Protection Functions; Thermal Overload Protection Mpttr - ABB Relion 630 Series Applications Manual

1MRS756785 A
3.2.6
3.2.6.1
REM630
Application Manual
SCILO function checks for these conditions and provides a closing and opening
enable signal. The enable signal is used by GNRLCSWI function blocks which
check for the operator place selector before providing the final open or close signal
to DAXSWI function.
The open, closed and undefined states of the earth switch are indicated on the
LHMI.
GUID-02640926-724F-4CFA-B189-F643DA17300B V1 EN
Figure 9: Apparatus control

Protection functions

Thermal overload protection MPTTR

The three-phase thermal overload protection function is designed to be used for
protecting electric motors from overheating. The function calculates the thermal
level on the basis of the measured motor load current, rated motor current, and
calculated negative sequence current.
When the thermal level of the motor exceeds a predefined limit, the function
generates a thermal overload alarm. If the thermal content continues to rise and
Section 3
REM630 variants
29