ABB Relion REC615, Техническое руководство

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increased or decreased depending on the sign and value of the
Start value Add
setting.
Timer
Once activated, the timer activates the
START
output. The time characteristic is
according to DT. When the operation timer has reached the value set by
Operate
delay time, the
OPERATE
output is activated. If the starting condition disappears
before the module operates, the reset timer is activated. If the reset timer reaches
the value set by
Reset delay time, the operation timer resets and the
START
output
is deactivated.
The timer calculates the start duration value START_DUR, which indicates the
percentage ratio of the start situation and the set operation time. The value is
available in the monitored data view.
Blocking logic
There are three operation modes in the blocking function. The operation modes
are controlled by the
BLOCK
input and the global setting in Configuration >
System > Blocking mode which selects the blocking mode. The
BLOCK
input can
be controlled by a binary input, a horizontal communication input or an internal
signal of the protection relay's program. The influence of the
BLOCK
signal activation
is preselected with the global setting
Blocking mode.
The
Blocking mode setting has three blocking methods. In the "Freeze timers"
mode, the operation timer is frozen to the prevailing value, but the
OPERATE
output
is not deactivated when blocking is activated. In the "Block all" mode, the whole
function is blocked and the timers are reset. In the "Block OPERATE output" mode,
the function operates normally but the
OPERATE
output is not activated.
4.7.5 Application
The function block can be used for any general analog signal protection, either
underprotection or overprotection. The setting range is wide, allowing various
protection schemes for the function. Thus, the absolute hysteresis can be set to
a value that suits the application.
The temperature protection using the RTD sensors can be done using the function
block. The measured temperature can be fed from the RTD sensor to the function
input that detects too high temperatures in the motor bearings or windings, for
example. When the
ENA_ADD
input is enabled, the threshold value of the internal
comparator is the sum of the Start value Add and Start value settings. This allows a
temporal increase or decrease of the level detector depending on the sign and value
of the Start value Add setting, for example, when the emergency start is activated.
If, for example, Start value is 100, Start value Add is 20 and the
ENA_ADD
input is
active, the input signal needs to rise above 120 before MAPGAPC operates.
1MRS758755 C Protection functions
REC615 & RER615
Technical Manual
473