madmaths
Observer
Hi! the more I read on this subject the more I'm confuse about this! And I should know the answer I'm a electromecanic and a industrial electrician... any way I'm not 100% sure so I'm looking for some good answer please. Some say its very dangerous to but not the same rating, type.... battery in parallel, some say use a isolator other say don't because they are diode and they have voltage drop , some say use a 12v to 12v charger other say use a solenoid....... Jesus!!! I would like to have you 2cents on this subject please! I just read here on adventurervctr.com a article and I'm very not sure if I agree here a copy and past :
The first four segments will deal with electrical TRUTHS and MYTHS in nature.
When towing my trailer down the road my tow vehicle will "charge" my trailer battery.
MYTH: Actually, your tow vehicle doesn't know there's another battery in your trailer only that there is a 12V load of some sort. Look under your tow vehicles hood and find the charge line from your tow vehicle's alternator to it's battery. It is a very heavy cable capable of handling very high amperage, 60A or more. The so called"charge line" from your vehicles battery to the 7 pin connector at the back is in relation a very small wire, carrying only a few amps. Your tow vehicle will supply 12V at low amps to the trailer should the trailer battery be dead to help put the slide in for example or to help supplement the 12V usage on board the trailer when traveling as in the case of running your refrigerator on 12V. The tow vehicle sees this "charge line" as just another 12V outlet, similar to a cigarette lighter. There are in fact only two effect ways to charge your battery on board your trailer. That is by either plugging the trailer power cord into a 110Voutlet so that your on-board converter chargers the battery or by removing the battery and putting it on a true "battery charger". The latter is the quickest but your converter will do a good job as well. It will just take longer.
The first four segments will deal with electrical TRUTHS and MYTHS in nature.
When towing my trailer down the road my tow vehicle will "charge" my trailer battery.
MYTH: Actually, your tow vehicle doesn't know there's another battery in your trailer only that there is a 12V load of some sort. Look under your tow vehicles hood and find the charge line from your tow vehicle's alternator to it's battery. It is a very heavy cable capable of handling very high amperage, 60A or more. The so called"charge line" from your vehicles battery to the 7 pin connector at the back is in relation a very small wire, carrying only a few amps. Your tow vehicle will supply 12V at low amps to the trailer should the trailer battery be dead to help put the slide in for example or to help supplement the 12V usage on board the trailer when traveling as in the case of running your refrigerator on 12V. The tow vehicle sees this "charge line" as just another 12V outlet, similar to a cigarette lighter. There are in fact only two effect ways to charge your battery on board your trailer. That is by either plugging the trailer power cord into a 110Voutlet so that your on-board converter chargers the battery or by removing the battery and putting it on a true "battery charger". The latter is the quickest but your converter will do a good job as well. It will just take longer.