When running on battery / solar only, questions...

Jay_and_Kat

Just planning ahead here for a possible boondock(ish, the campground won't have 30/50amp hookups) camping trip.  We want to ensure we don't run into problems and just want to clarify / verify / find out a few things.  Our camper is a 2022 T@B 400 Boondock, stock batteries and solar (so lead / acid I believe and one solar panel)

1. Would we be correct in presuming we can leave the water pump on, and it will only draw power when it brings the pressure back up in the lines, such as from flushing the toilet?  Or should it be turned off when not using water?  (leave aside the possibility of a blown line / fitting)
2. Are we correct in presuming that the inverter DOES have a constant draw when on, and thus, to leave it off except when we need a working outlet?
3. The lights are not a significant draw on the batteries

And the batteries getting recharged / how quickly they charge depends entirely on how much sun the solar panel gets.

Upgrading the batteries and adding backpack solar is currently not in out plans / budget.

swiftwave

The water pump only draws power when it is actually pumping.  I still prefer to turn it off overnight and when I leave the trailer.
Yes, the inverter draws power just by being on.
The different lights in my 2020 T@B 400 draw significantly different amounts of power, as evidenced by monitoring via a smart shunt.  In my trailer, the light strips draw the most power.

bergger

Yes I agree with what @swiftwave has said.  We also turn on the water pump when needed and usually turn it off when done.  If you leave it on it's not really an issue on the power draw.  Definitely do not keep the inverter on when not needed.  And yes, as our smart shunt shows, the accent lights use significantly more power than the other lights, ie the ceiling lights, reading lights and kitchen lights.  We have a 2021 still with our original AGM batteries and boondock often.  We've never come close to running the batteries down.  And this is with us using the inverter every morning to run our coffee pot.  You should be fine as long as you are mindful of your electrical use and have sun to take advantage of the solar.  I recommend installing a smart shunt.  Well worth the money as you can see the power draw of everything in the trailer.  

pthomas745

The inverter (the PRX1200 is what I think you have in your trailer) draws 1.2 amps.  Every hour.  There was a spreadsheet for a 400 from a few years ago that covered the differences in the lighting amps used.  (There are probably more if I dig around).  As you can see, some of the lights are not even worth counting.  Look over the sheet carefully, because this owner split things between summer and winter, and apparently they had tank heaters, etc.  The fridge power use may be different also, since this sheet is based on the Norcold 751BB.  The listing for the fridge says it only gets used for "4 hours", but what that really seems to mean is as the fridge cycles on and off during the day, the "total" run time is only 4 hours.

The spreadsheet comes from this "Unofficial Tab 400 Manual" which is filled with good basic information.  Based on a 2019 400, so your mileage may vary, but still quite useful.

Grumpy_G

If you need to run on batteries you might want to check their condition/test them before heading out. If you exclusively camped with hookups in the past you wouldn't know if there's a problem.

manyman297

Best practice is to turn the pump off at least when not present at your campsite. Not because of energy draw (which there are none) but more for safety. Imagine the nightmare of a fitting leaking or a catastrophic failure somewhere in the plumbing and the pump continues to pump your water tank dry.

Marceline

If you have a compressor (2way) fridge, that’s going to be your biggest draw. It can help to put drinks in a separate ice chest and open the fridge as infrequently and as quickly as possible. If you have a propane fridge you’ll probably have no issues. 

Jay_and_Kat

@Marceline we've got the older 3-way fridge and my thinking was along the same lines as what you're saying.  Keep drinks that DON'T require refrigeration (sodas, water, gatorade) in a cooler with some ice packs, things like milk in the fridge.

Then minimize opening the fridge as much as possible.  That despite the fridge would be running on propane.  Probably also keep a couple of the ice packs in the freezer to cool them down to swap out the ones in the cooler.

ScottG

With a 3-way fridge running on propane and judicious power use, this is very doable. I've been out as long as nine days with just a single large lead-acid battery and 100W portable panel. I like the portable as I can get it in the sun even if the camper is shaded, but if you have an open site and sunny skies at least part of the time, your rooftop panel should serve you just as well.

It sounds like you won't have hookups, but will still be in an established campground. If you can use campground showers and toilets, you'll save both power and tank capacity. The latter is probably the bigger concern, though it may be less of an issue with the 400's larger tanks.

Jay_and_Kat

@ScottG you are correct, this would be at an established campground and the area we'd be setting up in isn't very far from the showers / bathrooms.  We've not yet camped with more than electric hookup so other than middle of the night needs, we're used to using campground facilities as much as possible.

So, comparatively speaking, this might not be that big of a change for us.

ScottG

I think you'll be fine, you'll just need to be a little more attentive to your power usage and state of charge than you might otherwise be when on shore power. Be aware that running a typical lead acid/AGM battery to the point where it "dies" will cause permanent damage to the battery, so try to avoid getting to that point.

Also, I'll reiterate @Grumpy_G's suggestion to check your battery out carefully before your trip. It's easy enough to get to a campsite and find out the battery you've happily ignored for two years is no longer working! 

morey000

If you want to invest in something, getting a 100Ahr Lithium battery will give you 100Ahr of usable power, vs the stock lead acid, which is a 75Ahr (?), only half of which is usable.  I've done a lot of research.  these are really good:  https://www.litime.com/products/12v-100ah-mini-lifepo4-battery

manyman297

Just got back from a two night trip using our new 200ah of LiTime batteries. It definitely feels worth the price. We ran the interior fridge (small one under the stove on our 2021 400) and a 25qt 12v cooler sitting in my truck bed. Temps weren’t extreme though @ 75 degrees but both fridges got a workout. Partially sunny days. By the end we were at 70% capacity which isn’t bad considering both refrigerators combined are pulling 90-100 watts when running together. 

I don’t have much to compare it to other than our old AGMs which I know would’ve been run down to 50% at least.

What I didn’t consider is how much solar it takes to get back to 100%. With the stock 160w panel it struggles to recharge. If we do longer boondocking trips we’ll definitely look at getting a solar suitcase to supplement.