InverterS300Verified · sol.ls-electric.com
S300 NTC Open — NTC Open
Trip — immediate stop
CAUSE
Why does it occur?
Occurs when a fault is detected in the temperature detection sensor of the power semiconductor (IGBT), or when there is a problem with the internal sensor connector.
REMEDY · Step by step
How to fix it?
- Check the ambient temperature around the inverter
- If the ambient temperature is high, check whether the inverter fan is operating normally and whether the inside of the panel is well ventilated
- If it occurs when the temperature is not high, inverter inspection is required
- Refer to the authorized automation service center information
Do not reset repeatedly before identifying the cause. Repeated resets while ignoring a trip/alarm can cause secondary damage (IGBT failure, motor winding damage, etc.).
SOURCE
Related manual page
Verified · sol.ls-electric.com
S300 Standard User Manual V1.6 EN (260120)
9.5 Trip/Warning List · 14장 Troubleshooting · p.729 · V1.6 (2026-01-20)