The 864e is an input and output expansion module for use with the P864 controller. It can be expanded to a total of 144 hardware points using a P864 and by adding up to 7 additional 864e modules. The P864 controller can directly control 864e inputs and outputs. The P864 controller can host control logic, schedules, trends, alarms and is expandable using the 864e expansion modules up to 144 hardware data points. The P864 stores all 864e data into memory in the event of power interruption. Normal operation resumes after power is restored.