I wanted a better 12 volts system in our trailer and I like cheap. So here is what I did. A more detailed view is posted on my blog at www.txmcook.blogspot.com
As I was rewiring our 16-Sc and adding 30 amp service and putting in a A/c, Hot Plate, Microwave, etc. I figured a updated 12 volt system would be nice. We have 12 volt lights in the form of LED's, halogen, etc in the trailer now under the bunks, cabinets, closet, etc. I used a old ATX Computer Power Supply from a computer to supply up to 18 amps of Clean 12 volt power to my lights, water pump and radio. What I mean by Clean is there is no static or interference.
I wired the supply into our 12 volt fuse block and it feeds all the systems. It works like a charm and only cost 10 bucks to make. Look at the pictures on my blog and let me know what you think.
Post by pathfinder3081 on Feb 13, 2013 15:04:20 GMT -5
I gotta checkout your blog for more detail.. but I like what I am thinking. The PO of my unit has left a real mess. I am thinking about channeling the wires different while I have her skin down as well..
Post by offspringin on Feb 13, 2013 16:36:50 GMT -5
wow that's a great idea, i have a bunch of these bad boys just sitting around. My old gaming tower got a brand new one shortly before i quit using it all together. I like this idea and will look into making this work for our trailer.
thanks so much
If you can't fix it with a hammer you have an electrical problem.
The only worry I would have is using that to charge a battery.
He's not using it to charge a battery. He is only using it to light the 12 vdc lighting. Although I really don't see the need. He says he was worried about plugging into a 15 amp service and when you do that, you just can't use more than 15 amps. Lowering your usage by powering LEDs with a powersupply is not really going to save you anything and it's not going to add to your AC power. I don't know what the power supply uses to convert to 12vdc and then power the LEDs. I know LEDs use very little power. But my main question is what's the point if you can't charge a battery for dry camping.
Newer trailers have almost all 12vdc lighting in them now. And many of the other appliances like your furnace, radio and maybe even the TV run on 12vdc. But they also have a 110vac system for wall outlets and larger stuff like refrigerator and AC. Then when dry camping your lighting is all 12vdc and you must run a generator for the higher powered AC stuff like the air conditioner.
I just don't see the point of having a 12vdc system powered by something that can not keep the battery charged for dry camping.
God grant me the strength to restore the trailers I can,
The courage to strip the parts from the trailers I can't,
And the wisdom to know the difference.
Me either, with no batteries why have a 12v system at all? You'd only use 1 amp with a couple of 60-watt light bulbs (a fraction of that if you used LEDs), leaving plenty for a small microwave. I guess the pump is the only thing that requires 12v if you're not not boondocking, so I guess it would work for that.
Dunno how much the hot plate or AC use, but IMO if drawing one more amp for the lights is enough to trip the breaker, you're probably running too close to the edge already.
Edited to remove dumb math errors
Last Edit: Feb 16, 2013 7:24:32 GMT -5 by cowcharge
Post by schweetcruisers on Feb 14, 2013 12:57:52 GMT -5
I could see the point if you always had hook ups and didn't want to lug around a battery so you could use your pump, but other than that, I don't get it. I just used one to test my 12v systems, once I decide on which battery to use, it is gone!
Where I come from most plastic campers have converter/battery chargers with an auto switch built into the power distribution panels. The industry has been using this for quite a while now
This does 2 things provides a steady 14 volts or so to the d/c stuff when plugged in or on generator and has a battery charger on the side usually something small but suficiant that will eventually float out.
there is another method
High end conversions use INVERTER/chargers not converters/chargers.
BIG DIFFERENCE heres how
Difference is the inverter turns D/C to A/C when no a/c input is available and then charges on the side when you do plug in and makes the switch automaticly.
THIS IS WAY BETTEZR AND WHY
With an INVERTER/charger any time the camper has a/c power from campground or generator it is a battery charger.
If it does not have a/c power coming IN to it the charging auto switches to invert and you continue to be able to use most of your a/c powered stuff from your battery bank instead.
If you boondock a lot this is a feature that would be way more valuable to you than if you are mostly using campgrounds wiith power available. But if you would be getting out in the wilderness this is the ticket and a few solar panels too
A CONVERTER will not do this it is meirly turning house current to 12 volt.
