Plan for Lithium and Solar upgrade

[daleyocum]

Originally Posted by Chuck Bye

I have a 25FBT with 180 watt solar and two Air Conditioners on order and would like to have the best electrical upgrade so I do not need to start making upgrades upon delivery. My dealer and airstream customer support are of no help and I do not know how to contact Airstream engineering for competent answers. I know nothing about electricity. It seems I will need an upgrade to a premium 2000 watt sine inverter (retail cost $200), a 2000 watt CONVERTER (retail cost $200) 2 gauge wiring on trailer, heavy gauge wiring to tow vehicle, modified monitor and dealer installed solar batteries with some type of sticker. (no one at the dealer or airstream knows anything about the POWER PLUS OPTION and what are the pros and cons.)
Some marketing from airstream says I am buying a 6 sleeping unit with 3 way refrigerator and others say 4 person with only two way refrigerator. Which is it?
Wisconsin Chuck

I sure wouldn’t get their older 180watt solar option, it’s very expensive for what it is and uses less than optimal parts. The Airstream Power Plus option is the best Airstream itself offers and it’s not bad. I don’t know the price, though. I think it’s a dealer installed option. If you can get the factory to do it I’d feel better than a dealer who gets to learn on the job with you as the first victim. I would be covered by the Airstream warranty.

You can do better than Power Plus with the kind of high end systems some of us have installed but installers who know how to do this are rare. GMFL on this forum is one. Lewster here is one. AM Solar in Oregon is another. Any change like this will all likely compromise your electrical warranty for what it’s worth.

Technically you can sleep six in your unit but it would be a miserable experience. Four is the practical max. I’m not sure what fridge they are shipping now in the GT. Older ones were 2-way gas/AC but they may be using the newer compressor fridges in the GT now. Those don’t run at all on propane.

[TowmaterATX]

Originally Posted by switz

When using a male 50 amp plug pigtail with a 30amp power cable connection on the other end, only one of the 50 amp legs is connected. Joining the two 50 amp wires together would trip breakers

It is true that you can trip breakers at the pedestal if you draw more than the 30A can supply when using a 30A to 50A adapter. But they are wired so that both hot leads on the 50A are tied to the hot on the 30A. That is why everything (both sides of your 50A lines) work when your on an adapter. If you pull more than 30A then it will pop the breaker on the pedestal. Here is a picture of how they are wired.

[TowmaterATX]

Just wanted to post an update. Got the trailer. It's really nice and was in very good shape. A few minor blemishes on things like trim glue seeping etc.. but overall in great shape. Need to get it out for a camping trip to really test everything.

I installed both of the micro-air soft starts today. The instructions from micro-air were exactly as I found the ACs. This is a 2021GT25FBT. There was a control board and a start capacitor just like the instructions call out. And they have everything setup for you to integrate the microair into that setup.

Hopefully the progressive surge protector and my equalizer hitch tomorrow.

[daleyocum]

Originally Posted by TowmaterATX

Just wanted to post an update. Got the trailer. It's really nice and was in very good shape. A few minor blemishes on things like trim glue seeping etc.. but overall in great shape. Need to get it out for a camping trip to really test everything.

I installed both of the micro-air soft starts today. The instructions from micro-air were exactly as I found the ACs. This is a 2021GT25FBT. There was a control board and a start capacitor just like the instructions call out. And they have everything setup for you to integrate the microair into that setup.

Hopefully the progressive surge protector and my equalizer hitch tomorrow.

Good to know, thanks for the update!

[rickst29]

Originally Posted by TowmaterATX

Thanks. Once I get eyes on the trailer I'll figure out if pulling more wire makes sense. The panels I've been looking at are just over 20V and just under 5A at full power. So part of me thinks that a little bit of loss if they are all at 100% vs the potential for more loss in the more common case of partial shading with a series-parallel is a tradeoff that makes sense. But I hear you, if I can run the wires easily... no need to choose.

