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rex_1_mn 10-31-2012 07:22 AM

All 12VDC for lighting
So I havent started on my conversion yet but thinking about all the decisions I have.

Is there any reason to have 120VAC lighting in the bus? It seems that pulling wire and wiring lights for DC and AC lights is a waste of time. Why not pull only DC and run them with LED's? I know you lose efficiancy going through the charger and such but with the small wattage LED's take that shouldnt be a problem.

What does everyone else do?

Thanks In Advance

bansil 10-31-2012 07:53 AM

Re: All 12VDC for lighting
I pulled 120 throughtout the bus so I would have recepticles everywhere anyways
I use 120v lamps so I can plug them in where ever light is needed.
At home I plug the bus in to 20 amp circuit(right now)
and can have lights, heat and run tools easily w/o extension cords everywhere

only 12v lights I use are the original lights with leds in them.

When I get battery bank up and running I will use 12v led lamps in a few places

Diesel Dan 10-31-2012 08:52 AM

Re: All 12VDC for lighting
I like Glenn's strategy of combining 12vDC with 110vAC lighting. If I had really wanted to "do it right" I would have done the same, but to keep things simple and get the job done quickly and cheaply as possible I ran all 110vAC wiring. I may still have the opportunity to retrofit some 12vDC stuff into the bus. I suspect that most of our camping will happen at places where we have at least 30 amps of AC power to draw upon, so I wasn't overly concerned with efficiency, but if it turns out that we do more boondocking than I expected, then I will likely add more 12v stuff. But so far we have not had any problems running off house battery power (through an inverter) during the day when we are travelling and then using shore power in the evenings when camping to provide power and recharge batteries. If I were to run a predominantly 12v system I would certainly buy a power converter so I could run my 12v directly from shore power when I have the opportunity. No point cycling your batteries if you don't have to.

gbstewart 10-31-2012 09:07 AM

Re: All 12VDC for lighting
all my lights are 12 volt, i have a converter, with 3 stage battery charger, keeps house battery charge when pluged to shore, or on board genny, all 12v stuff and 120v comes out of it as well, IMHO, a converter is the way to go for your electric needs.

just my 2 cents

PossumLiving 10-31-2012 10:58 AM

Re: All 12VDC for lighting
I don't even have a converter in my bus. What I do have is my old Trace inverter with built-in 3 stage charger that switches in automatically anytime the shore power input is hot. If the batteries are fully charged, it goes into float charge.
With this setup, I don't like to draw a lot of current from the batteries while on shore/generator power for fear of confusing the charger. A few LED lights or a couple of incans are fine.
When I am not on shore/generator power, I have two modes: full 110 volt lighting with the inverter powered on, and low-current mode with just a couple of LED lights directly off the battery.
One of the advantages of 110 lighting is that the inverter will protect the batteries by shutting off if the voltage drops below a set level; while DC lights will continue drawing current until the battery voltage reaches zero. But it is nice to read by DC light sometimes late at night, in the dead silence you only get when the inverter is off.

opus 10-31-2012 01:41 PM

Re: All 12VDC for lighting
I have 110v outlets on one wall. I also have an Iota power supply. Everything on the bus is 12v. When we park overnight we plug the 110v in and we are able to run everything 12v on the bus. This is how we run our Webasto too. I have a master power switch which I throw to keep it from using any battery at all.

Multitasking, home that made sense.

rex_1_mn 10-31-2012 01:46 PM

Re: All 12VDC for lighting
I will be wiring for 120VAC throughout for plug ins and such. For general room lighting and built In fixtures I am thinking all 12vdc its something you can use while boondocking as well as when you are hooked to shore power.

Any huge downside to this or something I am missing?

