2 Quick questions RE: charger/monitor operation

[J Ron]

TV alternator only keeps TT battery up and doesn't figure into battery use in TT. When stopped overnight or other long periods the cable to TT should be unplugged at the car, just don"t forget to plug it back in before towing TTAWAY. If TT is left plugged into car for extended periods when engine not running you could run the TV battery down.

[J Ron]

If you are parked and plugged into 110 and TT charger is on you can leave TT cord connected to TV, this will also keep TV battery in good shape.

[Glenn Baglo]

If you camp in the shoulder season, when solar is less efficient, and run your furnace at night ( a large draw ), and then you leave that camp, with a depleted battery, if you run the fridge on DC while traveling you will arrive with a depleted battery, because the tow vehicle can't supply enough power to run the fridge and charge the battery.

[Raspy]

Originally Posted by Glenn Baglo

If you camp in the shoulder season, when solar is less efficient, and run your furnace at night ( a large draw ), and then you leave that camp, with a depleted battery, if you run the fridge on DC while traveling you will arrive with a depleted battery, because the tow vehicle can't supply enough power to run the fridge and charge the battery.

This is why I always run my fridge on propane when away on a trip. And why a dedicated set of charging wires from the TV alternator is better than the small 7 pin wire. TV alternators are often over 100 amp capacity.

The circuit can be automatically disconnected with the use of a continuous duty Ford solenoid that closes when the TV is started. Then a set of welding cable connectors can be used to disconnect the cables near the hitch.

When off-grid, a Honda generator might run for an hour a day to charge the trailer batteries, but the TV could be started for 1/2 hour or less to do the same. It's not a perfect solution, but could be a very good choice for some. One problem with it is that car alternators are not "smart" chargers and their amperage tapers off significantly as the battery voltage comes up. This tends to mean the batteries are often at less than full charge unless the engine is running for a longer time. Not a problem while traveling, just when making up for the previous days use, so the solar option, when timed right, is very useful.

[floyd]

Originally Posted by Raspy

It's certainly true that charging from the TV can be all that is needed. But the conditions must be right for that to be true. With one battery, the use will probably require daily recharging. So the TV will need to be connected and running long enough every day to accomplish this. Later, after the trip is over, or if someone wants to travel less, the daily TV charging will become a problem. So if a battery charger is going to be installed anyway, it's probably best to size it to do the job entirely itself and not expect to use the TV as a significant charging source that makes up for a too small charger. The TV will likely, in the long run, be a supplemental source.

However, I'm beginning to think a very good charging plan is to have a set of high amp wires dedicated to charging the trailer battery. These would come directly from the alternator and be connected to the trailer battery. This would charge much faster than the 7 pin connector or a Honda generator. And it would mean the generator and it's fuel didn't have to go along on the trip. This is essentially what is done on cruising boats and it works well, especially if the alternator output can be adjusted.

Solar, at least in my case won't be mounted on the roof of my Oliver. So I don't have to park, and don't intend to park in the sun to make it work. Like you, I want to park in the shade. A portable solar system, or suitcase system, is the best for my use. Hopefully the solar can produce enough to carry the load when the trailer does not have shore power and won't require the TV to be used just to charge batteries.

I have a 29 battery (overkill) and just about every possible option on my trailer.
I never bother with 12V on the fridge, but if I don't need the furnace, we can easily go 3 to 4 days boondocking. Of course both the fridge and the furnace are battery hogs so we carry our propane buddy heater as a backup on our annual February trip to Florida(from N. IllAnnoy) but we haven't used it yet...
If its too cold we just keep movin' South 'til it ain't!
You are right it is supplemental , but enough to easily cover those underway nights at Walmart with lights, a hot shower, a movie, and plenty of power for the furnace or the fantastic fan.
For staying two weeks I like having shore power.
I certainly agree with using the TV instead of a Genset, unless you want enough 110V to run your A/C.
I have a couple of friends who have that suitcase solar and it looks really nice, my first thought was theft (unlikely) if you need to place it too far from the trailer. At least it is quieter than a genset, lighter and smells better too!
but then there's that A/C thing again when needed.