I know from experiance a 3000w inverter carries a 30amp main on it so that means 2 things to me. First you could wire the entire trailer thru it even if your upgrading to 30 amp and second with a 3000 watt inverter you would have no problem with large intermitten draws like the microwave or coffee pot or blow dryer or curling iron and when your out in the middle of nowhere.
If pulling it the tow vehicle charges from the alternator if at a campsite and pluged in your charging your battery and if your in tim buck 2 the sun is giving the batteries juice.
If I ever get enought time and money the astrodome will be fashoned like this
Without batteries the computer power supply would be fine.
You'd need a big battery bank to supply 3000 watts. That's 25 amps AC if you max it out (not that you would, hopefully), which means 250 amps from the batteries (10:1 DC to AC amps, some say 12:1 depending on the efficiency of the inverter). That would kill my two golf cart batteries in less than half an hour, at a 50% discharge rate, the max recommended for long battery life. But a 1500-watt hair drier would still pull 125 amps off your batteries, which would make for a pretty short boondock if you're Rapunzel, or even Steve Carell... I could let my hair grow for a year and still not need a hair drier (I tried it about five years ago, but I looked like Nick Nolte's mug shot).
I'm on a wicked low budget, so I got a 1000-watt inverter on ebay for $69 (like this one: www.ebay.com/itm/xantrex-inverter-1000-Watt-/261170891976?pt=US_Power_Inverters_&hash=item3cceff8cc8), to go along with my PD 9245 converter ($126, also on Ebay, and it has 4-stage charging). It's big enough to run a small microwave or several big TVs, and could easily be wired into the 120v wiring with one switch to avoid extension cords or the risk of accidentally running the inverter and shore power at the same time. It runs my desktop computer just fine, as long as you let the computer boot up before turning on the monitor and the surround sound. I'm pretty sure I could run the chop saw on it if I was careful starting it. Putting an isolator switch in the truck to charge from is a great idea too (mine was $30 at NAPA, plus the wire, you need pretty heavy wire to run 12v that far without losing it all in the wire, #8 at least, and #6 would be better). It's not fuel efficient to charge from when you're parked, but it's good in an emergency, and great while towing. Solar panel will be here as soon as I sell my old van
Last Edit: Mar 4, 2013 22:28:09 GMT -5 by cowcharge
continuing with the topic Id respond to the size and capacity of the battery bank and size.
Having the opportunity to bench test 2000 to 3000 watt inverters after fixing them this is what I can pass on.
One of the steps of testing them is having it invert untill the emergency low battery voltage circuit kicks in and works as designed.
I am continually suprised and what things and for how long they will run on 2 standard marine wet cell deep cycle batts thats all i use for testing.
2 batts are more than sufficiant to power a larger inverter with big INTERMITTIN draws like microwave and things with heating elements. NO PROBLEMO.
SOme of the crazy things I power of of a admittadly rediculessly small battery bank to speed the voltage drop and cut out test
A constant draw like a 5000 btu window air conditioner ran that for 1/2 hr before low voltage.
Plugged in the fridge in my home and it ran for 4 hr 3000w inverter 2 batts.
You do not need a bunch of batteries or solar cells to develop a adiquate system for boondock camping like I want
If your boondocking (and sunny) what that could get you in terms of battery voltage would be sufficiant enough energy to power LARGE INTERMITTEN loads during the morning coffee toaster bathroom stuff. EASY, easy this type draws on 2 batteries. After you use whatever it is you turn the inverter off instead of idling it. Plenty of capacity off of 2 batteries to do this.
During the course of the day they come back more than enough to give you tv time in the evenings but same thing after tv time turn the inverter off
This is what I would be expecting out of an inverter type setup and I believe it mirrors many other peoples camping habbits.
You have to manage your loads for sure. The most efficiant system would be the inverter is just bigger than what your needing and a smaller inverter draws less but they will not allow you to wire the entire camper thru them complicating things in other ways that for the way ill be camping am unwilling to compramise on.
I have also ran my tv dish box and satt dish for over 4 hr before getting down to lower than nessessary voltages.
sorry bout the spelling
Last Edit: Mar 5, 2013 12:35:10 GMT -5 by joecamper