Converter and Battery Question
Hello all, I plan on installing an inverter in my travel trailer in the near future, as well as moving my battery from outside the trailer to the front storage compartment to minimize the distance ...
Forum Discussion
The battery can be grounded to the frame wherever it's convenient to do so. With a solar controller, that doesn't need to change for any reason; the battery negative side of the controller can likewise be connected to a convenient chassis ground location (not necessarily the same one as the battery). The frame does provide a good, low-impedance path for the current, provided the connections to it are good and clean and tight. You'd be hard-pressed to create a better, lower-impedance connection with a wire in most cases.
Any halfway modern system will basically have the converter, the battery, and the DC fuse panel connected in parallel, ignoring the battery disconnect switch for the moment. This may be physicallly accomplished by having the converter connect to lugs on the DC distribution panel, basically making it be the junction point for all three, but electrically it's equivalent in theory. Others have the converter wired more or less directly to the battery lugs, or perhaps to some intermediate bus bar or other junction point. In any case, the converter does supply power not only to the battery but to the rest of the 12V system when plugged in, since they're all interconnected. A standard battery charger clamped to the battery would do the exact same thing, for the same reasons. You continue to have 12V power when unplugged simply because the battery is now carrying the load, and you have a working battery.
The specific details of what connects together physically and in what locations is somewhat more variable than the basic electrical setup. Fiddling around with those connection points is perfectly reasonable, provided of course you employ appropriate electrical safety practices, such as making sure sufficient overcurrent protection (fuses) are there for the circuits you reroute.
It is perhaps worth observing that modifying the converter connections may alter how the system behaves if the battery disconnect switch is used to disconnect the battery. If the converter is connected to the electric panel (or anywhere on that side of the switch), then it will power the 12V system when the battery is disconnected but not charge the battery. If it's on the battery side, then it would charge the battery but the 12V system for the RV would have no power. Neither one is especially desirable in most situations.
Any halfway modern system will basically have the converter, the battery, and the DC fuse panel connected in parallel, ignoring the battery disconnect switch for the moment. This may be physicallly accomplished by having the converter connect to lugs on the DC distribution panel, basically making it be the junction point for all three, but electrically it's equivalent in theory. Others have the converter wired more or less directly to the battery lugs, or perhaps to some intermediate bus bar or other junction point. In any case, the converter does supply power not only to the battery but to the rest of the 12V system when plugged in, since they're all interconnected. A standard battery charger clamped to the battery would do the exact same thing, for the same reasons. You continue to have 12V power when unplugged simply because the battery is now carrying the load, and you have a working battery.
The specific details of what connects together physically and in what locations is somewhat more variable than the basic electrical setup. Fiddling around with those connection points is perfectly reasonable, provided of course you employ appropriate electrical safety practices, such as making sure sufficient overcurrent protection (fuses) are there for the circuits you reroute.
It is perhaps worth observing that modifying the converter connections may alter how the system behaves if the battery disconnect switch is used to disconnect the battery. If the converter is connected to the electric panel (or anywhere on that side of the switch), then it will power the 12V system when the battery is disconnected but not charge the battery. If it's on the battery side, then it would charge the battery but the 12V system for the RV would have no power. Neither one is especially desirable in most situations.
