LS Industrial Systems SV-iV5 Series - Encoder S;W Error Detection (PAR_14 ~ 15)

6. Function Description
6-27
Setting Description Encoder pulse (In FWD RUN)
A Phase Lead
A phase leads in FWD rotation.
B phase leads in REV rotation.
B Phase Lead
B phase leads in FWD rotation.
A phase leads in REV rotation.
If you set “Enc Err Chk” of PAR_12 to “Yes”, when there is disconnection or misconnection of encoder, encoder error
is detected and show the encoder abnormity sign. In the case of open collector method of encoder, it isn’t possible to
detect encoder error. So set PAR-12 to “No”.
Improper setting of encoder parameters may deteriorate accurate speed control and lead to “overcurrent” or
“overvoltage” trips. Refer to chapter 9 “Troubleshooting”.
Code LCD display Description Setting range Unit
Factory
setting
PAR_10 Enc Pulse Number of encoder pulse 360 ~ 4096 1024
PAR_12 Enc Err Chk Encoder error check
Yes
No
Yes
PAR_13 Enc LPF Encoder LPF time constant 0 ~ 100 ms 1
6.3.4 Encoder S/W error detection (PAR_14 ~ 15: Encoder error detection time, encoder error
reference speed)
To achieve correct motor speed detection and control using encoder, proper wiring of encoder and motor should be
preceded. If operation is continued with faulty wiring of Encoder/Motor, overcurrent flows to the motor, damaging the
motor. Therefore, encoder should have functions to detect encoder input error and wrong wiring.
SV-iV5 can monitor encoder H/W error by setting PAR_12 to “Yes” and it monitors encoder pulse signal input status
to detect H/W faults such as encoder disconnection error. However, wrong wiring error cannot be detected with this
function. In this case, perform “Rotational Auto-tuning”. Set PAR_23 (AutoTuneType) to “Rotational” and perform
Encoder Test. Then wiring problem can be detected by applying voltage and checking speed detection level while motor
is running.
There are some loads (ex. Elevator) performing Encoder Test described above is difficult. To solve this fault, iV5
adopts the following functions to detect S/W faults.
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
A
B
A
B