Reply
 
Thread Tools Display Modes
 
Old 03-21-2012, 02:57 PM   #1
Senior Member
 
Viva's Avatar
 
Join Date: Feb 2012
Posts: 879
New house system: Go 12-volt without inverter/converter?

Hi folks,

I'm assuming that I will want a fresh start on any electrical/charging/"house" systems on a 1990's SMB, since things have come a long way since then for house/charging systems. So, I'm thinking over how to plan it out.

And this is not to pick on SMB, as most/all older camper/boat systems I've seen are fairly outdated, simply due to the march of time. Also, some of them seem overly complicated or inefficient due to the need to have everything work two or three ways, which I may not need.

In addition, I want to have systems that are fresh/tidy/totally understood by me.

For my uses I would like to favor a "boondocking" type system, with plugging in to "shorepower" being the less-usual scenario. So, probably solar panel, controller, decent battery bank, charge monitor. That would all be 12-volt. I tend to favor Blue Seas and other similar marine-type brands.

My question (yes, I am getting to it ) comes in the area of charger/inverter/converter land. Is there any sense (or lack thereof) in making my system all 12-volt, and then - instead of inverting/converting as a part of the charging system - just going for a 12-volt system wherein when I do plug in, I'm simply charging the batteries, and then running in 12-volt from those charged batteries just like I would when not plugged in? In other words, I'm always using the same system (12-volt) and when I am (infrequently) plugged in, I'm still using a 12-volt system, but just charging the batteries via 110 "shorepower."

I suppose this would cause more wear/cycles on the batteries, but on the other hand it keeps things simple, and my systems are same/similar whether or not I'm plugged in - that has some appeal. And too, maybe having to buy a couple of T-105's (or whatever batteries) a little sooner (due to more cycles) is still preferable to me than installing inverter/converter, etc.? I could perhaps spend some of the money I would have spent that way, on the 12-volt system (panels, etc.). So, go for one robust system instead of a 110 and a 12-volt system.

Note: I would probably still have a little portable "cigarette lighter" type inverter for occasional use, but my computer, phone, refrigerator, lights, etc. are all 12-volt chargeable/runnable. I don't have anything but very-occasional-use items that would need 110. No toaster, no air-conditioner (except for the usual dashboard one), no hair-dryer, etc.

The two larger draw items I can think of would be furnace fan and refrigerator. Not sure how those would play in. They are typically both 12-volt, but higher draw. I suppose I could see times I might have shorepower available and want to use a heater, so how would I handle that. Since I'm a light sleeper and hate heater fans kicking in and waking me up, maybe just a portable silent electric heater for those times? With a "direct" shorepower connection that feeds an outlet? I don't see that as being a frequent occurrence, and I'm not sure it's worth planning my system around that, if that is the one thing that makes it more complicated, or draws money away from planning a good 12-volt/solar system.

As you can see, I'm not totally sure what I'm doing here, so I would love to hear your thoughts on this - thank you!

Viva
__________________

Viva is offline   Reply With Quote
Old 03-21-2012, 03:48 PM   #2
Senior Member
 
bratworst's Avatar
 
Join Date: Aug 2011
Location: California
Posts: 111
Re: New house system: Go 12-volt without inverter/converter?

If all of the devices you have are 12 volt, I'd keep it simple and stay with that. I have the complete SMB 110 volt system built in, and I plug in once in a while when I stop at a Park that offers it, but even when I do plug in, I rarely ever use the 110 volt outlets. The main reason I have 110 is for my A/C when it's super hot!
__________________

bratworst is offline   Reply With Quote
Old 03-21-2012, 04:07 PM   #3
Site Team
 
Ford_6L_E350's Avatar
 
Join Date: May 2007
Location: Washington - Ridgefield
Posts: 4,725
Re: New house system: Go 12-volt without inverter/converter?

Actually, what you suggest is similar to my SMB.

No inverter. When I plug into shore power, it powers two AC outlets and a built-in battery charger and nothing else. I even unplugged the refrig so it only runs on DC.

I have a 130w solar panel and a Blue Sky 2000 controller. Unless I'm in full shade, I can dry camp for an unlimited time (well, not limited by battery/solar power).

A SurePower 1315 battery separator keeps all the batteries charged, either from solar or from driving.

It is a simple and effective setup.

Mike
__________________
SOLD04 EB350 Custom Floorplan
6.0 PSD 4.10 Posi
Salem Kroger coil spring 4wd
SMB Trailer w/AT Air Suspension
Alaska to Key West, Labrador and more
130685 miles 16.65 mpg average

Prostate cancer survivor. viewtopic.php?f=8&t=11099
2015 VW GTI
Leaving CA for WA
Ford_6L_E350 is offline   Reply With Quote
Old 03-21-2012, 05:44 PM   #4
Senior Member
 
rockbender's Avatar
 
Join Date: Sep 2010
Location: Bend, OR
Posts: 799
Re: New house system: Go 12-volt without inverter/converter?

