ABB RELION REX640 Technical Manual page 423

1MRS759142 C
REX640
Technical Manual
Table 477: Operation modes
Operation mode
Phase angle
IoSin
IoCos
Phase angle 80
Phase angle 88
Polarizing quantity selection "Neg. seq. volt." is available only in the
"Phase angle" operation mode.
The directional operation can be selected with the Directional mode setting. The
alternatives are "Non-directional", "Forward" and "Reverse" operation. The operation
criterion is selected with the Operation mode setting. By setting Allow Non Dir to
"True", non-directional operation is allowed when the directional information is
invalid, that is, when the magnitude of the polarizing quantity is less than the value of
the Min operate voltage setting.
Typically, the network rotating direction is counter-clockwise and defined as "ABC".
If the network rotating direction is reversed, meaning clockwise, that is, "ACB", the
equation for calculating the negative sequence voltage component need to be changed.
The network rotating direction is defined with a system parameter Phase rotation. The
calculation of the component is affected but the angle difference calculation remains
the same. When the residual voltage is used as the polarizing method, the network
rotating direction change has no effect on the direction calculation.
The network rotating direction is set in the protection relay using the
parameter in the HMI menu: Configuration/System/Phase rotation.
The default parameter value is "ABC".
If the Enable voltage limit setting is set to "True", the magnitude of the
polarizing quantity is checked even if Directional mode is set to "Non-
directional" or Allow Non Dir to "True".
The Characteristic angle setting is used in the "Phase angle" mode to adjust the
operation according to the method of neutral point earthing so that in an isolated
network the Characteristic angle (φ
Protection functions
Description
The operating sectors for forward and reverse are
defined with the settings
forward angle , Min reverse angle and Max reverse
angle .
The operating sectors are defined as "forward"
when |Io| x sin (ANGLE) has a positive value and
"reverse" when the value is negative. ANGLE is
the angle difference between -Uo and Io.
As "IoSin" mode. Only cosine is used for
calculating the operation current.
The sector maximum values are frozen to 80
degrees respectively. Only
Min reverse angle are settable.
The sector maximum values are frozen to 88
degrees. Otherwise as "Phase angle 80" mode.
) = -90° and in a compensated network φ
RCA
Section 4
Min forward angle , Max
Min forward angle and
RCA
417