Which converters are you using?


opus 10-31-2012 01:57 PM

Re: All 12VDC for lighting
This is what I have:

I love it!

gbstewart 10-31-2012 03:00 PM

Re: All 12VDC for lighting
I started with a wfco 4500, it comes complete with the spots for your 120v breakers, and the 12v flat fuse, complete panel like you see in campers. then the converter part packed up, I think it was cause there was a voltage spike, then i got another converter and a hardwired a surge protector, then a year later the converter packed up once more, I got on the phone again and talked to the guy at best buy converters(that where i been getting this stuff from) hes that yes the wfco converters are not the good and suggested i up grade to a progressive dynmaics with the 3 stage battery charger. so far so good you can tell its better build the the last 2 i had, it fits right into the wfco fuse panel

all good

browncrown 10-31-2012 04:49 PM

Re: All 12VDC for lighting
I have all 12 volt lighting in my conversion and like others, 110 outlets for plugging in lamps if needed. I have two 50 watt Solar Panels on the roof that recharge the battery bank for everything that runs on 12 volt. In the process of coverting the bulbs to the new LED style.

lornaschinske 10-31-2012 07:01 PM

Re: All 12VDC for lighting
We are a fulltiming couple who tend to stay long term in RV parks. Our bus is 30 amp. We stay in parking lots when we travel (2-3 nights wallydocking/1 night in W/E hookup campground). We need to have a generator (looks like it will be LP) to power the homestyle freezer, refrigerator, 120VAC water heater. We set up our bus electric to reflect how we think we will use our bus. It works for us.

120VAC/8WATT single tube fluorescent lights powered by a little 750watt inverter. The inverter also powers the AC requirements of my LP range (electronic display & burner ignitors) and 120VAC range vent fan. I found that the 120VAC lights plus inverter were roughly 1/2 the cost of installing the same number of 12VDC Thin Lites. We have a Progressive Dynamics 3 stage battery charger for the house bank ( had the best price + shipping). I need to buy 3 Deep Cycle 12Volt Marine/RV house batteries. Only 12VDC stuff we have is the water pump, fans on the hydronic heat exchanger, the CB and automotive AM/FM/CD player (possibly one other thing I have forgotten). I haven't decided for sure if we will power the TV/DVD player off an inverter or not. Probably will. Individual dedicated inverters are pretty cheap.

Since we stay in one place long term, I want to be able to have lights, cook and watch TV if the power goes out... like it did in Albuquerque for over a week due to a winter storm. So far we have only experienced power outages of less than 1 day. We also have electric heaters (electric is included in our site rental), LP space heater and the "whole house" hydronic system is set up for AC/LP. We need to be a little flexible in our power sources.

BTW, LP generator (7KW?) because we rarely need to use a generator. An LP generator will sit for years then crank right up without any problems. Since we use LP anyway (three 20# BBQ tanks on a manifold plus one 20# BBQ tank on an auto change over as a back up) it will be a simple matter to run a gas line back a little farther to hook up a generator. Much less hassle than trying to find a space for the fuel tank gas or diesel generators require.

ol trunt 10-31-2012 09:54 PM

Re: All 12VDC for lighting
Lorna, I rolled over on the lp genny and had a small gas tank fabricated for the genny--mostly because I could find a nook to put it in and no more room for a larger lp tank. I agree that lp makes better sense but oh well. I don't think I'll be able to use all of the output my 3KW genny produces so a 7KW sounds like way over the top to me. Just my two cents worth.

rex_1_mn 11-01-2012 08:36 AM

Re: All 12VDC for lighting
So when using an all in one converter/charger/power distrubution center if its not pluged in to 120vac you can still pull 12vdc through the panel fused circuits from the house batteries right?

Also how about your inverter? Is there a spot to tie this in to the converter/distrubution center? I assume it self explanatory when you get the distribution center but never done this before and want to know what I am getting before I buy.

Thanks In Advance

Diesel Dan 11-01-2012 10:54 AM

Re: All 12VDC for lighting

Originally Posted by ol trunt
I don't think I'll be able to use all of the output my 3KW genny produces so a 7KW sounds like way over the top to me.

I have a cheap Champion brand 3.5KW generator that is like new, and when my 15,000BTU air conditioner cycles, it sometimes kills the generator. I tried installing a hard start capacitor on the AC to no avail. It's a bummer. :(

roach711 11-01-2012 11:07 AM

Re: All 12VDC for lighting

Originally Posted by rex_1_mn
So when using an all in one converter/charger/power distrubution center if its not pluged in to 120vac you can still pull 12vdc through the panel fused circuits from the house batteries right?

