The AE Series of PRIORITIZER can be wired into a service panel, master fuse block, or directly to the load wiring, whichever is the more convenient based on existing wiring. The drawing shown is based on wiring into a service panel. Make the appropriate changes if necessary to wire in some other fashion.
In this typical alternative energy application of an AE 1110-20 unit, we connect a Sump Pump (breaker #7) into the Priority 1 line, a Refrigerator (breaker #8) into the Priority Two line, and a 240v volt Water Heater (on breakers #4 and #5) into Priority 3. Note that we are only switching one leg of the 240 volt line. Check with your electrician to see if this can be done in your application. The water heater will be disabled when any of the loads connected to P1 or P2 draws current, and will be permitted to operate when both the P1 and P2 loads are off, which will occur periodically throughout the day and night.
Notice that while originally the electrical wire went from a given circuit breaker to the associated appliance (say a Refrigerator), now that same wire runs through the PRIORITIZER on its way to the load, so that the PRIORITIZER may either monitor the current being used by that appliance (P1 circuits) to see if it is running, or temporarily disconnect that wire (P2 circuits) when required.