AC Coupled Pre Wired Systems
If the utility grid goes down, so does your grid-tie system. This is because a grid-tie inverter feeds excess power back into the utility grid rather than into a battery bank, which is very dangerous if the grid is down because someone is working on it. An AC Coupled system can add battery backup to your grid-tie system, allowing you to take advantage of the benefits of net metering while still receiving limited power during an outage.
AC Coupling is a controlled back-feed to a battery based inverter developed by Midnite Solar. Because a back-feed is hooking up AC to the output of an inverter, it comes as not surprise that normally this will destroy your inverter. However, an AC Coupled system shifts the frequency to match the battery based inverter before connecting, which prevents damage to the inverter.
AC Coupling is available for the SMA Sunny Island, the Outback FX, VFX, and Radian, the Magnum PAE series, and the Schneider Electric Xantrex XW Series.