ABB RELION 620 Series Technical Manual page 773

1MAC504801-IB E
9.4.4
620 series ANSI
Technical Manual
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.
Operation principle
The function can be enabled and disabled with the Operation setting. The corresponding
parameter values are "Enable" and "Disable".
The operation of the multipurpose generic up-down counter 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 393: 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.
Section 9
Control functions
767