The HUB-4 communication manager allows the MATE to control and monitor a maximum of four OutBack products. The inverter/chargers can be operated in a stacked or independent configuration, and OutBack MPPT charge controllers can also be used on any of the four available ports of the HUB-4. Future OutBack products will also be compatible with the HUB-4. The HUB-4 manages both the inter-inverter communications and the MATE-inverter communication. The HUB-4 also can be used with the X-240 autotransformer when series stacked to allow full surge and continuous AC load capacity of each FX to be available on either of the 120 VAC output circuits. When two or more FX inverters are stacked in a parallel or series configuration, the system automatically turns off any excess slave inverters to save power and maximize conversion efficiency. This power save system is fully automatic and works with or without the MATE connected to the system One or two MATE system controllers and displays can be connected to the HUB. One Mate is allowed to program the systems while the other MATE is able to only control and display the system operation. When using a single MATE with a HUB-4, programming can be locked out by moving the MATE from the 1st MATE port to the 2nd MATE port once programming has been completed. The maximum distance from the HUB-4 to the power conversion product should be under 10 feet. OutBack includes two 3 foot long and two 6 foot long CAT5 cables standard with the HUB-4.