A surgical instrument includes a temperature sensor and a control unit that is operable to deactivate an end effector of the surgical instrument. In some versions the temperature sensor detects the temperature of a transducer, while in others the temperature sensor detects the temperature of the end effector. The surgical instrument may also include a trigger and a trigger position sensor. A force sensor or a position sensor may be included to determine the force and/or position of the transmission assembly. The end effector may also include a force sensor or a micro coil. A surgical instrument having a sensor may be included in a surgical system that includes a control unit and a remote controller. In some instances the remote controller may have one or more force-feedback components. In addition, a device interface and a surgeon interface may be included to remotely adjust the settings of the control unit.