The van has an unusually high battery capacity and unusually high power delivery capability. It's a 800AH bank of 24 volt batteries. Equivalent to 1600 amp hours at 12 volts or 19,200 watt hours.
We have the ability to pull 8,000 watts continuously from the batteries with 10,000 watts peak We're using dual Victron Quattro inverters:
Similar to the MultiPlus, the Quattro is also a combined inverter and charger. Additionally, it can accept two AC inputs and automatically connect to the active source. Its many features include a true sine wave inverter, adaptive charging, hybrid PowerAssist technology plus multiple system integra
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It's a film truck with quite a few 20 amp AC circuits inside and out that let us fully utilize the available power. So it's quite possible for us to run them down to zero in just over 2 hours.
At 3KW alternator output it'll take over 6 hours to charge them up assuming 100% efficiency, so maybe more like 9 hours.
Typical use will be driving to shoot location, parking and turning off van. Using the heck out of the batteries and hopefully not running out of juice. Then packing up and driving to home base. Supplementing any remaining charge time needed with shore power on arrival back at home base.
She'll be doing quite a lot of highway miles for remote shoots - over 1000 mile trips regularly. So we may see for example a 6 to 9 hour charge time for an entire day trip leg. And then have that scenario repeat fairly often.
~Mark.
Edited for clarity.