1-
20
DGP Digital Generator Protection System GE Power Management
1.4 OTHER FEATURES 1 PRODUCT DESCRIPTION
1
Figure 1–8: FREQUENCY-SENSITIVITY CHARACTERISTICS
1.4.8 TIME SYNCHRONIZATION
The DGP system includes a real time clock that can run freely or be synchronized from an external signal. Two
different external time-sync signals are possible. If the DGP is connected to the host computer of a G-NET sub-
station information and control system, then the DGP receives a time-sync pulse via pin 25 of port PL-1. If the
DGP is not connected to a G-NET host computer, then a demodulated IRIG-B signal connected to optional port
PL-3 may be used to synchronize the clock. In both cases, the clock in a given DGP is synchronized to within
±1 millisecond of any other digital relay clock, provided the two relays are wired to the same synchronizing sig-
nal.
Frequency Vs Sensitivity
DGP Relay System
0
1
2
3
4
5
6
7
8
9
10
11
12
0 102030405060708090100
System Frequency
64G1
32
24
46
59
51V
87G
32
46
24
Relative Sensitivity
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