An apparatus for splicing optical waveguides has a memory circuit in which data items which identify a state of the apparatus for splicing the optical waveguides are stored. The stator slots extend from a radially outermost yoke part of the stator core radially inwards towards the rotor, the stator slots being separated by teeth. The method comprising: weighing the composition for a sensor element; mixing the composition; calcining the mixture at about 1000\xb0 C.