Functional Principle

Figure 1

ITS Test Block is in normal operation. Currents and voltages from the power system are being fed to device through the Test Block. ITS Test Plug has not yet been inserted.

Figure 2

ITS Test Plug contacts are now touching the ITS Test Block contacts. Currents run only through the A side of the test plug and are safely shorted across shorting bars achieving a "make before break" operation. The Test Block contacts are still not open and currents and voltages are still being fed to device.

Figure 3

ITS Test Plug is now fully inserted into the Test Block. Power System currents and voltages are safely redirected to the A Side of the plug and are no longer being fed into device. With device completely isolated, secondary injections can now be made using the B Side of the Test Plug.

Automatic Operating Sequence

Upon insertion, the SecuControl ITS performs a 4 step automatic operating sequence. When the Test Plug is inserted, the trip circuits are first opened by the longer pins, followed by the shorter pins that automatically short the CT circuits via the internal shorting bridge. Voltage circuits are then redirected through the plug and test procedures are ready to begin. When the plug is withdrawn, the circuits are restored in the reverse order beginning with step 4 of the insertion sequence.

The automatic operating sequence simplifies the job of the technician. Proper isolation and restoration of the device being tested is achieved every time. Costly false trips and errors in CT short-circuiting are no longer a concern with the ITS.