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 I have purchased a solar panel trickle charger to keep the battery topped up whilst in storage and to maintain the power for tracker system installed.

The unit comes with a 12v plug for use in a 12v socket. So if I plug it into 12v socket leave the battery switch left 'on' for the van when in storage to maintain the charge and ensuring all 12v appliances and lights etc were switched off would that be ok, or do I need to switch the factory installed caravan charger on as well?

The unit comes with a 12v plug for use in a 12v socket. So if I plug it into 12v socket leave the battery switch left 'on' for the van when in storage to maintain the charge and ensuring all 12v appliances and lights etc were switched off would that be ok, or do I need to switch the factory installed caravan charger on as well?

WELCOME

sorry for the confusion,are you not asking the battery to charge itself up by plugging it into a 12v socket in the caravan.the battery charger will only work from ,mains and from the car when the engine is running.you need to buy a second battery charge it then swop over after a few months.

this may help

http://www.selectsolar.co.uk/faq.php#faq9

Peardrops,

Your battery discharges for two reasons:

Internal discharge - this can be around 5%/week for a Leadacid battery, and gets worse as battery ages or as temperature increases.

External discharge - loads placed across the battery. This could be deliberate, ie your tracker or lighting etc, or accidental (the output resistanceof the charger).

Without getting too complicated, you really need to know the power consumption of your tracker unit and the internal discharge of your battery.

A quick search on the internet suggests your tracker probably uses around 10-15mA on standby.

Trickle charging current is typically used to replace internal discharge. This is typically 0.5mA to 1mA for a Lead acid battery. If your battery is 110AH  then you will need 55mA to 110mA to maintain the battery with no load.

Add the 10-15mA for your tracker and on a good condition battery you would probably need around 65-125mA.

However you say your solar panel is capable of 2Watts (165mA at 12V). This may be true on a bright sunny day with the panel pointing at the sun, but will probably be significantly less on average as Soundsdigiat points out earlier. The only way to be sure is connect it and monitor the battery voltage over a few weeks. Do this with the panel DISCONNECTED, and prefferably after the battery has settled for a few hours.

Battery voltage is a crude method of measureing battery charge status, but by checking it periodically you should not see a drop in voltage over a period of weeks. A guide is 12.7v for a 100% charged battery and 12.4V for a 75% charged battery. A cheap digital multimeter will do this easily.

Hope this helps

regards

PS The 12V socket should be connected to the battery directly. You should not switch on the charger.