Basler Electric DGC-2020 - Manual (Page 185)

Figure 4-62 Mains Fail
A Mains Fail Transfer: Enable or Disable. This setting does not apply when generator frequency is 400Hz.
B Mains Fail Transfer Delay: Adjustable from 0 to 300 s in 1 s increments. This specifies the delay
between detection of failed mains to initiation of the transfer to the generator.
C Mains Fail Return Delay: Adjustable from 0 to 1,800 s in 1 s increments. This specifies the delay
between detection of restored (stable) mains and initiation of the return from the generator back to the
mains.
D Mains Fail Max Transfer Time: Adjustable from 10 to 3,700 s in 1 s increments. This specifies the
maximum time that is allowed for a transfer from failed mains to generator power. If the transfer has not
been achieved in this time, a Mains Fail Transfer Fail pre-alarm is annunciated and the transfer is
aborted. The pre-alarm can be cleared by switching to OFF mode or pressing the Reset button on the
front panel of the DGC-2020. Note that the Mains Fail Max Transfer Time setting must be longer than
the time for the Mains Fail Transfer Delay plus the Sync Activation Delay plus the Breaker Close Wait
Time.
E Mains Fail Max Return Time: Adjustable from 10 to 3,700 s in 1 s increments. This specifies the
maximum time that is allowed for a transfer from generator power to mains power when returning to
mains after a mains fail transfer to generators has occurred. This must be set to a time interval longer
than the Max Parallel Time when closed transitions are employed. In addition, it must be set longer than
the time for the generator to ramp down from full load to no load when transferring to utility. If this timer
times out when the DGC-2020 is attempting to transfer from generator power to mains power after mains
returns, a Mains Fail Return Fail pre-alarm will be annunciated. The DGC-2020 will continue to attempt to
return to mains even though the pre-alarm has been annunciated.
F Mains Fail Transfer Type: Closed or Open.
G Mains Breaker Open Configuration: Generator Start or Generator Stable.
H In-Phase Monitor: Disable or Enable.
I Open Transition Delay: Adjustable from 0 to 3,600 in 0.1 s increments.
J Max Parallel Time: Adjustable from 0.1 to 10,000 s in 0.1 s increments.
K Alarm State Transfer to Mains: Disable or Enable.
L Reverse Rotation Inhibit: Disable or Enable.
Bus Condition Detection
Bus condition detection settings are provided for generator sensing and bus sensing.
Generator Sensing
DGC-2020 detection of dead generator voltages is controlled by a Dead Gen Threshold setting A and a
Dead Gen Activation Delay setting B . A dead generator is recognized when the voltage of all phases
decreases below the threshold setting for the duration of the time delay setting. Normally, it is not possible
to close the generator breaker when the generator is dead. However, in cases where it is required to
connect a generator that is “dead” to a bus that is “dead” for purposes of startup synchronization, both the
generator and the bus must be recognized as “dead”. To permit a close of the generator breaker from a
“dead” generator to a “dead” bus, both the Dead Bus Close Enable setting and the Dead Gen Close
Enable setting, in Breaker Hardware settings, must be set to enabled.
9400200990 Rev X DGC-2020 BESTCOMSPlus
® Software
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