Sel 411L - Figure 3.221 CT Saturation Plot

P.3.337
Date Code 20151029 Protection Manual SEL-411L Relay
Protection Functions
Protection Application Examples
Figure 3.221 CT Saturation Plot
Apply the typical values for this application.
The following settings apply to Relay R because it is a master and runs the
differential element.
We would have the following at Relay R:
87LPP := 0.5 Pickup 87LP Element (OFF, 0.1–2 pu)
87LPR := 6 Radius 87LP Element (1.2–8)
87LPA := 195 Block Angle 87LP Element (90–270°)
87LQP := 0.25 Pickup 87LQ Element, Sec. Mode (0.1–2 pu)
87LQR := 6 Radius 87LQ Element, Sec. Mode (1.2–8)
87LQA := 195 Block Angle 87LQ Element, Sec. Mode (90–270°)
87LGP := 0.25 Pickup 87LG Element (OFF, 0.1–2 pu)
87LGR := 6 Radius 87LG Element (1.2–8)
87LGA := 195 Block Angle 87LG Element (90–270°)
The relay will automatically switch to secure settings if it cannot apply
charging current compensation. Increase the pickup setting of the phase
differential element to ensure that it will not operate for charging current.
87LPPS := 1.2 Pickup 87LP Element, Sec. Mode (0.1–2 pu)
87LPRS := 7.2 Radius 87LP Element, Sec. Mode (1.2–8)
87LPAS := 234 Block Angle 87LP Element, Sec. Mode (90–270°)
87LQPS := 0.3 Pickup 87LQ Element (OFF, 0.1–2 pu)
87LQRS := 7.2 Radius 87LQ Element (1.2–8)
87LQAS := 234 Block Angle 87LP Element (90–270°)
87LGPS := 0.3 Pickup 87LG Element, Sec. Mode (0.1–2 pu)
87LGRS := 7.2 Radius 87LG Element, Sec. Mode (1.2–8)
87LGAS := 234 Block Angle 87LG Element, Sec. Mode (90–270°)