A90 series Inverter User Guide 34 2.communication cable disconnected 2.Check whether the communication cable is disconnected. 3.Adjust the communication overtime (F10.03). E17 Invertor Temperature Sensor Abnormality 1. Temperature sensor of inverter is off or short-circuited. 1.Seek for technical support E18 Soft Start Relay Off 1. Power off at running status. 2. Input voltage phase loss. 3. Wiring terminals of input voltage are loosened. 4. Input voltage drops too much. 5. Aging of switch contact on input power supply. 1. Shut down power supply after the inverter stopped 2. Check the input voltage and check power terminals wiring. 3. Tighten screws of input wiring terminal. 4.
Check air switch and contactor. E19 Current Detection Circuit Abnormality 1. Detection circuit of drive board or control board is damaged. 1. Seek for technical support. E20 Stall Fault 1.The set deceleration time is short. 2. Dynamic brake abnormality at ramp-to-stop. 3. The load is too heavy. 1.Extended deceleration time. 2.Check the brake resistor and brake unit and wiring. 3.Check whether the motor is driven by another load can not stop. E21 PID Feedback Disconnection 1. PID feedback is higher than upper limit F09.24 or lower than lower limit F09.25, depending upon types of sensors. 1. Check whether the feedback line falls off; 2. Check whether the sensor works abnormally; 3.
Adjust the feedback disconnection detection value to a reasonable level. E24 Autotune Abnormality 1. Press STOP/RESET in the parameter autotune. 2. In autotune, the external coast-to-stop terminal FRS=ON. 3. Motor is not connected to output terminal of inverter. 4. Motor is not disconnected from load for rotational autotune. 5. Motor fault. 1. Press STOP/RESET to reset. 2. Check the connection between inverter and motor. 3. Motor is disconnected from load for rotational autotune. 4. Check motor. E26 Offload Protection 1.The motor is not connected, or the motor does not match. 2.Appeared off the overload 1.check the wiring, replace the matching motor 2.check the equipment