Instead of wiring all 4 panels in parallel, you can connect 2 panels to each other in series - and then wire the two series "strings" into the Airstream wiring as if they are each 40v panels. Your maximum current would then be 10A (at 40 volts), instead of 20A (at 20 Volts). Much less wiring loss, even with a substantial length of AWG-10 Solar Wire.
- - - -
You could go even more extreme, as I did, and wire ALL your panels as one series string. There would be just one "+" and one "-" wire into the airstream wiring, but it would be running at 80 volts, 5A maximum. I have done the 4 panels on my RV in that way (mine panels are not the same as yours, I have lower total voltage and slightly higher current.)

The chief disadvantage of "all-in-series" is that clouds on one or two panels will hurt the output of the entire group a lot more, than if they were in parallel. Your Victron can easily handle the V (disconnect) in all 3 configurations: 4 parallel, 2 parallel strings of 2 panels each, and all 4 panels in one series "string".

[mythbuster88]

Back to the DC/DC converter thing
We get 12-14 amps into the LiFePO4 battery bank.
This is a good thing over several hours of driving.
Our trailer fun time is in the winter when the days are short, the sun is very low in the sky and with luck some rain.

[qwertyd10n]

Originally Posted by GMFL

Using a DC/DC Charger is a nice addition. The 12/12-9 would work if you were going to just use the black (+) 10awg wire from the 7pin.
I used a 50A MasterVolt DC/DC Charger and ran 2AWG wire from the front of the truck to an Anderson Power Pole Plug and then ran 4AWG from another Anderson Plug to the charger inside the Trailer.
The MasterVolt Charger is programmed ( User Defined) to trigger “ON” when the input voltage is 13V for greater than 30Seconds And turn “OFF” when the voltage drops to 12.7V.

Would the 12/12-9 that you're both referring to be the Victron Orion-Tr 12/12-9A (ORI121210110R)? And it would work to both somewhat charge LiFePO4 batteries off the regular 7-way trailer plug while driving as well as protect the TV charging system?

[GMFL]

Originally Posted by qwertyd10n

Would the 12/12-9 that you're both referring to be the Victron Orion-Tr 12/12-9A (ORI121210110R)? And it would work to both somewhat charge LiFePO4 batteries off the regular 7-way trailer plug while driving as well as protect the TV charging system?

Yes, but it’s a smal DC/DC Charger. There are much better and larger choices out there both from Victron and others from 30A-60A.
This will charge much faster than the 12/12-9 and protect the system all the same.

[qwertyd10n]

Originally Posted by GMFL

Yes, but it’s a smal DC/DC Charger. There are much better and larger choices out there both from Victron and others from 30A-60A.
This will charge much faster than the 12/12-9 and protect the system all the same.

Would you have a recommendation or suggestion on the biggest a person could go on the standard wiring in the 7-way trailer plug versus running a much beefier wire like you recounted earlier in this thread?

[daleyocum]

Originally Posted by qwertyd10n

Would you have a recommendation or suggestion on the biggest a person could go on the standard wiring in the 7-way trailer plug versus running a much beefier wire like you recounted earlier in this thread?

It’s very dependent on what your TV can provide. For example my 2019 F150 was huffing and puffing to get to 10amps.

[switz]

#10 gage stranded copper wire is rated for 30 amps. One could use #8 stranded copper wire that is rated 40 amps as the lead from the battery to the fuse block and then to the seven wire plug on the back of the tow vehicle. That would preclude any voltage drop to that point of the 30 amp power circuit. However, the usual wiring from that point onwards could be much smaller in diameter without making a custom pigtail to the 12Vdc power junction block inside the trailer.

[TowmaterATX]

Just a quick note on progress. This past weekend I was far enough along that I actually reset breakers, flipped switches and turned it all on. So far so good. I'll grab some pictures once I have it all finished.

One thing that was missing from my diagram is the tongue jack. It's wired direct to the battery box in the front with an inline fuse. I reused the inverter positive cable to get the positive lead back into the trailer and tied that into a new 30A bluesea breaker tied to the batteries. I also added a Cerbo GX and have been getting that setup as well. I'll update my wiring diagram and include it when I upload in the pictures.

Still have the solar panels to install on the roof. All of the solar stuff inside is done, but I still need to take care of installing the panels.

