A torque limiter assembly is disclosed comprising a housing having at least one first engagement member, an input shaft that is rotatable relative to the housing and having at least one second engagement member; and an electromagnet. The electromagnet 10 is arranged and configured such that when activated it generates a magnetic field that moves the at least one first engagement member relative to the at least one second engagement member, such that the first and second engagement members engage each other and stop or inhibit rotation of the input shaft relative to the housing.