GE DGP Series - Undervoltage Cutoff of 81; Underfrequency 81-U; Overfrequency 81-O; Digital Input DI

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DGP Digital Generator Protection System GE Power Management
2.3 PROTECTION FUNCTION SETTINGS 2 CALCULATION OF SETTINGS
2
2.3.14 UNDERVOLTAGE CUTOFF OF 81
Setting 1601:
UVCUTOFF
can be set from 35 to 99% of the nominal voltage (Setting 114:
NOM VOLT
). This
setting can be used to block the frequency functions from operating during start-up conditions until near-normal
generator field is applied and set voltage is generated.
2.3.15 UNDERFREQUENCY 81-U
There are either two or four underfrequency functions included with the DGP, depending on the model. Each of
the functions (Settings 1703/1803/1903/2003:
SET PNT
) can be set from 40.00 to 65.00 Hz, with a time delay
of 0.1 to 999.9 seconds for 81-1U and 0.05 to 99.99 seconds for the other(s). The actual settings will depend
on the protection and operating philosophies of the individual user.
2.3.16 OVERFREQUENCY 81-O
There are either two or four overfrequency functions included in the DGP, depending on the model. Each of the
functions (Settings 2103/2203/2303/2403:
SET PNT
) can be set from 45.00 to 79.99 Hz, with a time delay of
0.05 to 99.99 seconds. The actual settings will depend on the protection and operating philosophies of the indi-
vidual user.
2.3.17 DIGITAL INPUT DI
Setting 2501:
SELBKDI1
determines the blocking action by digital input DI1 (generator off-line) when it is ener-
gized. It is set from 0 to 9 depending on the protection functions to be blocked during the start-up. The table
below describes the different blocking actions:
Note that for DGP***ABA models, some of the
SELBKDI1
settings are functionally redundant; any one of such
settings may be used to obtain the specified functionality.
Table 2–4: DI1 BLOCKING CONFIGURATION
SELBKDI1 FUNCTIONS DISABLED (X) BY DI1
81 32
64G2 / 27TN
1
VTFF
NO BLK (0) - - - -
BLK #1 (1)
X
--
X
BLK #2 (2)
X
-
X
-
BLK #3 (3)
X
-
XX
BLK #4 (4)
XX
--
BLK #5 (5) -
X
-
X
BLK #6 (6)
XX
-
X
BLK #7 (7) -
XXX
BLK #8 (8)
X
---
BLK #9 (9)
XX X X
1
Refer to the Nomenclature Guide for available functions