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Chapter 6 Parameter Description
92
changed output current below protective motion value, thus ensuring continuous and reliable operation of
system. When current exceeds a certain value (PA.05), the inverter will turn into current limit status.
When operating under constant speed, maintain stable load capability without producing over current
error by current limit. When loads mitigate, exit the current limit status automatically, and return to work
properly. The function is especially applied to applications of suddenly changed speed or load.
Note:
Current limit current PA.05 is proportion of rated current of inverter. When torque load varies:
20.0~150.0%.
Under the current limit status, the speed of motor will decrease. The current limit function is not
appropriate for systems that will not permit reduce speed, for example lifter, otherwise will loss
of control.
Unit place: Over
−
voltage adjustment: When motor with large inertial load stops rapidly, or a short
−
time
regenerative braking happens for load abrupt changes when the motor operates, DC bus voltage of
inverter will rise, thus may result over
−
voltage protective motion. The function of voltage adjustment is in
this case, decrease the braking torque to control the DC bus voltage to prenvent over voltage alarm
through adjust output frequency and auto prolong deceleration time.
Note: If energy
−
consumption braking is applied and braking unit (PA.09=1) has been set and applied, the
function becomes invalid.
Tens place: Under
−
voltage adjustment: When power supply voltage decreases or instantaneous
power
−
off; DC bus voltage will also decrease.The function of under
−
voltage adjustment is decrease the
motor rotating speed through decrease the output frequency, the load inertial energy feedback to DC
side to keep DC voltage higher than the under valtage value,avoid stop by under voltage.Under voltage
function is very effective in applications such as centrifugal pump and fan.
Hundreds place: Overmodulation: This function is used to increase output voltage of inverter and ensure
the output capability of the inverter under low grid voltage or under heavy load.
Display of operation panel
Unit place
Over
−
voltage adjustment:
0: No action; 1: Action
Tens place
Under
−
voltage adjustment:
0: No action; 1: Action
Hundreds place
Overmodulation:
0: No action; 1: Action
By setting PA07, ensure that output voltage will decrease automatically as the loads decrease under
proper operation. The inverter maximally decreases reactive power to offer further energy savings.
Adjust the parameter according to real load conditions. The larger the parameter is, more visible the
energy saving effect achieves, and the longer the response time lasts for the inverter converting from
energy saving condition to proper operation status.
PA.06
Voltage adjustment function
0 ~ 111(101)
PA.07
Energy-saving coefficient
0 ~ 50 %(0%)