ABB RELION 620 Series Technical Manual page 775

1MRS757644 F
4.11.3
4.11.4
620 series
Technical Manual
Functionality
The multipurpose protection function MAPGAPC is used as a general protection with
many possible application areas as it has flexible measuring and setting facilities. The
function can be used as an under- or overprotection with a settable absolute hysteresis
limit. The function operates with the definite time (DT) characteristics.
The function contains a blocking functionality. It is possible to block function outputs,
the definite timer or the function itself, if desired.
Operation principle
The function can be enabled and disabled with the Operation setting. The
corresponding parameter values are "On" and "Off".
The operation of MAPGAPC can be described using a module diagram. All the
modules in the diagram are explained in the next sections.
AI_VALUE
Level
detector
ENA_ADD
Blocking
BLOCK
logic
GUID-50AA4A14-7379-43EB-8FA0-6C20C12097AC V1 EN
Figure 394: Functional module diagram
Level detector
The level detector compares AI_VALUE to the Start value setting. The Operation
mode setting defines the direction of the level detector.
Table 730: Operation mode types
Operation Mode
"Under"
"Over"
The Absolute hysteresis setting can be used for preventing unnecessary oscillations if
the input signal is slightly above or below the Start value setting. After leaving the
hysteresis area, the start condition has to be fulfilled again and it is not sufficient for
the signal to only return to the hysteresis area. If the ENA_ADD input is activated, the
threshold value of the internal comparator is the sum of the Start value Add and Start
Protection functions
Timer
OPERATE
t
START
Description
If the input signal AI_VALUE is lower than the set
value of the "Start value" setting, the level detector
enables the timer module.
If the input signal AI_VALUE exceeds the set
value of the Start value setting, the level detector
enables the timer module.
Section 4
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