SPDT: Single-Pole Double-Throw 单刀双掷其它触头类型如下：SPST: Single-Pole Single-Throw 单刀单掷DPST: Double-Pole Single Throw双刀单掷DPDT: Double Pole Double Throw 双刀双掷
SPDT-- 单杆,投掷SPDT 单杆,投掷 Single Pole, Double Throw
