Community Forums

Solo_RV_Guy · 08-23-2018, 10:02 AM

Quote:

Originally Posted by joelshort

Good to know. Another question, I believe the refrigerator runs off propane or electric. If the Gen is not running and not connected to shore power, the refrigerator will stay cold off the propane and automatically switch to electric when available, correct?

Correct. All of the absorption type refrigerators I've seen can operate on 120V or propane (heats the ammonia).

You might want to watch a couple of youtube vids on how these work and what is likely to go wrong (not leveling your RV can mess up the cooling and in extreme cases, damage the reefer).

Loggenrock · 08-25-2018, 09:38 PM

If the chargers for the batteries don't pull that many watts, a small inverter that plugs in to the lighter plug could run the chargers while travelling during the day. I use a 140W inverter to charge my laptop - think it was a whopping $25 or so...

LarryinID · 08-28-2018, 10:15 PM

Get a couple inverters you can plug into the 12 v sockets while driving. Plug the chargers into them. That’s what I did for computers before generator.

joelshort · 08-28-2018, 10:25 PM

The manufacturer of the LiFePO4 battery is building a 14.6v 25A charger for me. One advantage of the LiFePO4 batteries is they can be charged quicker at a higher current than lead acid or AGM batts.

Now that I know what charger I'll be using, I can get a large enough inverter for charging from the 12v sockets in the cab or coach while driving. The charger will probably pull about 400 watts (14.6v x 25A = 365w + some for heat loss). So a 1000w inverter should do the trick.

Should I have any concern about putting this kind of a load on the RV alternator?

joelshort · 08-28-2018, 11:01 PM

So it sounds like it's not safe to plug in an inverter that is higher than 200w into the cab or coach cigarette lighter 12v outlet. So if I have a 1000w inverter that will draw about 400w, what is the best way to hard wire that in to the RV 12v system? Would it be possible to tie into the electrical panel or into the house battery to run the inverter safely?

nothermark · 08-30-2018, 07:21 AM

I'd start with plugging it into the generator output in the morning. You can mostly charge LiFePO4 fairly quickly meaning currents that are high for a 12 V based charger but not much of a problem for 120 VAC based systems. If you give your batteries and hour or two in the morning then whatever charging is left will be low current lighter socket range.

joelshort · 08-30-2018, 07:28 AM

Quote:

Originally Posted by nothermark

I'd start with plugging it into the generator output in the morning. You can mostly charge LiFePO4 fairly quickly meaning currents that are high for a 12 V based charger but not much of a problem for 120 VAC based systems. If you give your batteries and hour or two in the morning then whatever charging is left will be low current lighter socket range.

That's a good strategy, although I'm trying to avoid using the generator if possible.

twinboat · 08-30-2018, 07:36 AM

Quote:

Originally Posted by joelshort

So it sounds like it's not safe to plug in an inverter that is higher than 200w into the cab or coach cigarette lighter 12v outlet. So if I have a 1000w inverter that will draw about 400w, what is the best way to hard wire that in to the RV 12v system? Would it be possible to tie into the electrical panel or into the house battery to run the inverter safely?

Tie it into the house battery with a fuse near the battery for safety. Keep the battery cables short and use an extension cord for the 120 volts.

Your alternator, while driving, will be able to cover a 35 amp draw.

nothermark · 08-31-2018, 06:00 AM

Quote:

Originally Posted by joelshort

That's a good strategy, although I'm trying to avoid using the generator if possible.

That limits the usability of the RV. You lose access to all 120 VAC devices while making breakfast and doing the morning cleanup routine plus using propane for water heating. That may encounter some pushback from the family. An hour or two of generator time in the morning and around dinner time supplies a lot of power when it is needed both topping off the batteries and avoiding sucking them down.

joelshort · 08-31-2018, 07:44 AM

Quote:

Originally Posted by nothermark

That limits the usability of the RV. You lose access to all 120 VAC devices while making breakfast and doing the morning cleanup routine plus using propane for water heating. That may encounter some pushback from the family. An hour or two of generator time in the morning and around dinner time supplies a lot of power when it is needed both topping off the batteries and avoiding sucking them down.

I wasn't clear. We will of course be using the generator as you suggest. My questions here really have to do with charging batteries while driving. I know I can run the generator while driving, but we are renting this RV and there is a fee per hour for generator use. I figure for the cost of running the generator I could instead buy a good inverter, charge the batteries while driving from the alternator, and keep the inverter for future use.