Detailed Function Description 
 
74
  This parameter is normally used when rated power of inverter is greater than 
rated power of motor. 
  Motor overload protection time: 60s with 200% of rated current. For details, 
please refer to above figure. 
Function 
Code 
Name  Description  Setting Range 
Factory 
Setting 
PB.02 
Threshold of 
trip-free 
70.0~110.0% 70.0~110.0 80.0% 
PB.03 
Decrease rate 
of trip-free 
0.00Hz~P0.04 0.00Hz~P0.04 0.00Hz 
If PB.03 is set to be 0, the trip-free function is invalid. 
Trip-free function enables the inverter to perform low-voltage compensation when DC bus 
voltage drops below PB.02. The inverter can continue to run without tripping by reducing 
its output frequency and feedback energy via motor. 
Notice: If PB.03 is too big, the feedback energy of motor will be too large and may 
cause over-voltage fault. If PB.03 is too small, the feedback energy of motor will be 
too small to achieve voltage compensation effect. So please set PB.03 according to 
load inertia and the actual load. 
Function 
Code 
Name  Description 
Setting 
Range 
Factory 
Setting 
PB.04 
Over-voltage 
stall protection 
0: Disabled 
1: Enabled 
0~1 1 
PB.05 
Over-voltage 
stall protection 
point 
110~150% 110~150
380V:130% 
220V:120% 
During deceleration, the motor’s decelerating rate may be lower than that of inverter’s 
output frequency due to the load inertia. At this time, the motor will feed the energy back 
to the inverter, resulting in DC bus voltage rise. If no measures taken, the inverter will trip 
due to over voltage.   
During deceleration, the inverter detects DC bus voltage and compares it with 
over-voltage stall protection point. If DC bus voltage exceeds PB.05, the inverter will stop 
reducing its output frequency. When DC bus voltage become lower than PB.05, the 
deceleration continues, as shown in following figure.