GE Industrial Solutions Entellisys System User Manual - Manual (Page 163)

FlexLogic example 163
11
Figure 11-5 FlexLogic worksheet
a. Following the procedure outlined, start with parameter 99, as follows:
99: The final output of the equation is Virtual Output 3, which is created by the operator
“= Virt Op n”. This parameter is therefore “= Virt Op 3”.
98: The gate preceding the output is an AND, which in this case requires two inputs. The
operator for this gate is a 2-input AND so the parameter is “AND (2)”.
NOTE: FlexLogic rules require that the number of inputs to most types of operators must be
specified to identify the operands for the gate. As the 2-input AND will operate on the two
operands preceding it, these inputs must be specified, starting with the lower.
97: This lower input to the AND gate must be passed through an inverter (the NOT
operator) so the next parameter is “NOT”. The NOT operator acts upon the operand
immediately preceding it, so specify the inverter input next.
96: The input to the NOT gate is to be contact input H1c. The operand is therefore “Cont Ip
H1c On”.
95: The last step in the procedure is to specify the upper input to the AND gate, the
operated state of digital element 2. This operand is “DIG ELEM 2 OP”.
b. Write the parameters in numerical order to now form the equation for VIRTUAL
OUTPUT 3:
[95] DIG ELEM 2 OP
[96] Cont Ip H1c On
[97] NOT
[98] AND (2)
[99] = Virt Op 3
c. It is now possible to check that this selection of parameters will produce the required
logic by converting the set of parameters into a logic diagram. The result of this process
is shown in Figure 11-6, which can be compared to the “Logic for Virtual Output 3”
diagram (Figure 11-3) as a check.