ABB Relion 611 Series, Technical Manual

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mechanism or harm the personnel handling the machine. Therefore, the motor has to
be disconnected from the power supply as soon as the above condition is detected.
LOFLPTUC detects the condition by monitoring the current values and helps
disconnect the motor from the power supply instantaneously or after a delay according
to the requirement.
When the motor is at standstill, the current will be zero and it is not recommended to
activate the trip during this time. The minimum current drawn by the motor when it is
connected to the power supply is the no load current, that is, the higher start value
current. If the current drawn is below the lower start value current, the motor is
disconnected from the power supply. LOFLPTUC detects this condition and
interprets that the motor is de-energized and disables the function to prevent
unnecessary trip events.
4.1.5.6 Signals
Table 134: LOFLPTUC Input signals
Name Type Default Description
I_A SIGNAL 0 Phase A current
I_B SIGNAL 0 Phase B current
I_C SIGNAL 0 Phase C current
BLOCK BOOLEAN 0=False Block all binary outputs by resetting timers
Table 135: LOFLPTUC Output signals
Name Type Description
OPERATE BOOLEAN Operate
START BOOLEAN Start
4.1.5.7 Settings
Table 136: LOFLPTUC Group settings (Basic)
Parameter Values (Range) Unit Step Default Description
Start value low 0.01...0.50 xIn 0.01 0.10 Current setting/Start value low
Start value high 0.01...1.00 xIn 0.01 0.50 Current setting/Start value high
Operate delay time 400...600000 ms 10 2000 Operate delay time
Table 137: LOFLPTUC Non group settings (Basic)
Parameter Values (Range) Unit Step Default Description
Operation 1=on
5=off
1=on Operation Off / On
1MRS757454 D
Section 4
Protection functions
611 series 143
Technical Manual