The common fault code of the inverter

- Jul 25, 2019-

 With the continuous promotion of the application of inverter technology, user-friendly, the phenomenon of failure and treatment methods in the use of the inverter are cited below.

(1) Fault P.OFF

 The power-on display of P.OFF is displayed after a delay of 1 to 2s, indicating that the drive is in standby. In the application, if the inverter powered up has been displayed P.OFF without jumping 0 phenomenon, the main reason is the input voltage is too low, input power supply is not phase-deficient and the inverter voltage detection circuit failure, processing should first measure the power supply three-phase input voltage, R, S, T terminal normal voltage is three-phase 380V, If the input voltage is below 320V or the input power supply is out of phase, the external power supply should be corrected.

 If the input power supply can be judged to be the inverter internal voltage detection circuit or lack of phase protection fault, for the G1/P1 series 90kW and above model inverter, the main cause of the fault is the internal phase-out detection circuit abnormal, the lack of phase detection circuit consists of two single-phase 380V/18.5V transformer and rectifier circuit, Most of the causes of the failure are detection of transformer failure, processing can be measured whether the output voltage of the transformer is normal.

(2) Fault ER08

 The ER08 fault code for the drive indicates that the drive is in an undervoltage fault state. The main reasons are the input power supply is too low or lack of phase, the internal voltage detection circuit of the inverter is abnormal, and the main circuit of the drive is abnormal. The universal inverter voltage input range is 320V to 460V, in practice when the inverter is fully loaded, when the input voltage is below 340V may occur under voltage protection, then the grid input voltage or the use of the inverter derate should be increased; Can be judged to be the drive internal fault. When the KS contactor in the main circuit jumps off so that the current limiting resistance is connected to the main circuit in series while the drive is running, then if the drive belt load operation will cause an ER08 fault, then it can be ruled out whether the contactor is damaged or the contactor control circuit abnormal; The reason for the ER08 alarm is mostly voltage detection circuit failure, the general frequency detector voltage detection circuit for a set of output of the switching power supply, after sampling, comparison circuit to the CPU processor, when the set value is exceeded, the CPU according to the comparison signal output fault blocking signal, blocking IGBT, while displaying the fault code.

(3) Fault ER02/ER05

 The fault code ER02/ER05 indicates that the drive has a flow or overvoltage fault in the deceleration, mainly because the deceleration time is too short, the load feedback energy is too large and can not be released in time. If the motor drives a load of high inertia, when the frequency of the inverter (i.e. the synchronous speed of the motor) may decrease, the actual speed of the motor may be greater than the synchronous speed, then the motor is in a power generation state, this part of the energy will be returned to the DC circuit through the inverter inverter inverter inversion circuit, so that the drive has excessive pressure or overcurrent protection. On-site processing without affecting the production process can extend the deceleration time of the inverter, if the load inertia is large, and requires a certain period of time when the shutdown, to add external brake resistance and brake unit, G2/P2 series inverter 22kW below the model are built-in brake unit, just add external resistance brake can, Resistance options can be selected according to the standard in the product description, and for models with a power of 22kW or more, additional brake units and brake resistors are required.

 ER02/ER05 fault generally only occurs during the inverter deceleration shutdown process, if the drive in other operating states of the fault, it may be the inverter inside the switching power supply part, such as voltage detection circuit or current detection circuit abnormal caused.

(4) Fault ER17

 Code ER17 indicates a current detection fault, universal inverter current detection generally uses current sensor, by detecting the inverter two-phase output current to achieve the drive operating current detection, display and protection function, the output current through the current intelligent sensor output linear voltage signal, by amplification of the comparison circuit to the CPU processor, The CPU processor determines whether the drive is in an overcurrent state according to different signals, and if the output current exceeds the protection value, the fault-blocking protection circuit action blocks the IGBT pulse signal to achieve protection function.

 The main reason for er17 failure of the inverter is the current sensor fault or the current detection amplification comparison circuit anomaly, the former can be solved by replacing the sensor, the latter is mostly the relevant current detection IC circuit or IC chip operating power supply anomaly, can be resolved by replacing the relevant IC or repair related power supply.

(5) Fault ER15

 Code ER15 indicates the inverter module IPM, IGBT fault, the main reason is the output to the ground short circuit, the inverter to the motor cable is too long (more than 50m), the inverter module or its protective circuit failure. On-site processing first remove the motor line, measure the inverter inverter inverter module, observe the output for a short circuit, while checking whether the motor to the ground short circuit and whether the motor line is beyond the permitted range, such as the above is normal, may be the inverter internal IGBT module drive or protection circuit abnormal. General IGBT overcurrent protection is the tube pressure drop action when the IGBT on-on is detected.

 When the IBBT normal on its saturation pressure drop is very low, when the IGBT overcurrent tube pressure drop VCE will increase with the increase of short-circuit current, increase to a certain value, the detection diode DB will be anti-wizard pass, at this time the reverse current signal by the IGBT drive protection circuit to the CPU processor, CPU blocking IGBT output, CPU blocking IGBT output, to achieve protection. If a diode DB is detected for damage, the drive will have an ER15 fault and the detection diode can be replaced to troubleshoot during field processing.

(6) Fault ER11

 ER11 fault indicates that the drive overheated, the main possible reasons are: wind channel obstruction, high ambient temperature, cooling fan damage does not turn and temperature detection circuit anomalies. On-site processing first judge whether the frequency converter is indeed too high temperature situation, if the temperature is too high can first be corrected according to the above reasons, if the frequency converter temperature under normal circumstances ER11 alarm, the cause of the fault is the temperature detection circuit failure. The seven-unit inverter module used in the following models of Comvo 22kW has a temperature element, if this part of the circuit fault in the module will also appear ER11 alarm, on the other hand, when the temperature detection of abnormal computing circuit will also appear the same phenomenon.