My original intent was pretty much the same as yours and Mike's. I never planned on plugging in, so why bother with shore power at all? I thought it might be nice to have an inverter just because. I ended up getting an inverter/charger (older used unit, but still a workhorse) and am quite happy I did for the following reasons:

1. I park in the garage as often as I can, so the solar does no good to keep a trickle charge on the batteries.

2. there is always some parasitic draw on your system somewhere. It may be a few milliamps, but it all adds up over time. If you aren't using the rig for a while it's nice to be able to top off the batteries easily once in a while.

3. While charging off your alternator works in theory, a lot of the trips we like to take don't entail enough driving to catch up on a weekends worth of battery use. Plugging in to charge lets you ensure you have a fully charged system for the next trip.

4. If I do happen to have shore power available, then I can use power without regard... leave lights on, charge the laptop, crank up the fridge so it is pre-cooled for future travel, use the radio, etc.

So I really don't use the inverter portion much, if at all. However, I think I would definitely want an onboard charging system as Mike has described at a minimum.

That's my opinion. Before you get excited about spending money and swapping pieces and parts out, it would be good to identify what you already have. There may or may not be reason to change much of your system.
__________________
Josh
2009 Express AWD, CCV Top & 50-ish home build. Daily driver/camper/kid hauler
rockbender is offline   Reply With Quote
Old 03-21-2012, 05:52 PM   #5
Senior Member
 
Join Date: Apr 2011
Location: Oregon Ciry Oregon
Posts: 2,518
New house system: Go 12-volt without inverter/converter?

I have a similar setup to Mike's except no solar. Everything is 12v plus a couple of 120v outlets that I only use at home in the winter. I plug an electric heater into it to keep the chill out of the van.


Larrie
89 Ford 2WD penthouse
__________________
Larrie
Read detailed trip reports, see photos and videos on my travel blog, luinil.com.
Visit my Patreon page: patreon.com/LarrieEasterly
Current van: 2002 Ford E350 extended body camper with Colorado Camper Van pop top and Agile Offroad 4WD conversion.
larrie is offline   Reply With Quote
Old 03-21-2012, 06:15 PM   #6
Senior Member
 
Viva's Avatar
 
Join Date: Feb 2012
Posts: 879
Re: New house system: Go 12-volt without inverter/converter?

Thanks all for the input so far

Mike and Larrie: Great to hear about your systems, as they sounds like what I was imagining, plus make it possible to use shorepower directly through a couple of outlets (for heater, say) the occasional time when it is available. It's really nice to hear your real-world experience of a similar system.

******
Extra rambling:

Just to clarify, I was thinking I would have a charger, but simply that it would "only" charge my house batteries, and then I would be getting my power mostly through the batteries vs. through a separate 110 system or inverter (except for those couple of outlets powered directly when plugged in).

I'm used to boats. I didn't design the systems on them, but basically they were set up how I was thinking. i.e. there was a "shorepower" inlet, but it simply allowed charging the house batteries via a charger (shorepower connections were rather few and far between anyway) and then 12-volt items were used just the same as when away from shore (batteries normally charged via solar panel and wind generator, or engine alternator, with the last being least desirable).

I suppose all I'm thinking of leaving out is an inverter or converter and whatever wiring or switching goes along with it. And it's not that I'm "cheap," but more that I would like to eliminate overlapping complexity (when feasible) and focus any money I do spend on the systems I would use most.

However, one thing I'm not sure about is how much more money/wiring/complexity the inverter or converter add. I'm thinking it's something I want to avoid, but maybe I'm making too much of it? I just find that the more complexity, and the more everything is designed to work two or three ways (especially in a small space), then usually the more expense, clutter, space, weight, and difficulty pinning down the inevitable problem or failure. That's my motivation more than money.

I'll keep reading the thread - thanks!

Viva

PS: Larrie - I like your old-school SMB. That body style always looks so "clean" to me (and yours is such a well-preserved example). (Yours too, Rockbender!)
Viva is offline   Reply With Quote
Old 03-21-2012, 06:51 PM   #7
Senior Member
 
dhally's Avatar
 
Join Date: Sep 2009
Location: SE Washington
Posts: 841
Garage
Re: New house system: Go 12-volt without inverter/converter?

I would agree - why change out the existing equipment if it works? The increased "efficiency" would be lost in the rounding error.

