Thread: 24/7 camper trailer battery charger

Hi Pedro, first off, change the fuse to a 10 amp. This will still blow if you get a short in the system but it won’t heat up, which the 5 amp will.

Next, the batteries only need to be charged one day a month for about 24 hours but you need to keep and eye on the voltage at the battery while charging.

If while the batteries are being charged, you notice the battery voltage goes up over 14.5v, disconnect the charger.

Arlec chargers have a bad habit of going way over voltage once the batteries are fully charged and while the Allrounders will take this far better than gel or AGM batteries, they will eventually cook.

Cheers.

so, one day a month rather than a little every day,,,

and yea,, I've had the charger for a while,,
thought it might have just trickled away quietly
damn.

probably just didnt want to buy a new one and destroy it

hmm,, can i run a timer off a timer??---

yes, It could run of a timer. Get a teliphone reminder call once a month to tell you to turn the charger on. Just kidding.

I run a compressor off one of those timers up at the clubhouse so I think your charger should be fine.

Ive got a similar set up for a buggy with lights for changing holes in the dark.

It has a start gen so only starts on demand and shuts off when stopped so I run a second deep cycle battery to run the lights and just charge it once a week.

The charger I have at work I have cut the alegator clamps off and just with a bit of 6mm 2 core I have fitted a Hella "T" shaped plug on the lead from the charger and on the leads from the Alegator clips as well as the 2 core which has an Anderson plug at the other end which plugs into the Buggy on the roof frame.

Works a treat and I have faced the anderson plug forward so that when the guys take off with it still plugged in it just pulls out with out ripping everything apart.

I tried to put them into photobucket but my account wont upload shots for some reason so Ive put them in as thumbnails.

Drivesafe, The deepcycle is meant to be charged to 14.8v but the charger (from a powered pedestrian golf buggy) only charges to 14.5v, I know this will shorten the life of the battery but is there a charger out there that can be set up to charge to 14.8v and just shut off, no trickle charge?

Hi mcrover, actually, your batteries will probably have a longer life when charged at 14.5.

14.8 is actually just above the maximum charge voltage for flooded wet cell batteries ( like Pedro’s Allrounders ) which should not exceed 14.7 and most sealed, gel and AGM batteries should not be charged with anything higher than 14.4.

It’s always best to check the exact specs for any battery by going to that battery’s manufacturer’s web site.

Originally Posted by drivesafe

Hi mcrover, actually, your batteries will probably have a longer life when charged at 14.5.

14.8 is actually just above the maximum charge voltage for flooded wet cell batteries ( like Pedro’s Allrounders ) which should not exceed 14.7 and most sealed, gel and AGM batteries should not be charged with anything higher than 14.4.

It’s always best to check the exact specs for any battery by going to that battery’s manufacturer’s web site.

Yeah I thought it was a bit strange but thats what it clearly says on the battery........This battery must be charged at 14.8v.......So ive been going out of my mind looking for a charger that will charge at a reliable 14.8v and not swing all the way up to 15 odd volts or no lower than 20v.

Im not sure on the brand of the battery, just got it from R&E autos and chucked it in.

Ok well I will leave that charger on it then and see how it goes.

The last one lasted a bit over 2 years and it started off in a box that got thrown in and out of the back of the buggies, at least this one is mounted properly.

I was using something similar for a while but it was a bit messy.

I was given one of these by the in-laws for my birthday. I thought it was a bit small for what I was charging (125AH battery for fridge) but it really rocks!

- Sealed Lead Acid (SLA) Chargers : BFA012 : 12v Battery Fighter 4 Stage 1.25A

Originally Posted by Pedro_The_Swift

Being a basically lazy person, I had to think up a charging system that took minimum effort,, and "running wot I brung" bits and pieces.
Being an inside/outside system I needed to bring the charger inside out of the weather, so a 5 meter extension lead had its ends lopped off, the active and neutral joined and bits soldered on the ends.


I thought I could use the one charger for the camper on a semi permanent basis, and by adding the inline fuses I can "change ends" to the original small battery clamps. All joints are soldered, even some heat shrink made an appearence!
The timer is rated at 10A,, but with a 4 amp charger and 5 amp fuses it should be fine,,
There is no voltage drop between the anderson plugs and the charger.

The only problem so far is the charger is "reading" the battery condition 23/7.
Dunno if this is a problem,,??

also any guesses on a daily charge time?

The batteries in question are two supercharge allrounders
MRV87 825 CCA's

current() voltage is 12.36

Hi Pedro,

The timer is a good idea as this will prevent overcharging & subsequent electrolyte loss. 4Amp is the DC output of charger. The actual AC current that timer has to switch would be less than half (.5) Amp.
Leaving charger connected to battery when timer is off shouldn't cause any measurable drain as diodes in charger should prevent this. If charger has LED charge indicators which illuminate with mains disconnected the there will be slight drain on battery.
If you want a charger that doesn't require timer & will charge batery fully without overcharging check out Smart Logix 12v Automatic Battery Charger. These are 4 stage 16Amp & designed for AGM, Gell Cell, Deep cycle & Marine batteries.
These are sometimes available from BigW for less than $100

cheers..Bruiser