Correct. When you're plugged into shore power the charger tops off the batteries and the converter converts 120v AC to 12v DC to power whatever 12 volt stuff you have turned on. Just make sure your all-in-one panel has enough amp capacity to handle both loads. When unplugged you're running strictly from the batteries.

An inverter takes 12v DC power from the batteries and makes 120v AC power. The inverter connects directly to the battery bank (fused) and should be wired with as short a cable as possible to keep cable voltage drop as small as possible. Mount your inverter outside the battery enclosure to avoid corrosion from the battery fumes.

Both AC to DC CONverters and DC to AC INverters lose about 15% in the conversion process. This isn't a big deal for the converter, since you're plugged into the power grid or a generator, but inverters will tend to suck your battery bank dry in a hurry.

To avoid that 15% inverter "tax" I set up our bus to run almost exclusively on 12v to get the most out of our two 6v golf cart batteries. I did install two 120v AC plugs for use when we're on shore power. We use a small inverter that plugs into the cigarette lighter socket for charging phones and computers but mostly use it when we're driving to avoid draining the starting batteries.

We're weekend warriors and don't mind leaving the hair dryer and microwave at home so our power needs are minimal and the battery bank is sized to match, but if we were full-timing I would want a much different setup (and a much longer bus). :)

lornaschinske 11-01-2012 02:45 PM

Re: All 12VDC for lighting

Originally Posted by ol trunt
... I don't think I'll be able to use all of the output my 3KW genny produces so a 7KW sounds like way over the top to me. Just my two cents worth.

12 cf AC electric freezer, 8 cf total AC electric refrigerator, 20 gallon AC electric water heater. I also want to be able to dry my hair with the electric hair dryer, wash clothes (LP dryer), watch satellite TV/movies and basically experience no loss of comfort during a power outage since I doubt the excuse of "we have no power" would fly as a reason to not go to work. Of course that point will be moot once we win the lottery (gotta buy a ticket first :lol: ). We want to be able to power EVERYTHING and still hold the generator at 50% for most economical fuel usage. I would rather have too much generator than not enough.

rex_1_mn 11-02-2012 01:30 PM

Re: All 12VDC for lighting
So because the charger/converters I am looking at is also going to be my distribution panel it makes sense to wire the inverter to the AC input side and only turn it on when I need it. Will it work to wire the inverter as well as the shore power connection to the input AC side? I suppose I will need to use a selector switch to isolate thenm so when one is on the other is no connected.

ol trunt 11-02-2012 08:59 PM

Re: All 12VDC for lighting
You will need a switch. Remember also that when you use shore power you must use shore ground and when you use the inverter you must use inverter ground. Shore and inverter must never be mixed together--it will let the magic smoke out of the electrical system and if done just right, you too.

toasterman12 03-02-2016 05:57 PM

DoEs the converter /charger plug into the battery only, or are there 12 volt leads also, I have a converter from 1978 that doesn't charge batteries but has 4 12 volt leads ,

Jolly Roger 03-02-2016 06:59 PM

I am going with the KISS method
I do know electricity( commercialy ) SHOW IT RESPECT.
Mine will be ran seperate with no converters or inverters or whatever switches?
I do plan on full time eventually
If I have a problem with my 12v system I won't have to worry about anything but it
Which is completely seperate from my bus batteries that way I know if the bus don't start then it is in that wiring and not a switch,converter,inverteror other drain from somewhere else.
For now
For my 120 I have a 10 guage extension cord 100' long that can be used short as shore power or can be stretched out to get the generator noise away from the bus and I have a 50$ Schumaker charger/maintainer in my house battery compartment to take care of the 12v including of course a seperate extension cord that can reach the same generator.
Through my construction experience
You always earth ground a generator/welder and with my set up when I have a problem with a specific system? I know exactly where to go and if I have set so long that my bus batteries ain't enough then I already have a battery charger on board ready do what I need.
No convert/invert/switch?
Money/time/later on problems? Forget it. At worst I have to work on a sears/Roebuck genny that I have had forever and already had to so no biggie.
Electric wise
If you get fancy then you need to earth ground everything including the 12v because you can/chance get high voltage back feed through your convert/invert when it mucks up?
OK all you sparkles in our world here please correct me if I have made bad choices?

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