A device and method for adjusting the magnetic strength of a magnetic end effector for lift systems is described. The magnetic end effector is capable of lifting discriminate payloads by selectively varying the strength of the magnetic forces output by the magnetic end effector. An actuator can be operatively coupled to the variable strength magnet end effector, wherein the actuator is selectively actuatable to control the adjustment of the variable strength magnet. The actuator may also be configured to maintain the variable strength magnet at a desired magnetic force output strength once achieved for any given amount of time.