Abstract: A terminal block assembly includes a slip-on module removably connected at one end with a terminal block housing, characterized by the provision of a separating device mounted at an accessible point of separation location at the other end of the module for electrically connecting and disconnecting a circuit interrupting device between a pair of terminals on the module respectively. The separating device includes a lever pivotally connected for movement between connect and disconnect positions relative to the slip-on module, the module including projecting portions for partially concealing the lever when in the connect position, thereby to prevent inadvertent displacement of the lever to the disconnect position.