Internal Status - GE DFF1000 Series Instructions Manual

2.2 INTERNAL STATUS

The DFF is a microprocessor based relay that samples analog inputs, processes them by means of internal
algorithms and activates outputs accordingly. Most of the relay information may be accessed by the user in order
to create specific configurations for each application. With all this information the end-user can configure outputs,
inputs, LEDs and define alarms. All the programmable logic is based on AND, OR and NOT gates.
The DFF presents all this information as "Internal Status". This is nothing but logical Boolean states of all the
internal variables available inside the relay. Each variable may be a "0" or a "1". As an example, one internal state
is the pickup of a frequency unit. If this unit operates as underfrequency, its internal state will be "1". This value
can be addressed to an output contact, an alarm or a LED.
By the same procedure if one digital input is activated, its "internal state" goes to "1", and it can be addressed also
to an output contact, to an alarm or to a LED.
Programmable AND, OR and NOT logic can be done through the internal states information. For example,
activating one output when there is a pickup condition plus a digital input activation.
By adequate use of this "internal states" logic all kind of sophisticated load shedding schemes may be
implemented.
The DFF device has two different types of internal states:
• Protection internal states.
• General and communication internal states.
All those available communication internal states are shown in the following table:
Internal States
0 Mode: Remote (1)
Local (0)
1 Rear Connection
2 Front Connection
3
4
5
6
7
8
9
10
11
12
13
14
15
16 Time/date alarm
17
18 Serial EEPROM
alarm
19 System Settings
GEK – 106166B
TABLE I. COMMUNICATIONS INTERNAL STATES
Internal
States
20
21
22
23
24 Protection
link
25 Control
link
26
27
28
29
30
31
32 New
events
33
34
35
36
37
38
39
Internal States
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
10
Internal
States
60
61
62
63
64 LED 1
65 LED 2
66 LED 3
67 LED 4
68 LED 5
69 LED 6
70 LED 7
71 LED 8
72 LED 9
73 LED 10
74 LED 11
75 LED 12
76 LED 13
77 LED 14
78 LED 15
79 LED 16