When I start Quicksilver, the Niehoff charges the discharged 387 a/h x 2 Rolls Batteries at around 403 amperes @ 28 volts, at 550 RPM.
But amperage falls quickly to around 315 amperes. Such is the nature of electrochemical laboratories. Saturated voltage charging reveals much about the status and health of a battery. Trends & Tendencies.
To see the characteristics of a battery saturation charging (where voltage instantly attains the voltage set point and remains there) it is most helpful to start off with a gigantic power supply. Which is impossible for most of you to lay your hands on.
Newer alternator voltage regulators are a Frankenstein's Wonderland. Nothing can be done about the way they act. They are designed to improve fuel economy. They are designed to not waterboard a misplaced battery located under the hood. For the sake of weight and copper the battery has to endure 180-210F temperatures.
Then there is the regulator itself. Tiny, cheap and forced to do more than what it possibly can. It lives on Venus except at the equator. All because connectors that would be bulletproof cost too much. As does the copper wire and the labor to install it.
It's a vast conspiracy designed to make life impossible for an RV house battery.
For newer Pons & Flieschmann aptitude charging systems the only rational answer is to install a 2nd alternator. Preferably a hairpin design that has the capability of saturation charging the battery bank. But hairpin regulators are just as stinky as other integral regulators. They need to be turned into electronic geldings. Then a decent external regulator can be used. The voltage regulator on my Niehoff is a four hundred dollar item. Tough. Snip - snip. I used a 5 conductor 16 gauge cable with 2 Molex connectors.
The system I have equals 800 amperes of charging at 12 volts. That's an aircraft carrier flight deck's worth of solar panels. I cannot boondock park at a gas station near anyone else. When that Cummins fires up it rumbles. And it stinks. And it jams more amp hours into those four batteries in a shorter time than anything else on the market.
Choose your compromise. No system is perfect and any given alternative offers superior and inferior attributes over another. The Niehoff is a five thousand dollar 140 pound brute. It even has a crane lifting eye on it. Three B belts to drive it. And the crankshaft pulley on an 855 Cummins is 12" The engine is limited to 2050 RPM high idle. But 1,390 pounds feet of torque at 1080 RPM.
I've got a crude philosophy about batteries and charging
Any energy source close to a battery in-need, gets put to work -- no exceptions.
