HNC Electric HV480 Series, Руководство пользователя

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According to the motor overload graph, if the 30 - minute overload is within the current range of 125 % and
135 %, then it can be concluded that the 30 - minute overload motor current IX under the default setting is as follows:
(40-30)÷ (125%-Ix) = (40-15) ÷ (125%-135%)
The result shows that the motor current IX = 129 %, so it can be concluded that the motor needs to overload for
30 minutes at 120 % of the motor current, and the motor overload protection gain:
F9-01=120%÷Ix=120%÷129%=0.93
Note: the user needs to set the value of F9 - 01 correctly according to the actual overload capacity of the
motor. If the parameter setting is too large, it is likely to cause overheating damage to the motor and the
frequency inverter does not give an alarm in time to protect it!
F9 - 02 motor overload warning coefficient 50%
～
100%[80%]
This function is used to give an early warning signal to the control system through do before motor overload fault
protection. This early warning coefficient is used to determine how much early warning is to be given before motor
overload protection. The higher the value, the smaller the advance warning amount
When the frequency inverter output current accumulation is greater than the product of the overload inverse time
limit curve and F9 - 02, the multi-function digital word DO of the frequency inverter outputs the “motor overload
pre-alarm" on signal
F9 - 03 over voltage stall gain 0
～
100 [30]
F9 - 04 stall over voltage point 200.0V
～
2000.0V [760.0%]
F9 - 03 = 0: over voltage stall protection function is invalid.
F9 - 03 non - 0: over voltage stall protection function is valid.
During the speed reduction of the frequency inverter, due to the influence of the load inertia, the actual decrease
of the motor speed may be lower than the decrease rate of the output frequency. At this time, the motor will feed back
electric energy to the frequency inverter, causing the voltage of the DC bus of the frequency inverter to rise. If no
measures are taken, an over voltage fault will occur.
The over-voltage stall protection function detects the bus voltage during the deceleration operation of the
inverter, and compares with the stall over-voltage point F9 - 04. If the stall voltage is exceeded, the output frequency
of the inverter stops falling. When the bus voltage is lower than the stall over-voltage point, the deceleration
operation is implemented again.
F9 - 03 the greater the over voltage stall gain setting, the stronger the ability to suppress over voltage. However,
on the premise that no over voltage occurs, the smaller the benefit increase setting is, the better.
For loads with small inertia, the over-pressure stall gain should be small; otherwise the system's dynamic
response will slow down.
For large inertia loads, this value should be large; otherwise, the suppression effect is not good and over voltage
faults may occur.
Figure 5 - 26 over voltage stall function
F9 - 05 over loss rate gain 0
～
100 [20]
Output frequency
Time
Time
Stall over voltage point