ABB RELION Series, Technical Manual

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3.16.16.2 Functionality
The multipurpose generic up-down counter function UDFCNT counts up or down for
each positive edge of the corresponding inputs. The counter value output can be reset
to zero or preset to some other value if required.
The function provides up-count and down-count status outputs, which specify the
relation of the counter value to a loaded preset value and to zero respectively.
3.16.16.3 Operation principle
The function can be enabled and disabled with the Operation setting. The
corresponding parameter values are "On" and "Off".
The operation of UDFCNT can be described with a module diagram. All the modules
in the diagram are explained in the next sections.
GUID-9D9880AB-4CA7-4DD5-BA0C-C1D958FC04F6 V1 EN
Figure 108: Functional module diagram
Up-down counter
Each rising edge of the
UP_CNT
input increments the counter value
CNT_VAL
by one
and each rising edge of the
DOWN_CNT
input decrements the
CNT_VAL
by one. If
there is a rising edge at both the inputs UP_CNT and DOWN_CNT , the counter value
CNT_VAL
is unchanged. The
CNT_VAL
is available in the monitored data view.
The counter value
CNT_VAL
is stored in a nonvolatile memory. The range of the
counter is 0...+2147483647. The count of
CNT_VAL
saturates at the final value of
2147483647, that is, no further increment is possible.
The value of the setting Counter load value is loaded into counter value
CNT_VAL
either when the
LOAD
input is set to "True" or when the Load Counter is set to "Load"
in the LHMI. Until the
LOAD
input is "True", it prevents all further counting.
The function also provides status outputs
UPCNT_STS
and
DNCNT_STS
. The
UPCNT_STS
is set to "True" when the
CNT_VAL
is greater than or equal to the setting
Counter load value .
DNCNT_STS
is set to "True" when the
CNT_VAL
is zero.
The
RESET
input is used for resetting the function. When this input is set to "True" or
when Reset counter is set to "reset", the
CNT_VAL
is forced to zero.
1MRS758755 A
Section 3
Basic functions
REC615 and RER615 177
Technical Manual