theoldwizard1 wrote:
Photomike wrote:
On that subject during the build of my vans electrical system I had the opportunity to talk to one of the suppliers of battery to battery charging systems. He gave me lots of information that I never knew but one point that he made is that many people operate on the wrong assumption that we are doing things outside of what a vehicle or a boat for that matter is designed to do with charging. In fact it is the opposite - a charging system is designed to charge and will do so as long as we do not do something stupid and it will do so with a number of batteries as all batteries will equalize in a system and charge from that point. The charging system does not know if you have 5 batteries at 12.5v or one, it will take longer to top up but it is doing the same thing as it was designed for.
I am sorry, but that person is living in the past ! And fairly DISTANT past !!
Smart charging systems are designed around the assumption that they only have to recharge the ONE (or possibly two) batteries installed by the OEM. The have knowledge on what the "capacity" is of that size battery back. They know (approximately) how much energy was used to start the vehicle. They know (approximately) how much power is being used by accessories and adjust for it. They even understand short, high load (electric power steering).
An auxiliary battery bank will look like a parasitic draw. The system will compensate for it (increase voltage slightly) but not enough to re-charge a house battery bank at 50% state-of-charge.
Old regulators worked on the principle of "the battery voltage is low, charge at max rate." The new one basically says (after replenishing the energy from starting), "the battery voltage is low, charge at a rate that will not let is discharge any more."
So you're saying "smart" vehicle charging systems are not capable of handling large or small accessory electrical loads like a snowplow, ambulance needs, camper battery charging, winch, etc?
Wonder why they even offer the convienent upfitter switches on some models... By your analysis, anything more than the OE equipment will not be "considered" for recharging.
I don't believe this is the case. Ask all the dudes with new trucks and dedicated accessory charging/loads that are/were installed after the truck left the assembly line.
