ABB Relion REC670 - Page 162

The function has two stages that can be set independently.
With the parameter OpMode1(2) the function can be set On / Off .
The function gives trip if the power component in the direction defined by the setting
Angle1(2) is smaller than the set pick up power value Power1(2)
Operate
Angle1(2)
Power1(2)
P
Q
en06000441.vsd
IEC06000441 V1 EN-US
Figure 71: Underpower mode
The setting Power1(2) gives the power component pick up value in the Angle1(2) direction. The
setting is given in p.u. of the generator rated power, see equation
73.
Minimum recommended setting is 0.2% of S
N
when metering class CT inputs into the IED are
used.
3
N
S UBase IBase= × ×
EQUATION1708 V1 EN-US
(Equation 73)
The setting Angle1(2) gives the characteristic angle giving maximum sensitivity of the power
protection function. The setting is given in degrees. For active power the set angle should be
0° or 180°. 0° should be used for generator low forward active power protection.
Section 7 1MRK 511 358-UEN A
Current protection
156
Application manual