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Note:
Uuf: Voltage imbalance degree
Us1: Alarm action threshold
Us2: Trip action threshold
Ts1: Delay time of alarm action
Ts2: Delay time of trip action
6.13 Phase fail protection
When the phase fault runs, it will do great harm to the motor. When the maximum current is
greater than 20% rated current and the minimum current is less than 5% rated current, or when the
imbalance degree of three-phase current is greater than 30%, the fault protection will trip or alarm
within the set time.
Note:
Imax: Maximum current
Imin: Minimum current
Iuf: Degree of current imbalance
Ts1: Delay time of alarm action
Ts2: Delay time of trip action
6.14 Phase sequence protection
When the error of three-phase voltage phase sequence is detected, the protector will trip or
alarm within the set time to protect the safety of the motor.