Contract crew was energizing a new run of primary cable in a man hole. When the foreman put the switch in the closed position to take rotation at the 3 pot bank he noticed he had no voltage. He then returned to the switch and noticed it was not closed all the way. He the reclosed the switch at this time it caused a fire in the man hole at the cable. After reviewing the man hole we discovered a failed primary splice. Upon further review the cable was 25kv to 15kv where the straight splice failed. The splice used was a 25 kv straight splice. This is the incorrect splice for this cable and caused a .09’’ difference on the 15kv side of the cable causing a path to ground and the cable to slow burn itself in the clear and not a complete fault. Upon review of the other work locations adjacent to this manhole three additional splices of the same nature where located and replaced.