. He rant's a lot & is generally a bit angry, but definitely knows his stuff about batteries, charging them & solar. It's a great place to learn a lot.

[rdickens]

Much of the information in the Deep Cycle Battery FAQ seems very similar to the information in "The 12 Volt Side of Life".

The volt/ammeter that I use in our airplane is an E.I. VA-1A and is about twice the cost of the Trimetrics TM-2030. In the event that I ever lost the
alternator while in flight, it would help me with "load shedding" (shutting off all non-essential loads in order to conserve battery power until I could
safely land the airplane).

The voltmeters and volt/ammeters that I use for the trailer are considerably
less expensive ...... but then my life doesn't depend on those.

Ray

[ScamperGirl]

Originally Posted by rdickens

Jenny,

When you replaced the fuse and the battery terminal voltage went from 8.#-10.# to 12.#, you almost certainly have solved the problem. 😀

Because the battery is/was so completely discharged, it is very likely pulling down the charging voltage from 13.# to 12.#. Once the battery is again fully charged, you will likely see higher voltages when connected to the tow vehicle or to 110v shore power.

I would now plug the trailer into 110v (for a half a day or so), verify the starting voltage at the battery terminals, test the voltage periodically during the charge cycle, and test at the end of the charging cycle with 110v still plugged in and again with 110v unplugged.

You could then repeat your tow vehicle tests if you want to.

Then, I'd suggest going out and get replacement fuses and spare fuses of every size used in the trailer. (I hear that they even have fuses that light up to show whether they are blown or not.)

My next scheduled trip is the weekend of October 2nd. I will run another set of benchmarks before and after hooking up to power for the weekend. Hopefully my battery will be able to fully charge.

I will also stock up on fuses before that trip.

Originally Posted by rdickens

Then get the battery tested for shorted cells and make sure it will "hold a
charge" when not attached to the trailer.

Most certainly!!

Originally Posted by rdickens

Good job of troubleshooting!

Thanks to you and everyone else who helped me!!

I'll post an update in this thread after my October trip.