Once the 120v is installed into the van, adding a 120v receptacle is fairly cheap. We only use ours at home or when we stay in an RV park.
__________________
---------------------
2009 E250 RB 5.4L "SilVan"
dhally is offline   Reply With Quote
Old 03-21-2012, 07:15 PM   #8
Senior Member
 
Viva's Avatar
 
Join Date: Feb 2012
Posts: 879
Re: New house system: Go 12-volt without inverter/converter?

Quote:
Originally Posted by dhally
I would agree - why change out the existing equipment if it works? The increased "efficiency" would be lost in the rounding error.
I hear you, as it's often un-wise to just jump in and start changing things before trying them out. I'm probably somewhat pre-judging, but it's not completely without empirical evidence. So far none of the older RV's, vans, or boats I've looked at (in my "older" budget range) have ever had up-to-date charging systems. Seems like 99% of the time they have whatever was put in originally in the 1990's, which is pretty clunky compared to what we can install nowadays. Solar panels, battery monitors, and charge controllers have all come a long way since then. Even just a battery monitor can improve things by giving you precise information about the house bank, so you know where you stand.

I also have noticed that "factory" systems often seemed to be optimized for driving or being plugged in, neither of which would be my primary scenario. That's not to say I don't want to grab every alternator amp I can get when I'm driving, but I don't want to have to go for a drive just to charge, either, if I'm in a nice spot. (And from what I can tell, even the charging-while-driving is a bit "un-maximized" by most 1990's setups.)

Again, this isn't to dis the 1990's, or SMB, but things have come a long way since then. I haven't yet found a "budget" SMB that had an up-to-date, maximized for my uses, charging system (understandably, as they aren't cheap, and if one is going to be plugged in most of the time, probably not necessary either). Maybe too, the type of person who sets things up optimally is less likely to be selling, especially in the under-$10k price range.

So, I've been thinking about charging systems and how I would want the overall picture set up. It's still a bit wintery, so a good time to plan and scheme I admit to having a strong aversion to bunches of wiring and components that I have not installed myself, because I like to know what I have, and know that it's done to my satisfaction (proper connections, large enough wire, short wire runs where they are possible, etc.). Of course if I find an SMB in my range with a nifty solar/controller/monitor/inverter setup, I won't likely be tearing it out!

I tend to favor boondocking or the less developed Forest Service type campgrounds, so no hookups there. I can see possibly stopping at a friend's for a visit and plugging in, but probably not my typical mode. When at home, I was thinking a cut-off switch to eliminate any parasitic house loads, and not leaving anything in the refrigerator but instead cleaning things out and basically shutting down the van. (Refrigerator is a new one on me, as I'm used to iceboxes. So maybe I'm off base on this.)


Quote:
Originally Posted by dhally
Once the 120v is installed into the van, adding a 120v receptacle is fairly cheap. We only use ours at home or when we stay in an RV park.
I'm not against having a couple of 110 volt outlets at all. I was just considering skipping the inverter/converter bits that either turn 110 into 12-volt or 12-volt into 110 within the van.
Viva is offline   Reply With Quote
Old 03-21-2012, 09:09 PM   #9
Senior Member
 
Join Date: Apr 2011
Location: Oregon Ciry Oregon
Posts: 2,518
New house system: Go 12-volt without inverter/converter?

Viva

Thanks for the compliment on my van. We like it a lot.

An alternate solution might be to go with the 12v system with 120v charger like you are considering. Then sometime in the future when you need it and can afford it you could purchase a portable inverter like http://m.sears.com/productdetails.do?pa ... 871496000P.


Larrie
89 Ford 2WD penthouse
__________________
Larrie
Read detailed trip reports, see photos and videos on my travel blog, luinil.com.
Visit my Patreon page: patreon.com/LarrieEasterly
Current van: 2002 Ford E350 extended body camper with Colorado Camper Van pop top and Agile Offroad 4WD conversion.
larrie is offline   Reply With Quote
Old 03-21-2012, 09:54 PM   #10
Senior Member
 
Viva's Avatar
 
Join Date: Feb 2012
Posts: 879
Re: New house system: Go 12-volt without inverter/converter?

That does sound like a good option, and I already have one from boat days, so.... bonus! I used to use it for a few quick, semi-infrequent tasks that required certain appliances or tools where it was just easier not to get a 12-volt version or adapter.

I do have my commonly used items in either 12-volt (or 12-volt adapter) or AA/AAA batteries (with a 12-volt charger for rechargeable batteries).
__________________

Viva is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Powered by vBadvanced CMPS v3.2.3
Disclaimer:

This website is not affiliated with or endorsed by Sportsmobile SIP or any of its affiliates. This is an independent, unofficial site.


All times are GMT -6. The time now is 05:31 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
×