TT Power While Driving

[Margali]

We rented a standard TT over the 4th and some issues with it I want to avoid in our build. Even with being plugged in night before, then filled with frozen items the freezer thawed during 5hr drive in Texas heat. It was running in propane model. I lost some meds even with ice packs. It was also extremely hot to enter and use the restroom.

DH says we can get a bigger alternator for the Ram 1500 and run the AC and fridge without issues. Does that work? I am looking at 8K btu ac listed at 5.8A and Magic Chef fridge listed at 1.5A. The Ram currently has a 160A alternator and there is 220A available. We are running a 12V system but not sure how much AH capacity yet.

Any help would be great. I'm a mechanical engineer not EE. This is Greek to me.

[flboy]

Not sure what your build plans are, but many ways to solve that problem. I'd recommend a compressor fridge. Many types to choose from special purpose 12vdc fridges to run of the mill dormatory fridges. I run the 4.3 Cu. Ft. Dormatory style qFridge with freezer compartment off of deep cycle batteries and an inverter. Solar cells keep battery charged and batteries sustain overnight. Literally can run in perpetuity as it sets if there was never any equipment failures.

Many ways to charge batteries.. but bottom line is run a compressor fridge off batteries and maintain batteries. Propane fridges work, but are not as efficient nor as controllable.

Just my thoughts.

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[kirkupnorth]

Not sure what your build plans are, but many ways to solve that problem. I'd recommend a compressor fridge. Many types to choose from special purpose 12vdc fridges to run of the mill dormatory fridges. I run the 4.3 Cu. Ft. Dormatory style qFridge with freezer compartment off of deep cycle batteries and an inverter. Solar cells keep battery charged and batteries sustain overnight. Literally can run in perpetuity as it sets if there was never any equipment failures.

Many ways to charge batteries.. but bottom line is run a compressor fridge off batteries and maintain batteries. Propane fridges work, but are not as efficient nor as controllable.

Just my thoughts.

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Completely agree! We're running a compressor "dorm" fridge, too. While we're on the road, it's running off the battery and inverter. If camping where there's no electric, it will continue to run like that. If there's electricity available, we just plug in.

We just completed our first voyage with the finished camper, about -- about a 3+ hour drive. Everything in the fridge was nice and cold, and the freezer compartment stuff was still frozen. Worked out great!

[Padilen]

All I can think of is that little wire that runs back to the RV /TT battery. It use to take a long time if the battery was low to recover.

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[Iconfabul8]

Fridges and inverters and batteries are all good if that is all you are doing, but the OP wants to run the ac as well. In which case, it looks like a generator is the cheapest, easiest, most dependable and best route.

[flboy]

Fridges and inverters and batteries are all good if that is all you are doing, but the OP wants to run the ac as well. In which case, it looks like a generator is the cheapest, easiest, most dependable and best route.

Agree, I'd have the Generator to run the AC and make sure it can charge batteries at same time. I still recommend the batteries and inverter... you don't want to run the generator 24/7 just for the refrigerator nor run the generator while driving.


Solar works for charging the batteries and running the fridge while on the road (assume daylight) and independent of the TV. If I could only have a Generator or Solar... I'd go Generator. Fortunately I have the best of both worlds and some redundancy is nice. Now I just use the Generator to run the AC as needed and a backup for charging batteries when I am in a area that is shaded or etc.

[Margali]

We often drive at night so the kids are quiet and asleep so solar isn't helpful. It sounds like a generator may be way to go. I guess I need to figure battery size next so that they will last for about 2.5hrs before break to run generator.

[flboy]

We often drive at night so the kids are quiet and asleep so solar isn't helpful. It sounds like a generator may be way to go. I guess I need to figure battery size next so that they will last for about 2.5hrs before break to run generator.

They do make devices to charge the batteries from your tow vehicle as you drive that are very nice, relatively easy to install, and will do what you need while driving whether day or night. I will see if I can find a link later and edit to add it on. If I remember, you can also attach a solar cell to the same controller. It is much more than just a battery isolator relay.

When you are at camp, the generator can be run for a few hours to charge batteries.

Edit: this is what I was thinking of from Sterling Power. Can use to charge battery from tow vehicle and also run in a solar panel later if wanted. I think others on this forum have some experience with these controllers which are used also in the Marine world.

Sterling BB1230-12 Volt, 30 Amps - Pro Batt Ultra Battery to Battery Charger https://www.amazon.com/dp/B071DMV7PF/re ... ABb6D7AE24




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[McDave]

I used a relay in the tow vehicle that is triggered by a "keyed" circuit so trailer will only be charged when the engine is running. That way the trailer can't discharge the tow vehicle if you don't unplug it. But your alternator can supply a ton of juice going down the road. You arrive at camp with a cold fridge and a full battery bank. If you use a PD-4045 or WFCO 8955 power center for the trailer you will be able to recharge battery bank and power 12v and 120v appliances anytime you have shore power or generator power. Plus they have all the circuit breakers and fuses you will need. You will need a separate charge controller for the solar power.

