Determining operating times and logical timing relations by state-based sequences
State Sequencer is a very flexible test module for determining operating times and logical timing sequences. A state is defined by the output conditions (voltages and currents, binary outputs) and a condition for the transition to the next state. Several individual states can be put together consecutively in order to define a complete test sequence. The transition from one state to the next may take place after a fixed time, after the occurrence of a trigger condition at the binary inputs of the CMC, or after a GPS or IRIG-B trigger (e.g. for synchronized end-to-end testing with multiple CMCs). Looping of the sequence or static output of individual states is also possible.
Definition of individual states
Within one state, all configured test signals (voltage and current outputs) of the used test device can be set independently in amplitude, phase, and frequency. Besides the direct input of the individual voltages and currents, the integrated Fault Calculator allows the automatic calculation of the test quantities. These can be entered as fault values, power values, symmetrical components, or impedances (with constant test current, constant test voltage or constant source impedance model). For distance relays, test points can directly be defined in the interactive impedance plane showing the nominal characteristic of the test object.
Time measurement conditions can be defined to check the correct operation of the relay. Individual response times and tolerances can be specified for each measurement condition, allowing a fully automatic assessment of the results. If the measured time is within the tolerance range, the test is “passed“; otherwise, it is “failed“.
Apart from timing measurements (always triggered by an event, e.g. a trip) state assessment(s) can be made. A state assessment is positive, if defined states at the relay outputs connected to the binary inputs are logically true throughout a certain state.
Assessment and reporting
The measurement conditions are displayed in a table. After a test execution this table also contains the actual measured times and deviations and the automatic assessment of the results. The last column contains the “passed“ or “failed“ information. All of the time signals (voltages, currents and binary inputs) can be displayed graphically to aid in studying the reaction of the relay. Signals can be enabled individually, with the ability to zoom in on specific points in time. Data cursors facilitate scrolling through the time signals to find the values at specific times.
This module is part of the Test Universe software. For more information please refer to the Test Universe website.