Signals - ABB RELION 611 Series Technical Manual

1MRS757454 D
4.4.1.6
611 series
Technical Manual
occurs on the wye-connected side of the power transformer, negative sequence current
quantities appear on the delta-connected side of the power transformer.
The most common application for the negative sequence overcurrent protection is
probably rotating machines, where negative sequence current quantities indicate
unbalanced loading conditions (unsymmetrical voltages). Unbalanced loading
normally causes extensive heating of the machine and can result in severe damages
even over a relatively short time period.
Multiple time curves and time multiplier settings are also available for coordinating
with other devices in the system.

Signals

Table 233: NSPTOC Input signals
Name Type
I SIGNAL
2
BLOCK BOOLEAN
ENA_MULT BOOLEAN
Table 234: NSPTOC Output signals
Name Type
OPERATE BOOLEAN
START BOOLEAN
Protection functions
Default Description
0 Negative phase sequence current
0=False Block signal for activating the blocking mode
0=False Enable signal for current multiplier
Description
Operate
Start
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