Best way to use solar w/ shore power

[dquirk29]

Hello,
I just purchased an airstream w/ solar panels. I'm trying to figure out the best way to use all that free/renewable power on our roof. Our rig does not have an inverter (as far as I can tell).

The only way I can think of is to unplug the shore power and use the charged up battery. Is there any kind of switch inside the AS?

Our's is a 2013 30ft signature

Cheers
DQ

[alano]

You should have a battery disconnect switch that's labelled Store/Use. When you're connected to shore power, you should disconnect the batteries and let your converter supply 12 V to your trailer. You solar panels are still charging the battery even in the Store position. The solar charger is a much better charger than your converter, so when connected to shore power, keep in the switch in the Store position and you're batteries will last longer.

When you're boondocking without shore power or when you're travelling and want the fridge to cool, you'll need to select the Use position. This will re-connect your batteries and supply 12 V to the trailer.

Good luck with your new Airstream and ask away if you have more questions.

[dznf0g]

This isn't always true. Some ASes have a battery isolation switch and some have a house isolation switch. My switch disconnects all house circuits from the battery and converter. If the converter is plugged to shore power, the batts are still receiving power, but the house is not. Since my positive busses are upstream from the cutoff switch, solar is always on regardless of switch position. And yes, that configuration is factory. My only change was to move the propane detector from the positive buss to the fuse panel for the house so it's not powered while in storage.

[dquirk29]

All of my outlets still work while I have it in the store position so I assumed shore power was still being used for the fans etc..

Al, just so I understand, you are saying while in store mode the AS is like a giant extension cord for all the outlets and oven?

Thanks
DQ

[dquirk29]

Sorry one more question, until the next one

When I am plugged in on shore power and have the AS in store mode. The batteries on the tongue are charged from the solar panels? Is that correct?

DQ

[RamblinManGa]

Hi from AZ. . . welcome to our group, you ask good, specific questions, keep them coming ! regards, Craig

[alano]

Originally Posted by dznf0g

This isn't always true. Some ASes have a battery isolation switch and some have a house isolation switch. My switch disconnects all house circuits from the battery and converter. If the converter is plugged to shore power, the batts are still receiving power, but the house is not. Since my positive busses are upstream from the cutoff switch, solar is always on regardless of switch position..

This is good to know. What year did AS switch over to the current configuration?

[alano]

Originally Posted by dquirk29

Sorry one more question, until the next one



When I am plugged in on shore power and have the AS in store mode. The batteries on the tongue are charged from the solar panels? Is that correct?



DQ

Correct. In your model the solar charger is connected directly to the batteries regardless of the position of the Use/Store switch.

[dznf0g]

Originally Posted by alano

This is good to know. What year did AS switch over to the current configuration?

I don't know...I assume it is model run driven. I believe the Excellas and Classic 30/31s were like that up to 2015. I don't know if they changed the Classics with the new configuration. Other 30'ers????? I don't know either.

[gsmithii]

Great conversation! It has encouraged me to dig into tha manuals and start measuring voltages.

[Della]

Originally Posted by alano

You should have a battery disconnect switch that's labelled Store/Use. When you're connected to shore power, you should disconnect the batteries and let your converter supply 12 V to your trailer. You solar panels are still charging the battery even in the Store position. The solar charger is a much better charger than your converter, so when connected to shore power, keep in the switch in the Store position and you're batteries will last longer.

When you're boondocking without shore power or when you're travelling and want the fridge to cool, you'll need to select the Use position. This will re-connect your batteries and supply 12 V to the trailer.

Good luck with your new Airstream and ask away if you have more questions.

I have a sub-question based on this conversation, so hope that's not contrary to protocol. I have a '73 overlander 27', and we stay in the summer at a ranch without hookups, so we have a portable solar charger (Zamph?) to keep the battery charged (which works very well by the way). In the winter we keep it at an RV site on the coast (So. Oregon) with hookups. Question is, based on your comments above, should I disconnect the battery all winter while on Shore Power to save battery life?? We do not have any of the finer improvements of switching on or off; we have to physically disconnect the battery cables. If your suggestions is YES, disconnect, then is it necessary to disconnect both positive and negative cables?? Thanks so much !!
Richard

[alano]

rico, sounds like you have a couple of options in Winter if your connected to shore power for extended periods:

1. Best to not let your converter charge the batteries with a single-stage battery charger. So simply disconnect your battery. It's only necessary to disconnect one of the battery terminals and the preferred terminal to disconnect is the negative terminal (if you accidentally short out the negative terminal to the chassis there's no harm done). Some folks remove the negative terminal and wrap it in a latex glove for insulation.

