Chapter 5  Parameter Introductions      75 
EV2000 Series Universal Variable Speed Drive    User Manual 
the CCI input current until CCI input current reaches or 
exceeds the preset value of Ib, or the preset frequency 
reaches fb. 
Stopping process: 
The drive will not stop immediately when the CCI input 
current is reduced to Ib. It will stop its output when the 
CCI input current drops to Ia and the corresponding 
frequency is fa. 
“fa” is the zero-frequency operation threshold defined by 
F9.12. “fb-fa” is the hysteresis of zero-frequency 
operation defined by F9.13. 
This function can enable the drive to enter dormant state 
so as to save energy, besides, the drive will not start at 
the threshold of zero-frequency operation if the 
hysteresis is set properly. 
0
Actual 
frequency 
setting
Primary frequency setting
fa fc fb
CCI current input 
Imax
Imin
Ib
Ia
Ic
Fmin
Fmax
fa: Zero frequency threshold
fb: fa+ zero freq. hysteresis
fc: Freq. corresponding to Ic(CCI input)
primary frequency setting
 
Fig. 5-67 Hysteresis of zero-frequency operation 
F9.14 Preset length 
Range:0.000~65.535km 
【0.000km】 
F9.15 Actual length 
Range:0.000~65.535km 
【0.000km】 
F9.16 Rate of length 
Range:0.001~30.000【1.000】
F9.17 Correction 
coefficient of length 
Range:0.001~1.000【1.000】
F9.18 Perimeter of shaft 
Range:0.01~100.00cm 
【10.00cm】 
F9.19 Number of pulses 
per revolution 
Range: 1~9999【1】 
This group of parameters are used for fixed length 
control. 
The drive inputs counting pulses via terminals (X7 or X8, 
defined as function 44), and calculate length according 
to the number of pulses per revolution (F9.19) and 
perimeter of shaft (F9.18). 
Calculated length
=Number of pulses÷number of 
pulses per revolution
×perimeter of shaft 
The calculated length can be corrected through F9.16 
(times of length) and F9.17(correction coefficient of 
length, and the corrected length is the actual length. 
Actual length 
=calculated length×F9.16÷correcting 
coefficient of length 
When actual length(F9.15)
≥preset length(F9.14), the 
drive will send out a STOP command to stop the drive. 
When the drive restarts, it needs to clear or modify the 
actual length (F9.15), otherwise the drive will not start. 
 Note: 
The actual length (terminal Xi is defined as No.39 function) 
can be cleared by multi-function input terminal. The actual 
length can be calculated only after this terminal is 
disconnected. 
Actual length (setting of F9.15) will be saved after power 
off automatically. 
Function of stopping at fixed length is disabled if F9.14 is 
set to 0, but the calculated length is still effective. 
An example of stopping the motor at fixed length: 
Drive
Motor
Spindle
Speed measuring shaft
Speed 
sensor
 
Fig. 5-68    Fixed length control application 
In Fig. 5-68, a drive drives a motor that rotates a spindle 
via a conveyor belt. Speed measuring device measures 
the line speed of the spindle and send the speed signal 
to the drive in the form of pulses. The drive will count the 
pulses and calculate the actual length. If the actual 
length is longer than the preset length, the drive will stop 
the motor automatically. The operator can remove the 
spindle and close the terminal that is defined as function 
39 to clear the length, and then restart and produce the 
next spindle. 
 Note: 
Functions of stopping the motor at a fixed length are only 
valid for the drive of 45kW or below. 
F9.20 Trip-free operation 
Range:0. 1【0】