
A.1 Power Supply
Ensure that the voltage class of the inverter is consistent with that of the grid
Fault Code Display Fault Type Possible Cause Solution
OL2 E12 Inverter overload
• R/S/T input phase loss or violent uctuation.
• Input-side screws loosened.
• Check for abnormal input power and loose
input cables.
• Set parameters to screen out the fault.
SPI E13 Input phase loss
• Output cables broken or short connected to
the ground.
• U/V/W output phase loss or seriously
asymmetrical 3PH loads.
• Check for loose or broken output cables.
• Check for sharp load uctuation and motor
3PH resistance imbalance.
SPO E14 Output phase loss
• Air duct blocked or fan damaged.
• Ambient temperature too high.
• Long-time overload running.
• Ventilate the air duct or replace the fan.
• Keep good ventilation to lower ambient
temperature.
• Select an inverter with larger power.
OH2 E16 Inverter module overheat
• Improper baud rate.
• Communication line fault.
• Incorrect communication address.
• Communication suffers from strong
interference.
• Set a proper baud rate.
• Check the communication port wiring.
• Set the communication address correctly.
• Replace or change wiring to enhance anti-
interference.
CE E18 RS485 communication fault
• Motor capacity and inverter capacity
mismatched.
• Improper motor parameter setting.
• Autotuned parameter settings deviate
sharply from the standard ones.
• Autotuning timeout.
• Change the inverter model.
• Set the motor type and nameplate
parameters correctly.
• Empty the motor load and re-perform
autotuning.
• Check motor wiring and parameter settings.
• Check whether the upper limit frequency is
greater than 2/3 of the rated frequency.
tE E20 Motor autotuning fault • R/S/T input phase loss or violent uctuation.
• Input-side screws loosened.
• Check for abnormal input power and loose
input cables.
• Set parameters to screen out the fault.
PIDE E22 PID feedback ofine fault • PID feedback ofine.
• PID feedback source disappears.
• Check PID feedback signal wires.
• Check PID feedback source.
dEu E34 Speed deviation fault • Load too heavy or stalled.
• Check for overload, increase speed deviation
detection time, or prolong ACC/DEC time.
• Check motor parameter settings and re-
perform motor parameter autotuning.
• Check speed loop control parameter settings.
STo E35 Mal-adjustment fault
• Load exception.
• Incorrect SM parameter settings.
• Autotuned motor parameters inaccurate.
• Inverter disconnected from the motor.
• Flux weakening application.
• Check for overload or stalling.
• Check motor parameter and counter EMF
settings.
• Re-perform motor parameter autotuning.
• Increase maladjustment detection time.
• Adjust ux weakening coefcient and current
loop parameters.
STO E40 Safe torque off • Safe torque off function is enabled by
external forces. • /
STL1 E41 Exception occurred to safe circuit of
channel H1 • The wiring of STO is improper.
• Fault occurred to external switch of STO.
• Hardware fault occurred to safety circuit of
channel H1/H2.
• Check whether terminal wiring of STO is
proper and rm enough.
• Check whether external switch of STO can
work properly.
• Replace the control board.
STL2 E42 Exception occurred to channel H2 safe
circuit
STL3 E43 Exception occurred to channel H1 and
channel H2 • Hardware fault occurred to STO circuit. • Replace the control board.
Appendix A - Optional Peripheral Accessories
A.2 Cables
The sizes of the input power cable, and motor cables must meet the local regulation.
• The input power cables, and motor cables must be able to carry the corresponding load currents.
• The maximum temperature margin of the motor cables in continuous operation cannot be lower than 70°C.
• The conductivity of the PE grounding conductor is the same as that of the phase conductor, that is, the cross-sectional areas are the same.
Check the insulation conditions of the input power cable of an inverter according to the local regulations before connecting it.
Table A 1 Cable Specications (SD1 Models only)
Model Recommended Cable Size (mm2)Size of Connectable Cable (mm2)Terminal Screw Terminal Torque
(Nm)
RST
PE
RST
PE, (+) PE
UVW UVW
SD1-2.5A-21 1.5 1.5 1~4 1~4 1~4 M3 0.8
SD1-4.2A-21 1.5 1.5 1~4 1~4 1~4 M3 0.8
SD1-7.5A-21 2.5 2.5 1~4 1~4 1~4 M3 0.8
SD1-10A-21 2.5 2.5 1~4 1~4 1~4 M3 0.8
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