Aiming at the problems occurred in commission test and in operation of 10 k V post switch such as fail closing and opening

contact overheating

unreliable mechanical linkage lock

parts corrosion

inaccurate indication of closing and opening

inflexible live switching of transfer switch for the ratio of the current transformer

etc

the authors analyse these problems and give the practical improvement measures and testing methods. Experience and onsite operation verify the improvement measures so as to ensure the quality

reliability and life time of the post switch.