Woodward HighPROTEC - Directional Features for Calculated (IG Calc) Ground Fault 50 N;51 N

Module: Protection (Prot)
Directional Features for Calculated (IG calc) Ground Fault 50N/51N
All ground fault elements can be selected as » non-directional/forward/reverse« operated. This has to be done in
the » Device Planning« menu.
Important Definitions
Polarizing Quantity: This is the quantity that is used as a reference value. The polarizing quantity can be selected
by the parameter » IG calc dir ctrl« in the [Field Para/Direction] menu as follows:
»IG calc 3V0« : The neutral voltage selected by the parameter » 3V0 Source« will be used
as the polarizing quantity. The traditional way to polarize a ground fault element is to use
neutral voltage (3V0). The neutral voltage can, however, be either » measured« or
» calculated« . This can be selected by the parameter » 3V0 Source« in the [Field
Para/Direction] menu.
»IG calc Ipol (IG meas)« : The measured neutral current (usually = IG meas) will be used
as polarizing quantity.
»Dual« : For this method, the measured neutral current Ipol=IG meas will be used as
polarizing quantity, if available, otherwise 3V0 will be used.
»I2,V2« : With this selection, the negative phase sequence voltage and current will be used
to detect the direction. The monitored current is still the calculated residual current IG
calc.
Operating Quantity: For the directional IG calc elements, the operating quantity is in general the calculated neutral
current IG calc ( except from » I2,V2« mode, where » I2« is the operating quantity).
The ground maximum torque angles (MTA) can be adjusted from 0° to 360°, except, if » IG calc Ipol (IG meas)« is
selected. In this case it is set to 0° (fixed).
The MTA will also be set internally to 0° in case that Ipol=IG meas is available within the Dual-Mode
522 MCDGV4 DOK-HB-MCDGV4-2E