ABB Relion 611 Series, Technical Manual

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The start-up current is specific to each motor and depends on the start-up method used,
such as direct online, autotransformer and rotor resistance insertion. The start-up time
is dependent on the load connected to the motor.
Based on the motor characteristics supplied by the manufacturer, this module is
required if the stalling time is shorter than or too close to the starting time. In such
cases, a speed switch must be used to indicate whether a motor is accelerating during
start-up or not.
At motor standstill, the
STALL_IND
input is active. It indicates that the rotor is not
rotating. When the motor is started, at certain revolution the deactivation of the
STALL_IND
by the speed switch indicates that the rotor is rotating. If the input is not
deactivated within Lock rotor time , the
OPR_STALL
output is activated.
The module calculates the duration of the motor in stalling condition, the
STALL_RL
output indicating the percent ratio of the start situation and the set value of Lock rotor
time . The value is available in the Monitored data view.
The activation of the
BLOCK
input signal resets the operation time and deactivates the
OPR_STALL
output.
Cumulative start-up protection
This module protects the motor from an excessive number of start-ups.
Whenever the motor is started, the latest value of
START_TIME
is added to the
existing value of
T_ST_CNT
and the updated cumulative start-up time is available at
T_ST_CNT
. If the value of
T_ST_CNT
is greater than the value of Cumulative time
Lim , the
LOCK_START
output is activated and lockout condition for the restart of
motor is enabled during the time the output is active. The
LOCK_START
output
remains high until the
T_ST_CNT
value reduces to a value less than the value of
Cumulative time Lim . The start time counter reduces at the rate of the value of Counter
Red rate .
The
LOCK_START
output becomes activated at the start of
MOT_START
. The output
remains active for a period of Restart inhibit time .
Section 4
1MRS757454 D
Protection functions
294 611 series
Technical Manual