Code
LCD display
Description
Setting range
Unit
Factory
setting
PAR_14
EncFaultTime
Encoder error detection time
0.00 ~ 10.00
sec
0.00
PAR_15 EncFaultPerc
Encoder error reference
speed
0.0 ~ 50.0
%
25.0
PAR_21
Rated-Slip
Motor rated slip
10 ~ 250
rpm
When encoder/motor wiring is reversed, motor cannot perform acceleration due to overcurrent. Encoder S/W error
detection is adopted to detect the errors such as wrong wiring and incorrect pulse input during normal operation, not
during Auto-tuning. Inverter determines encoder error if motor speed is not accelerated proportional to operating time
and target speed after PAR_14 EncFaultTime elapses and polarity does not match.
To activate S/W error detection function, set CON_01 = Speed, Auto Tuning is not selected and set EncFaultTime
except 0. If run command is removed before “EncFaultTime” elapses or acceleration is turned to deceleration due to
target speed change, inverter cannot detect encoder S/W error. Inverter determines encoder S/W error by comparing
motor speed and Target speed XEncFaultPerc while operation status is acceleration after EncFaultTime elapses.
Encoder S/W error detection is performed only once after operation starts and activates when target speed becomes
twice the rated slip. For example, when target speed is 500(rpm) and rated slip is 40(rpm), the detection active level is
80(rpm).
E ncFaultTime
(PAR_14)
Run
command
(PAR_21)×2
(a) FUN_02= Keypad 1 or Keypad 2
(b) FUN_02= Analog or Up/Down Operation
Rated slip
Motor
speed
(rms)
Speed
reference (rms)
Speed reference
Motor speed
Target speed
if 80% of PAR_14 elapses, target speed and motor
speed begins accumulated and comparing their
polarity. after PAR_14 elapses, each cumulative
value is calculated by mean value.
Is motor speed rms value> target speed
rms x PAR_14?
and is the rotating direction the same?
Speed reference
Motor speed
Target speed
Time elpased begins counting from the point
target speed becomes twice the PAR_21.