US Patent 7367852 Connecting and switching arrangement

A terminal block connecting arrangement includes a first terminal block having a first electrical contact, an electrical device having a second electrical contact, a test terminal block arranged between the electrical apparatus and the first terminal block for displacement between a first test position spaced from the electrical apparatus and a contact position adjacent the electrical apparatus, the test terminal block having a double-ended electrical contact. A spring-biased detent device normally retains the test terminal block in the test position. As the first terminal block is progressively displaced toward the electrical device, the first contact is brought into engagement with one end of the contact on the test terminal block. Upon further displacement of the first terminal block toward the electrical device, the detent device is released, and the test terminal block is displaced to effect connection of the first contact with the second contact via the two-ended test contact.