SV-iS7 User Manual - Inverter Drive Supermarket

Chapter 10 Protective Functions
PRT-50 Stall Prevent : Stall preventing action can be selected during acceleration/deceleration or steady speed
operation. If the dot of the switch is above, the appropriate bit is set and it below, it does not operate.
Bit set(ON) : Bit setting canceled(OFF) :
Setting Items Function
bit3 bit2 bit1 Bit 1 is the first on the right of the display.
� Selection of stall preventing function during accelerating operation
� Selection of stall preventing function during steady speed operation
� Selection of stall preventing function during decelerating operation
001 : Stall Prevention during Acceleration
Acceleration stops and deceleration begins if the inverter output current during acceleration is higher than the set stall
level(PRT-52, 54…). If the current stays at higher than the stall level, it decelerates to the start frequency(DRV-19
Start Freq). Acceleration resumes if the current goes down below the set level during the stall preventing operation.
010 : Stall Prevention during Steady Speed
The output frequency is automatically reduced for deceleration if current is higher than the set stall level during steady
speed operation, as the stall preventing function during acceleration. Acceleration resumes if the load current goes
down below the set level.
100 : Stall Prevention during Deceleration
The DC voltage of the DC power part is kept below a certain degree and deceleration is conducted to prevent over
voltage trip during deceleration. Therefore the decelerating time might be longer than the set time according to the
load.
Caution
Be careful because the decelerating time might be longer than the set time according to the load
if the stall preventing function is set during deceleration.
The actual accelerating time becomes longer than the set acceleration time because deceleration
is interrupted if stall preventing function gets active during acceleration.
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