Post by Gone Kayaking on May 7, 2011 10:25:20 GMT -5
Okay, got my friend who has done off grid electrical to come over and eyeball my set up and walk me through. I thought I had the record button on my iphone set but realized after he'd finished talking that I hadn't (oops) so I went inside and immediately did a brain dump...and this is what I came up with.
My goal is to be able to boondock for several days at a time while traveling, to save on campground fees (to use for gas) and to get away from it all.
Since most of what's in already is 110 and my gear (laptop, ipad, toaster oven (to be used sparingly) is too, I'm planning on an inverter rather than going strictly 12V. The fantastic fan and the light above the bed which are both 12V will be wired directly to the battery. Here's my plan and below that a wiring diagram. Comments please. The set up will live under the dinette benches.
What I will need new style Breaker fuses (15 amp) Deepcycle marine battery (2 350 AH mount above frame on each side of dinette, wire as inline) Trickle Charger and Solar panel to connect to it Inverter, pure sine (700 amp hour) (Samlex PST- 150S -12A 1500 Watt DC/AC Pure Sine Wave Inverter)- 12V What to do Wire for outlets, lights etc… as per normal One pigtail that goes to the house current One pigtail that goes to inverter Inverter goes to battery 12v fan and 12v light wired to battery, potential also run to car battery to get charging while driving (?) If using duplex outlet tape over it to prevent 12v and AC being plugged in at same time (upgrade to a switch later)
This looks interesting and I want to know more from those who know what they are doing regarding this, because it is very similar to my idea (although I read in a few places that batteries need to be vented to the outside to prevent the buildup of hydrogen gas.... this is what has me freaked out and thinking i need to have my battery outside). Anyone have thoughts on the safety of doing the battery inside like this??
I'm not sure on the batteries; I would make absolutely, triple SURE they will never gas...All of my batteries are on the tongue.
First thing: you will need a battery maintainer rather than a trickle charger. They will not overcharge (ruin) your batteries. Buy one designed to maintain more than one battery. It will state right on the package "won't overcharge" or something similar.
Use a 12 volt fuse block (rather than directly to the batteries) for your Fan and light and add a cigar plug. They are unbelievably handy and can even be used to charge your batteries. (very easy to install thru the dinette box) Fuse blocks are available at most auto parts stores, Auto Zone sells them for 10 bucks.
The inverter will draw your batteries down quickly if used for anything more than small things: laptop, radio, etc. The toaster oven will suck them dry.
You will need a 7 way plug and charge line for sure to top off the batteries while driving. Another item that I would have is one of those portable batteries. They can give power in a pinch; some have lights, compressors and a built in inverter.
I really think you need a switch to change from inverter to shore power. Taking a chance of having both plugged in at the same time could cause some troubles...
Post by Atomic Addiction on May 8, 2011 3:04:39 GMT -5
I have seen trailers modified to use a baggage area to house batteries. The baggage area is sealed off from the rest of the interior by a fabricated metal box. The baggage door or skin very close by has to have some kind of vent installed.
I think the baggage door areas are commonly used because it allows easy access to the battery compartment for service.
It isn't impossible to safely house batteries inside a trailer but you have to create special places for them. They arnt something you can just place at the bottom of your closet.
Those sealed agm batteries are about as safe as it gets. Even if you have a breakdown in the charging system and you over charge them for days they don't break the seal. I plan on putting a couple under the seat up front with a battery tender, tied into the 12 volt system and I wasn't going to vent them. I use them for all of my kids battery ride on toys too because they can take the vibration, don't leak and don't gas.
"AGM batteries are not the best choice for all applications - they are rather expensive compared to flooded batteries. However, their safety and design features make them the battery of choice for many applications, such as:
* Where you cannot have fumes or hydrogen, such as in poorly ventilated areas, or where fumes may cause corrosion to electronics, such as repeater and cell phone sites. * Where resistance to shock and vibration is important. * Where spilled acid from leaking, tipped, or broken batteries cannot be tolerated. * When installed in a location where maintenance would be difficult or expensive, such as remote communications sites. * Where the batteries may be subject to freezing (-40 degrees F or lower). * Anyplace where you need a reliable totally sealed battery for safety or environmental reasons - wheelchairs, medical standby power, inside RV's, computer room UPS systems, or in enclosed spaces in boats."
Post by Gone Kayaking on May 8, 2011 10:53:37 GMT -5
Thanks on the fuse block, forgot about that and I'm bagging the toaster oven (what's the propane for anyway? duh). Which brings my Amp Hour load down to 200 for a three day boondock.
Came across these great discussions/tutorials, which all seem to support the idea that I could put them in the dinette box and one argues against putting them on the tongue. www.marxrv.com/12volt/12volt.htm
Thanks Jeremy for those helpful tips on the AGM battery... that helps me feel much better. So maybe I can keep the battery inside in a storage area behind the wheel well like originally intended (under the bed)... with a hinged lid (like Gremlinguy did on his Compact) for access... and just to be extra safe, install a little round vent to the outside.... does that sounds like it would work?
ACTUALLY the more I think about it the more I think I just need a battery and a converter... and just have 2 separate systems with side by side plugs, one for when I have shore power and one for using battery power. So everywhere I install a standard plug I also install a 12v plug... the 12v will always be available, whether or not we have shore power, and when we have shore power we can also use the standard plugs AND it will charge the AGM battery....
Post by Gone Kayaking on May 8, 2011 19:16:01 GMT -5
Hi Jeremy You must have been posting while I was composing my last reply. I also saw that post. I've also decided in the interim to add 12v fixtures (except for the already 110 lamp that's original) a couple of 12v outlets for 12v appliances I might acquire, and then a couple 110 outlets to run with the inverter, or shore power when available. Of course that will also mean adding a converter to the mix. But I don't think I'll need the 700AH of battery that I thought I did using mostly the inverter. This way I'll be going the other direction.
1956 Shasta 1500
Can't wait to go campin'
Good choice on the specs. seemsto be working all right from the pictures. When i go boondocking or in the ruff I have a 1250 watts genorator that I use since the whole camper is wired for ac no dc in it. A full tank of gas in it operates for 4 hours and but make sure it is a 2 cycle generator,I fab a coffee can w/ a extended pipe off of the muffler of the generator--filled the coffee can with water and put the muffler pipe from the generator in the water and ever so quite running it. But make sure your generator is a 2 cycle so you don't get any back pressure from it Works fine No added expence except 99.00 from harbor frieght. Even use it in camp grounds where they say no generators to be use, I put it in my bed of the truck with a wooden box over it entirely to cover the whole thing and run the ac cord from there.the sound u get from it is like a child blowing bubbles in a bathtub.