Basler Electric DGC-2020HD - Manual (Page 155)

9469300990 Rev B 145
BESTCOMSPlus Navigation Path: Settings Explorer, Generator Protection, Power, Power (32)
Front Panel Navigation Path: Settings Explorer > Protection > Settings Group x (where x = 0 to 3) >
Power Protection > Power (32)
Element Operation
Power protection can be used in applications where excessive power flow in the tripping direction is
undesired.
Two sets of over/under power settings are provided for each element: one for three-phase generator
connections and one for single-phase generator connections. The Pickup setting entered is based on the
CT secondary side (DGC-2020HD). When a single-phase override contact input is received, the DGC-
2020HD automatically switches from the three-phase power settings to the single-phase power settings.
A 32 element monitors three-phase real power when three-phase sensing is active or single-phase real
power if single-phase sensing is active.
Source
Source settings configure a power element to monitor the generator sensing input terminals or the bus
sensing input terminals.
Direction of Power Flow
In addition to exceeding the threshold established by the Pickup setting, direction of power flow (forward
or reverse) must match the Direction setting for the 32 element to operate. In the DGC-2020HD, the
forward and reverse directions are defined by the polarity voltage and current connections to the
controller as shown in Figure 81. Based on IEEE polarity convention, forward power is defined as bus to
line and reverse power is defined as line to bus.
Figure 81. Direction of Power Flow Defined by the Polarity of Voltage and Current Connections
Over and Under Mode
An Over Under setting configures a power element to trip for an overpower or underpower condition.
Pickup and Trip
When the calculated real power increases above or decreases below the threshold established by the
Pickup setting, a timer begins timing towards a trip.
Timer duration is established by the Activation Delay. An Activation Delay of zero (0) makes the 32
element instantaneous with no intentional time delay.
If power pickup condition persists for the duration of the element Activation Delay setting, the element Trip
output becomes true. In BESTlogicPlus, the Trip output can be connected to other logic elements or a
physical relay output to annunciate the condition and initiate corrective action.
If the pickup condition subsides before the element activation delay expires, the timer is reset, no
corrective action is taken, and the element is rearmed for any other occurrences of over/under power.
DGC-2020HD Generator Protection