I'm contemplating adding a orion tr smart for the 7 way plug. It's 10 AWG all the way from the truck front, but I'm not sure I'll actually be able to pull 30A from it. Also thinking about running a new power run to the back bumper as I've seen others do. But I might just wait and see how things go at this point.

I've had a blast getting all this wired up.

[daleyocum]

My guess is you’ll find, like I did, that your solar panels will completely charge your batteries on driving days. You are wise to put off that 7-pin project until it’s clear it buys you anything.

[Ginophiles]

[QUOTE=TowmaterATX;2421133]

[QUOTE]

First, a level set on the situation. Putting this out there so I have it wrong someone can correct me.

For RVs the 50A shore power connection is actually 2 50A rated line inputs. Red and black in my drawing. The stock panel is also wired to take these two 50A circuits (the double pole 50A main breaker). When you are plugged into 50A shore you could theoretically draw 100A of 120VAC. Our trailers will likely never do that, but when you bump up to 50A you get two lines with the way the industry has gone with the connectors and the standard hookups at the pedestals.

Now, what happens when you put a 30A to 50A adapter on your shore plug? The adapter internally ties the 1 hot line on the 30A side of the adapter to both of the hot lines on the 50A side. This is why when you are on 30A you can still run everything in your trailer if you're careful not to exceed the current limit and pop the breaker on the pedestal. Same thing applies for the 15/20A to 50A adapters, they take the 1 hot line and tie it to both on the 50A side.

I'm just a General Contractor, not an Electrical Contractor, but I've wired a lot of stuff and do not think this is correct. Yes there are 2 hot legs, red and black, but by code they are hooked to a 2 pole breaker. If either leg exceeds 50 amps of draw BOTH poles on the breaker trip. That's why they're tied together. Plus, that would allow 100 amps to run through #6 wire, not good.

I'm sure you know this TowmaterATX, but for others, sometimes it's good to think in watts. The total amount of power available in a giving system or circuit. On 50 amp shore power with ~ 240v we have 12000 watts of power to use (watts=amps x volts). When the 30amp adapter plug is used with the 50 amp trailer plug, it applies 120v to the 2 legs of the trailer panel. So, on 30amps with a 120v we have 3600watts available. Almost 2/3rds less. It's down to 1800watts on a 15amp household circuit.

I was thinking about slapping a couple of solar panels on our rig, but after reading this thread, I'm going to have to step up my game. Looking forward to seeing the pictures of your install.

[susans69]

It takes all that to charge battery will solar panels?

[GMFL]

Originally Posted by susans69

It takes all that to charge battery will solar panels?

It can be a daunting task for some.

[rickst29]

Originally Posted by mythbuster88

Back to the DC/DC converter thing
We get 12-14 amps into the LiFePO4 battery bank.
This is a good thing over several hours of driving.
Our trailer fun time is in the winter when the days are short, the sun is very low in the sky and with luck some rain.

I have modified my TV and Trailer, to accept a lot more amps (and watts) into the LFP battery bank through the Solar controller while the Tow Vehicle is in use). I get about 30 Amps net, at 14.5 Volts. But it's a bit complicated, taking at least 2-3 hours to install.

Under the hood of the 4Runner, under control of a dashboard switch (which you only need for the case of towing "normal" 12v trailers), I run a new battery lead through a 36V regulating boost Converter, good for up to 540 Watts, into the Trailer Battery Charge wire (AKA "TBC").

Then within the Trailer, I have a switching Relay with coil voltage 24v. It detects that TBC Voltage has been increased, far beyond the normal 13.3V value, and directs another Relay to make a change on the Solar Input: instead of using the actual Solar Array, it connects the 36V / 540 Watt TBC as a sort-of-virtual "Solar Panel" instead. (The TBC, instead of connecting into the, gets connected as Solar Panel input.)

Another friend has done this with his Trailer, skipping the dashboard switch (because he never tows anything except the Travel Trailer). He uses a single 5-pin, 24v coil "detector" to switch the Solar Controller input, and leaves the Bargman TBC with no ability to connect at 12v - it goes directly into that switching relay, so the TBC in the Trailer is either 36V into the Solar Controller or nothing at at all (it will never be accepted as a 12v power circuit.) But both of us have the same resulting configuration: While driving the down the road, or when connecting the Bargman to the Trailer for "emergency" charging from TV under cloudy conditions, the Tow Vehicle as used as a single high-power panel, through the MPPT Solar Controller.

