Basler Electric DGC-2020HD - Manual (Page 157)

9469300990 Rev B 147
Figure 83. Settings Explorer, Generator Protection, Power
Loss of Excitation (40Q)
Two loss of excitation protection (40Q) elements monitor three-phase or single-phase reactive power
(vars).
The two, identical loss of excitation protection elements are designated 40Q-1 and 40Q-2. Element logic
connections are made on the BESTlogicPlus screen in BESTCOMSPlus and element operational settings
are configured on the Loss of Excitation screen in BESTCOMSPlus.
BESTCOMSPlus Navigation Path: Settings Explorer, Generator Protection, Power, Loss of Excitation
(40Q)
Front Panel Navigation Path: Settings Explorer > Protection > Settings Group x (where x = 0 to 3) >
Power Protection > Loss of Excitation (40Q)
Element Operation
Two sets of loss of excitation settings are provided: one for three-phase generator connections and one
for single-phase generator connections. The Pickup setting entered is based on the percentage of the
machine Rated kvar on the Rated Data screen. When a single-phase override contact input is received,
the DGC-2020HD automatically switches from the three-phase loss of excitation settings to the single-
phase loss of excitation settings. A 40Q element monitors three-phase reactive power when three-phase
sensing is active or single-phase reactive power if single-phase sensing is active.
Source
Source settings configure a loss of excitation element to monitor the generator sensing input terminals or
the bus sensing input terminals.
DGC-2020HD Generator Protection