McDave

[troubleScottie]

Just a note on wire size. The power/ground pair in a 7 pin trailer connector is generally too small to effectively charge the battery and/or run appliances.

You would be wise to run a separate pair of cables -- something to handle at least a 20A load. I cannot recall the gauge. Most likely something between 4 and 8 gauge depending on the length. Think big audio amplifier power cables. There are charts with the load and length and gauge to reduce loss of potential.

The TV to trailer connection is often an Anderson connector. Nice solid connectors, idiot proof. Again, look around. Lots of variants with covers, attachment points, handles, etc

As stated before, this can/should be keyed ie add an solenoid to allow charging when the engine is on. Also remember fuses.

Obviously this cable has to go all the way to your battery/charging system. Retro fitting might be a chore. That might mean creating at least one hole into the trailer. Probably do not want to have this cable in the living space.

If you browse the electrical section, there are numerous discussions on how to connect to charge your battery. Everything from a direct connection, relays, ACR and DC to DC chargers. The technology is improving. As is mentioned above, some serve both solar and vehicle charging. Your design is generally only limited by your pocket book.



As to heat in the trailer as the OP noted, you are going to have to trade off power usage versus comfort. Most teardrops are too poorly insulated to stay cool ( or warm) Assuming shore power, not really a big issue. Just keep the AC, heater or fans on.

Without shore power, you have to realize the fans are a fairly big power draw especially if running 24x7. AC is most likely completely out unless you have a lot of AH to burn and a good recharging system. Shade and open windows/doors are your real friends.

[Margali]

How good are the MaxxAir vents at pulling stale overheated air out of camper? They looks to be much easier on power budget.

The scenario Im trying to figure out temp control for: Cruising down road with it 95F or so and much hotter in camper. Baby or toddler wakes up screaming for diaper change/feeding and set off the other one. Cycling both littles into camper for diaper change let along breastfeeding stop leaves me feeling like crap from heat in camper.

[Florida Native]

When we had little ones, the wife would breastfeed in air conditioned car. Diaper changes were done in or on trunk. No need to go in trailer (maybe for diaper change in rain?).

-Mike

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[flboy]

How good are the MaxxAir vents at pulling stale overheated air out of camper? They looks to be much easier on power budget.

The scenario Im trying to figure out temp control for: Cruising down road with it 95F or so and much hotter in camper. Baby or toddler wakes up screaming for diaper change/feeding and set off the other one. Cycling both littles into camper for diaper change let along breastfeeding stop leaves me feeling like crap from heat in camper.

I see your dilemma now on the heat in the camper while traveling.

The Maxxair will do a great job of pulling in air, but best case, it will be same as outside air. It will clear the air at about 900CFM on high.. so very quick.

When you stop for the baby break, crank up a generator, run the Maxxair with windows open to clear the hottest air, then crank the AC on. After inside temp at parity, close windows and turn off Maxxair and give the AC time to work.

In this case and need, get a big 13.5KBTU roof unit as it will chill it quickly (assuming a smaller CTC).

Need a 3,500W Inverter Gen to run it or spend about $299 on a soft start circuit and it then shoud start and run on a small 2,000W generator. In any case, a 3,500W Honda will be very quiet and do the job and not annoy people at rest stops.

No easy way to travel with small children. I have done it myself. Drive at night and many stops during the day. They will get tougher as time goes on. They effort early on is totally worth it, I might add. My kids have been mostly a joy for me. Just a few teenage years I could have done without. Lol.

Btw.. My wife did all the baby stuff in the car/van with AC on while on the road.



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[Margali]

So we have the five of us in a Ram1500 crew cab. Super tight quarters espcially with 6yr still in booster.

It sounds like Maxx Air will do the trick. I can hop out, open door, and turn on fan before grabbing kids. That should give time to flush out the stale, super hot air. I'm okay with outside temps just not the super baked air. If that doesn't work, then we will look at generator. Thanks guys!

[flboy]

So we have the five of us in a Ram1500 crew cab. Super tight quarters espcially with 6yr still in booster.

It sounds like Maxx Air will do the trick. I can hop out, open door, and turn on fan before grabbing kids. That should give time to flush out the stale, super hot air. I'm okay with outside temps just not the super baked air. If that doesn't work, then we will look at generator. Thanks guys!

Yes, if you do that with the Maxxair to pull air through and have another portable fan to keep air moving around inside the trailer , you should be fine. I do that sometimes when I don't want to turn on the generator and AC and it is acceptable.

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