GE Multilin F650, Инструкция по эксплуатации

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CHAPTER 5: SETPOINTS 5.4 PROTECTION ELEMENTS
GEK-106310-AF F650 DIGITAL BAY CONTROLLER 5-47
Figure 5-4: Table change signals configuration example
The example above uses six digital inputs to perform the table selection, but it is possible to use any other logic signal in
the relay.
In case of using digital inputs, the user can select the setting table activating these digital inputs (which can come from the
PLC, or from a different relay, or from an auxiliary switch, for adaptive protection). This selection of the active group has
priority over default setting.
The time used in the table change is one PLC logic scan cycle (5 ms typical), allowing a fast adaptation to system changes.
Another type of signal is PROT ACTIVE GROUP, which indicates the active setting group. Protection element settings in the
active group are the values being used by different protection functions.
All actual values signals corresponding to setting groups are located in the
Actual > Status > Control Elements > Setting
Groups menu .
5.4.2 Inverse time curve characteristics
Inverse time curves available in time overcurrent elements are as follows:
IEEE extremely/very/moderately inverse
IEC Curve A/B/C/Long-Time Inverse/ Short-Time Inverse
IAC extremely/very/normally/moderately inverse
ANSI extremely/very/normally/moderately inverse
I2t
Definite time curves
Rectifier time curves
User Curve - FlexCurve A/B/C/D
Recloser Curves
The saturation level for the user curve is 20 times the pickup value, for the rest of time overcurrent elements the
saturation level is 48 times the pickup.
All these curves follow the standards defined for each of them, allowing an efficient coordination with other devices
located downstream. A dial or curve setting allows selection of a tripping time X times the set time in the selected curve.
Fixing this value to 0 would produce an instantaneous response for any selected curve.
Tripping time calculations are performed on the base of an internal variable called “energy”. This energy represents the
system dissipation capability, that is, when 100% of energy is reached, this means that the tripping time associated with
the curve for a certain current value has expired.
Therefore, once the current value has exceeded the pickup value, the relay starts increasing the energy variable value. If it
reaches 100%, a trip is produced. When the current value falls below 97% of the pickup value, the element is reset. There
are two reset types: Instantaneous and Timed (IEEE) or Linear.