12v jump pack to provide dc power and ac to dc converter

[Tomb1269]

Hello new member as I am starting my build but I have been lurking for several years and learning. On to my question, has any one used a 12v jump starter pack. The portable car start packs with a small air compressor and a dc power port that can be used to power dc stuff as well as charge the packs battery and it already has a ac to dc charge cord. I am building my trailer to serve a dual purpose. 1st as a gear trailer for my boy scout troop and then second to be a basic camper trailer. so therefore i would like to have lights (roof vent fans that run on 12v) that i can run on battery and on ac whether connected to the trucks electrical or stand alone. in addition, i do not really have the ability to shorepower a standard battery charger for a standard rv battery as i live in a townhouse complex and park the trailer in over flow park. so the idea is that i could take the pack ouy and charge it at the house when not camping or scouting. i know how to set up the wiring just not sure it anyone else had tried this.

thanks
tom
ps sorry about the lower case lettering for some reason some sights do not like to let me use the shift key very well.

[eamarquardt]

Hello new member as I am starting my build but I have been lurking for several years and learning. On to my question, has any one used a 12v jump starter pack. The portable car start packs with a small air compressor and a dc power port that can be used to power dc stuff as well as charge the packs battery and it already has a ac to dc charge cord. From what I've heard about these devices the battery is too small to do much of anything. If Tumbleweed Tex had aske this question I'd say: "DON"T BUY ONE YOU'LL BE DISAPPOINTED". The stories I've heard about these units is in alignment with my experience with battery power. Bigger is better. I am building my trailer to serve a dual purpose. 1st as a gear trailer for my boy scout troop and then second to be a basic camper trailer. so therefore i would like to have lights (roof vent fans that run on 12v) that i can run on battery and on ac whether connected to the trucks electrical or stand alone. in addition, i do not really have the ability to shorepower a standard battery charger for a standard rv battery as i live in a townhouse complex and park the trailer in over flow park. so the idea is that i could take the pack ouy and charge it at the house when not camping or scouting. i know how to set up the wiring just not sure it anyone else had tried this.

Your options are:

1) Charge your battery from your tow vehicle while driving.

2) Use a charger keep your battery charged using shore power. Something like this would work well: http://www.batterystuff.com/battery-cha ... rt-12.html

It will charge two separate batteries and do it properly. When a battery charger is used in conjunction with a battery, even a 5 amp charger (because it's running 24/7) can keep up with even moderate loads.

3) Use a converter/charger that serves as an AC distribution center, converts AC to DC, and charges your battery. I'm not sure which brands are good but this is one of the more common brands talked about on the forum: http://www.amazon.com/WFCO-WF8712P-Brow ... B004LF3A70

4) Solar power. Effective but a bit pricey.

If I were in your situation, I'd buy a good "Marine" battery. It's not the best choice for deep cycling, but a reasonable compromise. A 100 amp/hour rated battery will allow you to draw about 50 amp/hours before recharging. 50 amp/hours of juice will get you through a weekend if you "choose wisely" what you try and run. I'd buy a "stand alone" easily moved charger. If shore power is available the charger will allow you to do virtually anything within reason and not run out of juice. Go garage saleing and find an old fold-able luggage cart. This will save your back if your storage spot is far from your garage or town home. When you get home, take your battery (a couple of wing nuts to undo and a restraining strap to undo) and charger out of your trailer and take them to your townhouse or garage, put the battery somewhere out of the way, plug it into the charger and forget it till your next camping trip (but look in on it occasionally just to be safe).

What I'm suggesting is kind of what you were thinking of initially but just with bigger and better quality stuff. Moving the battery in and out of your garage or town home really shouldn't be that difficult.

Hope this helps.

Cheers,

Gus



thanks
tom
ps sorry about the lower case lettering for some reason some sights do not like to let me use the shift key very well.

[Wobbly Wheels]

...has any one used a 12v jump starter pack.

Yup, I used to use one all the time. Mine had an 18A*h battery that was good for reading lights, 12V stereo, etc and a 300W inverter to run a small LCD TV/DVD and charge phone batteries. When it gets low, just hook it up to the tow vehicle like you're going to jump it and recharge it off the alternator.

[Tomb1269]

Wobbly Wheels - Thanks, that was what I was thinking. I have see a couple that look as if you can charge and draw thru the 12v plug/ outlet on them as well. I am just looking for a little voltage / wattage for lights and fans for short periods in which I may not be hooked to the truck or have shore power. Like when loading or unloading at a Boy Scout camp in the dark.
Thanks Again
Tom B

[DriverOne]

Tomb, Auto Zone carries a 30 LED panel that replaces the shuttle bulb in automotive overhead lights. It is a significant improvement over stock (you can find black screws on gray carpeting at night!), but one of the reasons I thought to mention it is that you can stick one on any flat surface and lose no more than 1/4" headroom. Not to mention that they draw almost no power. The panel is adhered to the light housing with double stick tape after the appropriate size shuttle connector is snapped into the housing. That means at two pieces, you can make your own wiring harness without using said light housing so that they can eventually be detached if necessary. If you don't want them to be out in the open, the stick-anywhere push-style dome lamps from Walmart give you a safe and attractive housing as well as individual switching capabilities. Just my $0.02!

[Wobbly Wheels]

No sweat, Tomb.
Mine was branded as a 'PowerWattz' and when the battery finally gave up the ghost, I opened it up and took off the inverter and used it in my work truck to charge cordless drill batteries - still working today and it's got to be 15 years old if it's a day.
Last week I replaced the battery in the UPS for my computer and it was only $21 - I should have just replaced the battery and kept using it. I still have the carcass in a box downstairs somewhere so I just might add it to the 'Projects' pile....

[Toytaco2]

I just picked up one of those jump starter packs a couple of days ago to use with the trailer and other camping equipment just as mentioned. I also will have it with me on our Rocky Mountain off-roading vacation next week if we have any problems with the truck's starter battery. Its always good to have dual purpose equipment like this around.

Mike

[Kharn]

Not quite your situation but I've been looking for a power solution for tent camping, instead of the jump sarter the recommendation I've found on other forums is to put an Optima Yellowtop battery inside a battery box, bolt an inverter to the top of the box and add 12v sockets to the sides. You get a lot more power out of the unit, but you have to be careful about sizing to make sure one person can safely lift it. A pigtail with common connectors lets you charge it via battery tender at home (so the tender isn't permanently attached to the pack and you're not lugging around dead weight) or battery clips from your car's alternator while away (or a solar panel if you have the $$$; if your vehicle already has a 7-wire trailer plug, you could rig a pigtail to connect to that so you could charge without having to leave your hood open or deal with the battery terminal clips). You could use a similar pigtail set up to connect it to your trailer when in use (a re-purposed four wire trailer harness, for example, would give you 3 12v circuits plus a ground with one easy connection) plus some hold-down bolts to physically secure it.

The best instructions I've found have been on astronomy forums, usually they call it a "power pack" and use it for running electronic telescope tripods while out in open fields at night. It can also be easily used at home for lights, fan, cellphone charging, etc if the power goes out.