GE C70 Instruction Manual page 249

5 SETTINGS
The equation for virtual output 4 is:
[85] Virt Op 4 On
[86] Virt Op 1 On
[87] Virt Op 2 On
[88] Virt Ip 1 On
[89] DIG ELEM 1 PKP
[90] XOR(2)
[91] Virt Op 3 On
[92] OR(4)
[93] LATCH (S,R)
[94] Virt Op 3 On
[95] TIMER 1
[96] Cont Ip H1c On
[97] OR(3)
[98] TIMER 2
[99] = Virt Op 4
It is now possible to check that the selection of parameters will produce the required logic by converting the set of parame-
ters into a logic diagram. The result of this process is shown below, which is compared to the logic for virtual output 4 dia-
gram as a check.
FLEXLOGIC ENTRY n:
85
Virt Op 4 On
FLEXLOGIC ENTRY n:
86
Virt Op 1 On
FLEXLOGIC ENTRY n:
87
Virt Op 2 On
FLEXLOGIC ENTRY n:
88
Virt Ip 1 On
FLEXLOGIC ENTRY n:
89
DIG ELEM 1 PKP
FLEXLOGIC ENTRY n:
90
XOR
FLEXLOGIC ENTRY n:
91
Virt Op 3 On
FLEXLOGIC ENTRY n:
92
OR (4)
FLEXLOGIC ENTRY n:
93
LATCH (S,R)
FLEXLOGIC ENTRY n:
94
Virt Op 3 On
FLEXLOGIC ENTRY n:
95
TIMER 1
FLEXLOGIC ENTRY n:
96
Cont Ip H1c On
FLEXLOGIC ENTRY n:
97
OR (3)
FLEXLOGIC ENTRY n:
98
TIMER 2
FLEXLOGIC ENTRY n:
99
=Virt Op 4
Figure 5–47: FLEXLOGIC EQUATION FOR VIRTUAL OUTPUT 4
7. Now write the complete FlexLogic expression required to implement the logic, making an effort to assemble the equa-
tion in an order where Virtual Outputs that will be used as inputs to operators are created before needed. In cases
where a lot of processing is required to perform logic, this may be difficult to achieve, but in most cases will not cause
problems as all logic is calculated at least four times per power frequency cycle. The possibility of a problem caused by
sequential processing emphasizes the necessity to test the performance of FlexLogic before it is placed in service.
In the following equation, virtual output 3 is used as an input to both latch 1 and timer 1 as arranged in the order shown
below:
DIG ELEM 2 OP
Cont Ip H1c On
NOT
AND(2)
GE Multilin
XOR OR
T1
C70 Capacitor Bank Protection and Control System
Set
LATCH
Reset
T2
OR
5.5 FLEXLOGIC
5
VIRTUAL
OUTPUT 4
827031A2.VSD
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