Advise by reply or PM if if you want pictures and specific parts required to do this, I may have posted that stuff in a different non-Lithium Thread already.

[rowiebowie]

Originally Posted by TowmaterATX

Just a quick note on progress. This past weekend I was far enough along that I actually reset breakers, flipped switches and turned it all on. So far so good. I'll grab some pictures once I have it all finished.

One thing that was missing from my diagram is the tongue jack. It's wired direct to the battery box in the front with an inline fuse. I reused the inverter positive cable to get the positive lead back into the trailer and tied that into a new 30A bluesea breaker tied to the batteries. I also added a Cerbo GX and have been getting that setup as well. I'll update my wiring diagram and include it when I upload in the pictures.

Still have the solar panels to install on the roof. All of the solar stuff inside is done, but I still need to take care of installing the panels.

I'm contemplating adding a orion tr smart for the 7 way plug. It's 10 AWG all the way from the truck front, but I'm not sure I'll actually be able to pull 30A from it. Also thinking about running a new power run to the back bumper as I've seen others do. But I might just wait and see how things go at this point.

I've had a blast getting all this wired up.

No sparks, no fires. Always a good thing. Congrats.

[rickst29]

Originally Posted by daleyocum

My guess is you’ll find, like I did, that your solar panels will completely charge your batteries on driving days. You are wise to put off that 7-pin project until it’s clear it buys you anything.

100% correct. In my TT, however, the fridge has been "upgraded" to an electrical-only compressor model, and cloudy driving days (or driving at night) were always a "losing" proposition until arriving in camp... with plugins or excellent solar conditions leading to full charge at a later time. People with generators have another option after arrival, but I don't use one.

[TowmaterATX]

Originally Posted by rickst29

I have modified my TV and Trailer, to accept a lot more amps (and watts) into the LFP battery bank through the Solar controller while the Tow Vehicle is in use). I get about 30 Amps net, at 14.5 Volts. But it's a bit complicated, taking at least 2-3 hours to install.

Under the hood of the 4Runner, under control of a dashboard switch (which you only need for the case of towing "normal" 12v trailers), I run a new battery lead through a 36V regulating boost Converter, good for up to 540 Watts, into the Trailer Battery Charge wire (AKA "TBC").

Then within the Trailer, I have a switching Relay with coil voltage 24v. It detects that TBC Voltage has been increased, far beyond the normal 13.3V value, and directs another Relay to make a change on the Solar Input: instead of using the actual Solar Array, it connects the 36V / 540 Watt TBC as a sort-of-virtual "Solar Panel" instead. (The TBC, instead of connecting into the, gets connected as Solar Panel input.)

Another friend has done this with his Trailer, skipping the dashboard switch (because he never tows anything except the Travel Trailer). He uses a single 5-pin, 24v coil "detector" to switch the Solar Controller input, and leaves the Bargman TBC with no ability to connect at 12v - it goes directly into that switching relay, so the TBC in the Trailer is either 36V into the Solar Controller or nothing at at all (it will never be accepted as a 12v power circuit.) But both of us have the same resulting configuration: While driving the down the road, or when connecting the Bargman to the Trailer for "emergency" charging from TV under cloudy conditions, the Tow Vehicle as used as a single high-power panel, through the MPPT Solar Controller.

Advise by reply or PM if if you want pictures and specific parts required to do this, I may have posted that stuff in a different non-Lithium Thread already.

This is very interesting. The voltage boost would reduce the voltage drop on the 10AWG. 15A is very reasonable for the 10AWG. I have the new solar controller right next to the 7-way with the way I've wired it all. This would totally work for me. I could use my upfitter switches in the truck to kick the relay on. I'm very interested in your solution. Sounds like better plan that running some #2 and using anderson connectors at 12-14V to get a similar result. Plus I'd save the money on the Orion.