ABB Relion, Technical Manual

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FNKEYMD1 - FNKEYMD5 function block also has a number of settings and parameters
that control the behavior of the function block. These settings and parameters are normally
set using the PST.
Operating sequence
The operation mode is set individually for each output, either OFF , TOGGLE or
PULSED .
Setting OFF
This mode always gives the output the value. A change of the input value does not affect
the output value.
Input value
Output value
IEC09000330-1-en.vsd
IEC09000330 V1 EN
Figure 26: Sequence diagram for setting OFF
Setting TOGGLE
In this mode the output toggles each time the function block detects that the input has been
written (the input has completed a pulse). Note that the input attribute is reset each time the
function block executes. The function block execution is marked with a dotted line below.
Input value
Output value
IEC09000331_1_en.vsd
IEC09000331 V1 EN
Figure 27: Sequence diagram for setting TOGGLE
Setting PULSED
In this mode the output will be high for as long as the setting pulse time . After this time the
output will go back to 0. The input attribute is reset when the function block detects it
being high and there is no output pulse.
Note that the third positive edge on the input attribute does not cause a pulse, since the
edge was applied during pulse output. A new pulse can only begin when the output is zero;
else the trigger edge is lost.
1MRK 502 048-UUS A
Section 5
Local Human-Machine-Interface LHMI
83
Technical manual