10-14 9440300990
Protection DECS-250
Figure 10-16. Sync-Check Protection Settings
Generator Frequency Less Than 10 Hertz
A Generator Below 10 Hz condition is annunciated when the generator frequency decreases below 10 Hz
or when residual voltage is low at 50/60 Hz. A Generator Below 10 Hz annunciation is automatically reset
when the generator frequency increases above 10 Hz or the residual voltage increases above the
threshold.
Configurable Protection
BESTCOMSPlus Navigation Path: Settings Explorer, Protection, Configurable Protection
HMI Navigation Path: Settings, Protection, Configurable Protection
The DECS-250 has eight configurable protection elements which can be used to supplement the
standard DECS-250 protection. BESTCOMSPlus configurable protection settings are illustrated in Figure
10-17. To make the protection elements easier to identify, each element can be given a user-assigned
name. A protection element is configured by selecting the parameter to be monitored and then
establishing the operating characteristics for the element. Any one of the following parameters may be
selected.
• Analog Input 1, 2, 3, 4, 5, 6, 7, 8
• APC Output
• Auxiliary Input Current (mA)
• Auxiliary Input Voltage
• Bus Frequency
• Bus Voltage: V
AB
, V
BC
, or V
CA
• EDM Ripple
• Exciter Field Current
• Exciter Field Voltage
• Gen Current: I
A
, I
B
, I
C
, or Average
• Gen Frequency
• Gen Power Factor
• Gen Voltage: V
AB
, V
BC
, V
CA
, or Average
• Kilovarhours
• Kilowatthours
• LVRT Output
• Negative Sequence Current
• Negative Sequence Voltage
• NLS Error Percent