2. Another option if you're connected to shore power for an extended period is to upgrade your converter to a three-stage battery charger. This way battery will not be overcharged.

3. Another option, would be to rewire your trailer as is done in the current AS models such that when the battery disconnect switch is in the Store position, the converter is connected to the main 12 V bus but the batteries are disconnected. In you case the portable solar system would connect directly to the batteries and happily charge the batteries during Winter.

[baterup]

Great Q&A's guys, thanks for the experience...

[WestieHouse]

Great information. After much study I plan to swotch out the stock converter on my 2015 FC 23FB. Does anyone have a recommendation for a particular 3-stage converter? What is approximate cost? Can someone who has average electrical (installing seitches snd fixtures in a house) knowledge do this?

[gecko]

Originally Posted by rico2surf

I have a sub-question based on this conversation, so hope that's not contrary to protocol. I have a '73 overlander 27', and we stay in the summer at a ranch without hookups, so we have a portable solar charger (Zamph?) to keep the battery charged (which works very well by the way). In the winter we keep it at an RV site on the coast (So. Oregon) with hookups. Question is, based on your comments above, should I disconnect the battery all winter while on Shore Power to save battery life?? We do not have any of the finer improvements of switching on or off; we have to physically disconnect the battery cables. If your suggestions is YES, disconnect, then is it necessary to disconnect both positive and negative cables?? Thanks so much !!
Richard

If your solar system has a good three stage converter and you have exposure to sunlight during the winter (you're not stored indoors), the solar system will do a much better job of keeping your batteries nicely topped off and maintained than will the inferior one stage converter/charger supplied with your Airstream.

Disconnecting your batteries entirely during the winter will tend to run them down. Charging through the one stage converter/charger with shore power will tend to overcharge (flood them.) So first check that you do have a three stage charger on your solar system. If it's an Airstream supplied system, you don't!

If neither of your chargers is three stage, you might consider disconnecting the batteries from the coach and buying a small solar panel trickle charger (about$50) and connect directly to your batteries. This is what we do with our tow vehicle and other vehicles that are only used seasonally, and it works very well.

[dznf0g]

I disconnect my converter and 100 solar keeps both batts full, even with 6-8 cloudy gray days in a row.

[alano]

Originally Posted by WestieHouse

Great information. After much study I plan to swotch out the stock converter on my 2015 FC 23FB. Does anyone have a recommendation for a particular 3-stage converter? What is approximate cost? Can someone who has average electrical (installing seitches snd fixtures in a house) knowledge do this?

Here a thread which explains how to upgrade your converter and suggestions on where to buy it.

The approximately cost is $200 and yes, if you have basic electrical skills you will be able to handle the upgrade.

[WestieHouse]

Thanks!

[Chuck Barber]

I was referred to Best Converter in Boise, Idaho by this forum. They were so helpful and suggested the correct converter for both of my AS trailers. They send the converter and great instructions immediately with credit card over the phone. I hate electrical problems and I am a rookie at this stuff but I replaced both old converters in about an hour with no problems. I highly recommend them. Best Converter.com

[Della]

Originally Posted by alano

rico, sounds like you have a couple of options in Winter if your connected to shore power for extended periods:

1. Best to not let your converter charge the batteries with a single-stage battery charger. So simply disconnect your battery. It's only necessary to disconnect one of the battery terminals and the preferred terminal to disconnect is the negative terminal (if you accidentally short out the negative terminal to the chassis there's no harm done). Some folks remove the negative terminal and wrap it in a latex glove for insulation.

2. Another option if you're connected to shore power for an extended period is to upgrade your converter to a three-stage battery charger. This way battery will not be overcharged.

3. Another option, would be to rewire your trailer as is done in the current AS models such that when the battery disconnect switch is in the Store position, the converter is connected to the main 12 V bus but the batteries are disconnected. In you case the portable solar system would connect directly to the batteries and happily charge the batteries during Winter.

Thanks sooo much. Helps immensely !!