
Setting 1: Decelerate Using C1-02
If the current exceeds the Stall Prevention level set in parameter L3-06, the drive decelerates at Decel Time 1 (C1-02).
Once the current level drops below the value of L3-06 minus 2% for 100 ms it accelerates back to the frequency reference
at the active acceleration time.
Setting 2: Decelerate Using C1-04
Same as setting 1 except the drive decelerates at decel time 2 (C1-04).
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L3-06: Stall Prevention Level During Run
Sets the current level for Stall Prevention During Run. Depending on the setting of parameter L3-23 the level is
automatically reduced in the constant power range (speed beyond base speed).
No.
Name
Setting Range
Default
L3-06
Stall Prevention Level During Run
30 to 150
<1>
<1>
<1> The upper limit and default for this setting is determined by C6-01 and L8-38.
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L3-23: Automatic Stall Prevention Level Reduction
This function reduces the Stall Prevention during run level in the constant power range.
No.
Name
Setting Range
Default
L3-23
Automatic Reduction Function Selection for Stall Prevention
during Run
0 or 1
0
Setting 0: Disabled
The level set in L3-06 is used throughout the entire speed range.
Setting 1: Enabled
The Stall Prevention level during run is reduced in the constant power range. The lower limit will be 40% of L3-06.
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Overvoltage Suppression Function
This function suppresses overvoltage faults by slightly increasing the output frequency when the DC bus voltage rises. It
can be used to drive loads with cyclic regenerative operation, such as punch presses or other applications that involve
repetitive crank movements.
The output frequency is adjusted during ov suppression so that the DC bus voltage does not exceed the level set in parameter
L3-17. In addition to the parameters explained below, ov suppression also uses these settings for frequency adjustment:
• DC bus voltage gain L3-20
• Deceleration rate calculations gain L3-21
• Inertia calculations for motor acceleration time L3-24
• Load inertia ratio L3-25
Note: 1.
The motor speed will exceed the frequency reference when overvoltage suppression is triggered. Consequently, overvoltage suppression
is not appropriate in applications that require a perfect match between the frequency reference and the actual motor speed.
2.
Disable overvoltage suppression when using a braking resistor.
3.
Overvoltage may still occur if there is a sudden increase to a regenerative load.
4.
This function is enabled only when operating just below the maximum frequency. Overvoltage suppression does not increase the output
frequency beyond the maximum frequency. If this is required by the application increase the maximum frequency and change the base
frequency setting.
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L3-11: Overvoltage Suppression Function Selection
Enables or disables the overvoltage suppression function.
No.
Name
Setting Range
Default
L3-11
ov Suppression Function Selection
0 or 1
0
Setting 0: Disabled
The output frequency is not adjusted. A regenerative load may trip the drive with an overvoltage fault. Use this setting if
braking options are installed.
Setting 1: Enabled
When the DC bus voltage rises due to regenerative load, an overvoltage fault is prevented by increasing the output
frequency.
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L3-17: Target DC Bus Voltage for Overvoltage Suppression and Stall Prevention
Sets the target DC bus voltage target level used by the overvoltage suppression function (L3-11 = 1) and Intelligent Stall
Prevention during deceleration (L3-04 = 2).
5.8 L: Protection Functions
SIEP C710606 20 OYMC AC Drive - V1000 User Manual
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Parameter Details
7/16/2008-13:23