Patent ID: 8213150

Claim:
A controller for a solenoid of an electromechanical lock, wherein the solenoid has a solenoid plunger and generates motion power to move the solenoid plunger and holding power to hold the solenoid plunger in place, and the controller is operative in accordance with a method that comprises: a. generating electrical power associated with motion at a first power level during a first interval and a third interval to cause the solenoid to move the solenoid plunger and generating electrical power associated with motion at a second power level during a second interval, between the first and third intervals, to cause the solenoid to move the solenoid plunger wherein one of the first and second power levels is a higher power level and the other of the first and second power levels is a non-zero lower power level, and either b1. interrupting generation of electrical power, repeating step a, and generating electrical power at a substantially constant power level to cause the solenoid to hold the plunger in place, or b2. generating electrical power at a substantially constant power level to cause the solenoid to hold the plunger in place, and wherein the controller generates electrical power at the first and second power levels by pulse-width modulation.