5.1.3
Signals and signal management
A function block has set of input and output signals. The placement of the signals for a
function block is from left to right. Input signals are placed on the left side and output
signals are placed on the right side.
A function block can contain more signals than needed in that application part. A
signal that is not used in a particular application is possible to hide in the function
block view in ACT.
Signals are located on both sides of the middle position up and down. When there is
space left, move some signals up or down for a better visibility and connection routing.
Boolean input and output signals may need to be inverted to fulfill the logic. ACT
supports to add the inversion logic to a binary signal.
The input signal on glue logic function blocks can only be inverted if a
glue logic function block with lower execution order in the same cycle
time is available. Similar, the output signal can only be inverted if a
glue logic function block with higher execution order in the same cycle
time is available. Up to two input signals and two output signals can be
inverted for glue logic blocks in the same cycle time.
Even though current is injected to the IED and the IED is connected to
PCM600 in online mode, the signal value in ACT is shown as zero.
All not mandatory input signals have a default value that will be used when not connected.
5.1.4
Function block execution parameters
Three function block execution parameters have influence on the runtime execution of
the function block within the application configuration.
•
Execution order
•
Cycle time
•
Instance number
Each time a new function block is selected these parameters have to be selected. In
fixed mode user selects parameters from the drop down lists in ACT. In automatic
mode best suitable instance is selected automatically. Depending on the function block
type not all three parameters are selectable. The cycle time may be predefined to one
value. The instance number is a counter for the total possible number of function
blocks of that type used within an application configuration.
Section 5
1MRK 511 245-UUS -
Protection and control engineering
56
650 series ANSI
Engineering Manual
