Patent ID: 7941294

Claim:
An apparatus for detecting a condition in a fluid delivery system, said apparatus comprising: a motor control configured to provide electric power to an electric motor; a logic circuit in communication with the motor control; and a memory in communication with the logic circuit, wherein the memory is configured to store a first rate threshold associated with a register condition; wherein the logic circuit is configured to (1) determine at least one motor parameter at a plurality of different times, and (2) compute a rate of change value in the at least one motor parameter, and (3) determine a register condition if the computed rate of change value exceeds the first rate threshold; wherein the at least one motor parameter is system current, system power, system efficiency, motor current, motor power, or motor efficiency; wherein the system comprises a filter and wherein the memory stores a nominal motor parameter value and a maximum motor parameter value; wherein the logic circuit is configured to compute a filter life parameter based on the nominal motor parameter value, the maximum motor parameter value, and the at least one determined motor parameter; and wherein the system comprises a register and wherein the logic circuit is configured to adjust the nominal motor parameter in the memory to account for at least one determined register condition.