Avoiding operating errors during operation is a top priority here, as they can have serious consequences for personnel and equipment. For this purpose, the Klippon^® Connect TTB Series instrument transformer terminals feature a unique disconnect lever mechanism, the "Make-Before-Break" contact. It increases system availability and extends the life cycle of the entire switchgear. An IEC 60947-7-1 Annex D approval underlines the quality claim.

New forced short-
circuit functionality

The TTB Series instrument transformer terminals have been specially developed for use in secondary circuits of measuring transformers. For safe application when disconnecting or isolating protection and measuring devices, the terminal short-circuits the current transformer and thus prevents high voltages from occurring in the secondary winding. One of the most important advantages of the new transformer terminal is the "Make-Before-Break" contact for up to four connections. It ensures that the current transformer within the terminal is short-circuited before it is disconnected from the rest of the transformer circuit. This prevents the voltage at the current transformer from running up and protects it from damage or even destruction. After short-circuiting the CT side and simultaneously disconnecting the primary side, the meter/relay can be easily and safely replaced or a comparative test can be performed in full safety. The combination of disconnecting lever, short-circuit bridge and lever link in a single system, i.e. the forced short-circuit functionality, guarantees particularly simple and safe wiring.

Safe comparison measurement

It is just as easy, for example, to connect a reference measuring device for a comparative measurement. Thanks to the patent-pending CM (Comparative Measurement) lever connection, two terminal blocks can be selectively disconnected in order to interconnect a calibrated measuring device.