comments:
Just fyi, I have not looked at anything else on this page, like wire sizes or anything. Only this 12V 30 amp output thing. Using a 12v battery on the 12V DC theoretically does help mitigate the current overload in theory, it's not a good or proper solution. There are several problems with this: the 12V DC output is a FLAT 12.00V (or close to it.) all batteries vary their voltage based on how much charge they've got. Since the 12V output is always exactly 12V, it basically won't be charging the batteries at all beyond 20-30%. Even lead acid batteries want to be around 12.8V most of the time and deplete the longer they are held at a low voltage. Lifepo4, the most common battery for this sort of application, wants to sit around 13.6V when at a full charge, but sitting at 12.0V means like 5%. Only a sodium-ion battery would work here, as 12V for them means ~50%-ish. Not to mention, there are some problems with "charging" many batteries like this, as the vast majority of batteries do not "want" to be held at a flat, low voltage for long periods of time. Using a battery in parallel with a DC output only helps prevent currently overload if 1) the total current draw is less than some certain amount (would have to calculate based on circuit resistance and battery size), and 2) the battery has enough charge. once the battery dies juuust far enough, it will overload the 12v 30amp output and trip. connecting your external battery straight to a 12V output is not a good idea if the battery starts out dead and at very low voltage (like a lead acid battery). It will suddenly draw a TON of current based on the internal resistance of the battery itself. Even if its just a split second and would be safe for the wires, it will likely trip the 12V output. The proper solution is to use a 12V DC-DC charger that is either below the 30 amp rating, like this: https://www.amazon.com/Victron-Orion-TR-Isolated-Charger-Supply/dp/B0851TPKV7 or fully adjustable, like this: https://www.amazon.com/Generic-DC-DC-Charger-Victron-ORI121217040 This DC-DC charger takes your pecron's 12V 30 amp port, and charges the external battery intelligently. Then your external battery powers your devices, which connect to the blue sea 250 amp bus bar. This DC-DC charge trickle charges your external battery all the time, ensuring. extra current drawn *can't* come from the pecron unit. This is the proper solution to this problem.