Complex sentence: One member of the class no.302 (302302) was experimentally fitted with thyristor control in the early 1970's after the experiment it was converted back to original tap changer control although the guards van remained slightly different internally.
Split into simpler sentences: One member of the class, 302 302, was experimentally fitted with thyristor control in the early 1970's. After the experiment it was converted back to the original tap changer control, although the guard's van remained slightly different internally.