9440300990 Rev J
53
DECS-250
Protection
elements in BESTlogic
Plus
can be used in a logic scheme to initiate corrective action in response to the
condition. BESTCOMS
Plus
power input failure settings are illustrated in Figure 39.
Figure 39. Power Input Failure Protection Settings
A
Time Delay (s)
: Adjustable from 0 to 10 seconds in 0.1 second increments.
B
Mode
: Select Disabled or Enabled.
C
Power Input Configuration:
Read-only value
Sync-Check Protection
BESTCOMSPlus Navigation Path:
Settings Explorer, Protection, Sync Check (25)
HMI Navigation Path:
Settings, Protection, Sync Check (25)
Caution
Because the DECS-250 sync-check and automatic synchronizer
functions share internal circuitry, the sync-check function is not
available when the automatic synchronizer style option is selected.
When enabled
A
, the sync-check (25) function supervises the automatic or manual synchronism of the
controlled generator with a bus/utility. During synchronizing, the 25 function compares the voltage
B
, slip
angle
C
, and slip frequency
D
differences between the generator and bus. When the generator/bus
differences fall within the setting for each parameter, the 25 status virtual output asserts. This virtual
output can be configured (in BESTlogic
Plus
)
to assert a DECS-250 contact output. This contact output
can, in turn, enable the closure of a breaker tying the generator to the bus.
An angle compensation
E
setting is provided to offset phase shift caused by transformers in the system.
For more details on the angle compensation setting, see the
Synchronizer
chapter.
When the Gen Freq > Bus Freq
F
setting box is checked, the 25 status virtual output will not assert unless
the generator frequency is greater than the bus frequency. Sync-check protection settings are illustrated
in Figure 40.
Summary of Contents for DECS-250
Page 2: ......
Page 6: ...iv 9440300990 Rev J Revision History DECS 250 ...
Page 16: ...xiv 9440300990 Rev J Contents DECS 250 ...
Page 20: ...4 9440300990 Rev J Introduction DECS 250 ...
Page 28: ...12 9440300990 Rev J Power Stage DECS 250 ...
Page 32: ...16 9440300990 Rev J Voltage and Current Sensing DECS 250 ...
Page 40: ...24 9440300990 Rev J Synchronizer DECS 250 ...
Page 52: ...36 9440300990 Rev J Auxiliary Control DECS 250 ...
Page 56: ...40 9440300990 Rev J Contact Inputs and Outputs DECS 250 ...
Page 84: ...68 9440300990 Rev J Limiters DECS 250 ...
Page 114: ...98 9440300990 Rev J Power System Stabilizer DECS 250 Figure 96 PSS Parameter Settings ...
Page 124: ...108 9440300990 Rev J Stability Tuning DECS 250 ...
Page 126: ...110 9440300990 Rev J Mounting DECS 250 Figure 103 Overall and Projection Mounting Dimensions ...
Page 127: ...9440300990 Rev J 111 DECS 250 Mounting Figure 104 DECS 250 Escutcheon Plate Dimensions ...
Page 198: ...182 9440300990 Rev J Timekeeping DECS 250 ...
Page 210: ...194 9440300990 Rev J CAN Communication DECS 250 ...
Page 304: ...288 9440300990 Rev J Maintenance DECS 250 ...
Page 316: ...300 9440300990 Rev J Specifications DECS 250 ...
Page 334: ...318 9440300990 Rev J Analog Expansion Module DECS 250 ...
Page 351: ......