GE TRANSFORMER MANAGEMENT RELAY 745 Instruction Manual page 139

5 SETPOINTS
Table 5–13: FLEXLOGIC™ GATES
GATES NUMBER OF INPUTS
NOT 1
OR 2 to 19 (for 20 parameter equations)
2 to 9 (for 10 parameter equations)
AND 2 to 19 (for 20 parameter equations)
2 to 9 (for 10 parameter equations)
NOR 2 to 19 (for 20 parameter equations)
2 to 9 (for 10 parameter equations)
NAND 2 to 19 (for 20 parameter equations)
2 to 9 (for 10 parameter equations)
XOR 2 to 19 (for 20 parameter equations)
2 to 9 (for 10 parameter equations)
Inputs and gates are combined into a FlexLogic™ equation. The sequence of entries in the linear array of parameters fol-
lows the general rules listed in the following section.
1. INPUTS TO A GATE ALWAYS PRECEDE THE GATE IN THE EQUATION.
2. GATES HAVE ONLY ONE OUTPUT.
3. THE OUTPUT OF A GATE CAN BE THE INPUT TO ANOTHER GATE. Therefore, according to rule 1, the former gate
will precede the latter gate in the equation.)
4. ANY INPUT CAN BE USED MORE THAN ONCE IN AN EQUATION.
5. THE OUTPUT OF AN EQUATION CAN BE USED AS AN INPUT TO ANY EQUATION (INCLUDING FEEDBACK TO
ITSELF).
6. IF ALL PARAMETERS OF AN EQUATION ARE NOT USED, THE 'END' PARAMETER MUST FOLLOW THE LAST
PARAMETER USED.
As an example, assume that the following logic is required to operate Output Relay 2:
Based on the rules given above, the Output Relay 2 FlexLogic™ equation is shown above. On the left is a stack of boxes
showing the FlexLogic™ messages for Output Relay 2. On the right of the stack of boxes is an illustration of how the equa-
tion is interpreted.
In this example, the inputs of the 4-input OR gate are Percent Diff OP, Inst Diff OP, the output of the XOR gate, and the out-
put of the AND gate. The inputs of the 2-input AND gate are the output of the NOT gate, and Output Relay 2. The input to
the NOT gate is Logic Input 2. The inputs to the 2-input XOR gate are Virtual Output 1 and Logic Input 1. For all these
gates, the inputs precede the gate itself.
GE Multilin
Courtesy of NationalSwitchgear.com
OUPUT IS "1" (= ON) IF...
input is '0'
any input is '1'
all inputs are '1'
all inputs are '0'
any input is '0'
odd number of inputs are '1'
Percent Diff
OPERATE
Inst Diff
OPERATE
Virtual Output 1
OPERATE
XOR
Logic Input 1
ASSERTED
Logic Input 2
ASSERTED
AND
Figure 5–43: FLEXLOGIC™ EXAMPLE
745 Transformer Management Relay
5.7.3 FLEXLOGIC™ RULES
Output Relay 2
OR
OPERATE
5.7 S5 OUTPUTS
5
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