Thread: Charging the camper battery. Best option?

A kick ass charger will cost a bit. As soon as you get up above 1/2 doz amps your no longer in the $50 K Mart category, a 10A CTEK will set you back over $200. Honda says yes to battery charging on the EU10i, I doubt that they would say so if it was to damage your battery.

I'd save the $200 on the 10 Amp CTEK and just use the DC output on the generator if you need to top up your battery. If you are driving regularly get some nice thick cable down to the camper so your vehicle alternator can keep the batteries topped up.

The problem with using the 12V outlet on generators (including the good ones like Honda, Yamaha etc) is they are unregulated. Generally they are rated at 8 amps which in real life equals real slow. For example my charger is capable of punching in 40 amps if necessary and the 1000 generator handles it easily.

So what does unregulated mean? Well basically it is fine whilst the generator is on idle without any other load. However it won't reduce the amperage going to the battery, so you will need to keep an eye on it so you don't start boiling the battery.

When the issues arise though is when you connect another load to the generator. As the revs increase you can find the 12V outlet is now punching 16V which is obviously no good for your battery. In short the DC outlet varies with the RPM of the generator.

An old trick was to run the output through the solar regulator before connecting to the battery - it regulated the voltage to protect the battery. However you would still need to keep an eye on it because it won't reduce as the battery gets closer to being full charged.

I hope I haven't confused anyone with the above. Short answer is I wouldn't recommend it to anyone who has a charger already, which most of us do at home.


Cheers
Chris