I have an idea here guys and I'm hoping some of the experts out there can help me out.

I bought one of these battery boxes to use with our SAR team:

Trolling Motor Power Center

It has 2 12v cig lighter ports (wired to a 10a breaker) and the terminals are wired to a 60a breaker.

Also has a built in charge checker and fits group 24 and 27 batteries.

My idea is to use the cig adapters to recharge phones, etc. and wire our HAM radios to the terminals (since they are 50w transmitters) while we refuel generators, etc. or for short setups as we are 'on the run' (say doing an open field search, etc.).


So I've had this since just before Christmas and now I'm going to get a battery for it this weekend. As I stared at this thing for a few weeks, I'm wondering if I could also use this in another way.

We have 16' box trailers with ramps on the back - they get pretty slick when a fine layer of dust gets on them or when it rains. We also have a 7' long, 22" wide, 5' tall wheeled cart that we load onto our trailers...weighs maybe 700lbs. It carries our Operations tent, small inverter generator, printer, light kit, etc. etc.

We've seen our guys struggle getting footing on the ramp in certain conditions, so the idea was why not get a small winch like you'd mount on an ATV, connect it to the on-board trailer battery and just winch it up using a block when it's wet or dusty out?

I found a Harbor Freight winch...bought the 3500lb since it was only $20 more than the 1500lb and had a faster spool rate. Here is the manual for it:
http://manuals.harborfreight.com/man...1999/61257.pdf

SO...my questions are:
1. Do you think a group 24/27 battery would be able to power a winch that size without killing the battery in one pull? I have no idea how battery group size relates to amps...and if I should get a certain type of battery based on using it for this. Keep in mind we'd use it to either lower the cart down (should be minimal power required since it's just "braking" the cart) and pulling it up the tailgate ramp of the trailer (I'm picturing the wheels butted up against the ramp, then pulling it up the ramp and into the trailer...maybe 20 feet total distance, maybe 2' in elevation over a 7 foot distance, then level the rest of the distance).

2. If I want to also use this to run a radio (a Yaesu 857d), could that same battery perform the winching operation detailed above, or do I need two different types of batteries (deep cycle vs. ...whatever other kind).

The plan is when not in use to connect it to one of those 'Battery Tender' type deals that charge then automatically shift to float...

As you can see, I don't know jack about batteries. My initial idea was to wire in connectors to the trailer batteries, but if this box can perform both functions, I'm thinking why should we spend that money (wiring) for 5 trailers when I can just get 2 of these and have both rolling carts covered.

So...battery gurus...educate me!

 

on page 2 if the load is 1000 lbs its pulling at 14 ft per minute drawing 80 amp. Thats about 3 inches per seconds that seems extremly slow. With a fully charged deep cycle battery 240 to 300 amp reserve, maybe 6 pulls before the battery is very weak.

 

My plan was to use a block...that should double the line pull speed...and the load in total is 700lbs...but on wheels up a sloped ramp, the pull weight should be a lot less.

When the ramp is dry/clean I can push it up the ramp myself...let's be generous and say its 300lbs of force? Double that with a block would be 600...

Also...keep in mind that the odds of using it to lower the cart would be slim...it's loading the cart that's tricky...and seeing as it is something you don't really move very often (the tent is 16' around...we do t move its after its set up unless we have to), we'd have time between each pull to recharge the battery (if the tent is set up, the generator is too, and we can easily handle lights, computers, etc. along with the charger).

Knowing we can charge it between pulls...do you think this is doable, or should we find a manual winch of some sort?

 

Yes it would work, well worth it if it saves a back or other injury! Over 20 ft per minute low/no load and only 20 amp draw. Recharging between uses is a plus.

 

Not a battery Guru, but worthwhile to ready everything you can on winching safely.

http://www.warn.com/corporate/images...PN62885-A2.pdf