Battery charging-

[mistralse]

Has anyone used an inverter to operate caravan charger via mains input?In theory it should work as long as you take the car out most days.

 

[Bob_5041516]

Why not simply put the caravan battery in the boot and connect into the car's 12 V rail when you are out and about? This avoids the double loss of efficiency converting to mains then back down to 12V. If you want to be pedantic, connect it via the split charge relay that feeds the caravan charge to the caravan when you are towing.

 

[JamesWatt_5040801]

An invertor produces ac (normally 240v)from dc (normally 12v). You therefore can't charge a battery from an invertor, because it's designed to give you a "mains" supply when you haven't got one.

It is feasible to connect an invertor to your cars battery and run a battery charger off it (which is what I think you are asking).

Would it work? Yes of course it would - but the load on your car battery to achieve a decent charge might be too musch for it. It's more embarassing to have a flat battery in the car than it is in the van.

How I remember gas lamps, foot pumps, gas fridges, Tilley lamps . . who needs electricity>

 

[Pete4]

Hi,

I've been experimenting with this for some time now.

You can charge the leasure battery using a batter charger plugged into an inverter that is running off the car battery. No problem.

I had the idea some time ago of hooking the 'van upto the inverter. The idea being that I could top the leasure battery up each time I visit the 'van for maintenance(pottering about). Also, it would be a good way of filling up the battery from the car when without mains electrics. The car battery shouldn't get too low as the inverter will cut off when the donor battery voltage starts to drop.

I'm not sure on how the zig unit works though. I hooked the 'van to the inverter and turned on the zig unit along with a few lights. I expected the inverter to come under load, but nothing happened. The battery was in good condition and took little from the charger.

I'm not sure, but I think the zig unit takes very little mains wattage regardless of the demand for 12 volt amps, any deficit (which happens when even the smallest light is turned on) is taken from the battery, this is then replaced at trickle rate at night, when all is turned off.

The short answer is "yes". If you're looking to quickly top up, I'd use a charger though and not the zig unit.

Also, note the charger should also be a trickle charger and not a booster thingie as they tend to bend the plates on leasure batteries.

 

[Chris4]

An inverter only approximates the sine wave produced by true alternating current mains. Some devices will therefore not work with them. I would suggest that a charger would need a fairly clean ac supply to then convert it into 12v direct current. They are also quite inefficient. I would get a voltage regulator of the type used to charge a battery from a 12 volt solar panel. It will prevent overcharging and prevents the car drawing power from it. Plug the regulator into a 12 volt supply on the car and connect the battery to it. Much more efficient. Make sure the battery is secure in the car and well ventillated.