PLC module card PFSK113 7625013-S

PLC module card PFSK113 7625013-S

PLC module card PFSK113 7625013-S

Operation: The operation of the high impedance differential function can be switched On or Off. U>Alarm: Set the alarm level. The sensitivity can roughly be calculated as a certain percentage of the selected Trip level. A typical setting is 10% of U>Trip This alarm stage can be used for scheme CT supervision. tAlarm: Set the time delay for the alarm.

A typical setting is 2-3 seconds. U>Trip: Set the trip level according to the calculations (see examples below for a guidance). The level is selected with margin to the calculated required voltage to achieve stability. Values can be within 20V – 400V range dependent on the application. SeriesResistor: Set the value of the used stabilizing series resistor. Calculate the value according to the examples for each application. Adjust the resistor as close as possible to the calculated value. Measure the value achieved and set this value for this parameter.

T-feeder protection In many busbar arrangements such as one-and a half breaker, ring breaker, mesh corner, there will be a T-feeder from the current transformer at the breakers up to the current transformers in the feeder circuit (for example, in the transformer bushings). It is often required to separate the protection zones that the feeder is protected with one scheme while the T-zone is protected with a separate differential protection scheme. The 1Ph high impedance differential HZPDIF function in the IED allows this to be done efficiently, see Figure 36.