Removable magnetic zero/span actuator

摘要

A magnetic actuator (100), for adjusting the zero and span settings of a transmitter (10) used in industrial process control systems, includes a single magnet (110) in a housing. The actuator (100) is removable from the transmitter (10). When the actuator (100) is unactuated, the magnet (110) is in a null position wherein it does not actuate either of zero or span setting reed switches (18,20) in the transmitter (10). The magnet (110) can be moved either to a first position wherein it actuates the zero setting reed switch (18) or to a second position wherein it actuates the span setting reed switch (20). The actuator (100) applies a torque in the required direction to return the magnet (110) to the null position when the torque applied to move the magnet (110) to either the first or second position is removed.