[Jann Todd]

Originally Posted by Borrego Dave

Hi Judy, just a couple things for you from my 30+ years RVing and I'm not knocking any others suggestions/comments here. I quit using any deep cycle batteries maybe 25 years ago and started using a standard car type battery, 24 or 27 because the charge time was so much less than a deep/marine cycle battery. These were all in class Cs or A motorhomes with no LED lights or TVs ect. On trips of 2 weeks boondocking I would run the engine for about 15 minutes every 3rd day to charge it up and never had a problem with power. But back to your TT. Charging your TT battery while on the road is going to be determined by the tugs alternators output and the gauge of the wire going back to the TT with a 7 pin plug. If I remember correctly, you're new to RVs, toss a battery in it, go out and go camp. I can guarantee there's not one person here that didn't do a lot of learning a long the way .

Car batteries are not made to be discharged over and over. They are high output for starting a vehicle but not for constant drain like in an RV. Deep cycle batteries are made to be discharged over and over and for constant draining. Car batteries will die quicker eventhough they will charge faster.

[gordon2]

After reading the last ten or so replies, one thing keeps coming to my mind. I Previously mentioned it very briefly but I did not elaborate. A battery monitor that uses a shunt can tell you how much power is coming out of the battery (or has come out), and how much is going back in, or has been put back. It measures the power usage of everything on your camper so you don't have to, and it cares not what the charging source is, converter, solar, tow vehicle, generator etc. It simply measures the load and the charge going into the battery from any type of charger. It greatly helps you to manage the limited resource called battery power. Managing this resource is critical to making sure you have power for what you need, and when you need it. And it can be invaluable assistance in figuring out the weak link in the system; be it the battery size, solar capacity, etc.

The one I use is the TriMetric Model Descriptions - Bogart Engineering and while I love it, and I enjoy the extended functionality that it provides (including integration with the companion solar controller), I have been told that it is overkill for most small trailer owners and I cannot really disagree. IMHO any battery monitor that has real time data is well worth having and one that also provides cumulative recording is ten times better.

(So much for the two quick questions... there is always a great deal more to know about a subject if you wish to pursue it.)

[JC_In_Austin]

Originally Posted by gordon2

After reading the last ten or so replies, one thing keeps coming to my mind. I Previously mentioned it very briefly but I did not elaborate. A battery monitor that uses a shunt can tell you how much power is coming out of the battery (or has come out), and how much is going back in, or has been put back. It measures the power usage of everything on your camper so you don't have to, and it cares not what the charging source is, converter, solar, tow vehicle, generator etc. It simply measures the load and the charge going into the battery from any type of charger. It greatly helps you to manage the limited resource called battery power. Managing this resource is critical to making sure you have power for what you need, and when you need it. And it can be invaluable assistance in figuring out the weak link in the system; be it the battery size, solar capacity, etc.

The one I use is the TriMetric Model Descriptions - Bogart Engineering and while I love it, and I enjoy the extended functionality that it provides (including integration with the companion solar controller), I have been told that it is overkill for most small trailer owners and I cannot really disagree. IMHO any battery monitor that has real time data is well worth having and one that also provides cumulative recording is ten times better.

(So much for the two quick questions... there is always a great deal more to know about a subject if you wish to pursue it.)

Thanks; just saw this. And boy, are you right ~ the information load is incredible, but I'm climbing that hill and I appreciate every response!

[John in Michigan]

Judy,

Checking your registry, you have a 2015 Scamp 13. Does your camper have a built in converter? If so, the converter probably includes a battery charger. If so, you shouldn't need a separate battery charger.

-John

[JC_In_Austin]

Originally Posted by John in Michigan

Judy,

Checking your registry, you have a 2015 Scamp 13. Does your camper have a built in converter? If so, the converter probably includes a battery charger. If so, you shouldn't need a separate battery charger.

-John

Yes, it has a PD9130 converter. I discussed this issue with the technician at Scamp. I let him know that the converter is located such that it can't be accessed to add the "Charge Wizard," which monitors the charge to the battery, and is supposed to take the worry out of the whole thing.

He suggested that when buying a new battery (which I was) that I also get a "battery conditioner" (which I did). I got the CTEK automatic 8-step charger. It's low voltage, but I believe after all the discussion in this thread, that it will serve my needs.