Sequence of Operation – The Super Star Feature of ETAP STAR

If you are a user of ETAP then you may be familiar with STAR, the module for doing protection and coordination studies.

The STAR module is capable of drawing the Time Current Characteristics (TCC) of protective devices next to the operation, or damage curve of electrical equipment such as motors or power transformers.  The display of device TCC side by side with protected equipment curves, for visual comparison and making proper adjustments, is the industry standard for protection and coordination studies.

Such practices may not lead to proper adjustment or verification of overcurrent protective device settings if you have parallel sources of supply or looped connections in the electrical network. That is where the ETAP STAR module goes beyond expectations and is equipped with a super star feature called Sequence of Operation.

You can place any fault type, balanced or unbalanced, at any desired location on the modeled electrical network and graphically observe the Sequence of Operation (SQOP) for available protective devices. The graphical display of SQOP on the one-line is a perfect solution for verification of existing or designed coordination, supplemented by reports to give the exact trip and operating time for each of the devices.

The beauty of SQOP is in the application to any network connection topology, looped and/or multiple sources of supply, and support for other protection functions such as ground, differential, negative sequence, etc.

The following link on the ETAP Web site can be visited for further review of the SQOP feature in STAR or you can refer to chapter 16 of ETAP help file.

http://etap.com/protective-device-coordination/protective-device-sequence-operation.htm