ABB Relion REC615 - Operation Principle

4.7.3 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.
4.7.4 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 OPERATE
Level
detector
Blocking
logic
BLOCK
START
Timer
ENA_ADD
t
Figure 232: 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 502: Operation mode types
Operation Mode Description
"Under"
If the input signal AI_VALUE is lower than
the set value of the "Start value" setting, the
level detector enables the timer module.
"Over"
If the input signal AI_VALUE exceeds the set
value of the Start value setting, the level de-
tector enables the timer module.
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 value settings. The resulting threshold value for the comparator can be
Protection functions
1MRS758755 C
472 REC615 & RER615
Technical Manual