Monitoring the Inverter - Fault Guide Fault No. 10 - Overcurrent in Hardware Explanation: Hardware overcurrent detection. Cause: N/A Remedial Action: Please contact our Service department. Fault No. 11 - Auxiliary Power Supply Operation Explanation: Power supply of control electronics has failed. Cause: N/A Remedial Action: Please contact our Service department. Fault No. 16 - Overtemperature Explanation: The inverter is too hot. Cause: Poor dissipation of the heat generated by the inverter. Remedial Action: Check whether the flow of air around the heat sinks of the inverter is impeded/blocked. Fault No. 24 - Internal, AFI Defective Explanation: The RCCBs built into the inverter. Cause: Hardware defect. Remedial Action: Please contact our Service department. Fault No. 26, 35, 37 - Fault, Internal Grid Monitoring Explanation: Internal communication fault. Cause: Hardware defect. Remedial Action: Please contact our Service department. Fault No. 27 - Auxiliary Power Supply Stdb Explanation: Too little insolation to enable the electronics to function. Cause: N/A Remedial Action: Wait until the level of insolation is high enough. Fault No. 28 - Fault, ENS/MSD Data CP Explanation: Plausibility check on the measured values. Cause: N/A Remedial Action: Please contact our Service department. Fault No. 32 - Fault, DC Symmetry Explanation: Symmetry error of the electrolytic capacitor of the intermediate DC link. Cause: Defective capacitor. Remedial Action: Please contact our Service department. Fault No. 33, 34 - Offset Error in Standby/Operation Explanation: Offset current or voltage measurement in standby/during operation outside permissible range. Cause: N/A Remedial Action: Please contact our Service department. Fault No. 38 - Fault, Relay Defective Explanation: Grid isolating relay defective. Cause: Hardware defect. Remedial Action: Please contact our Service department. Fault No. 40 - Fault, RAM-Check NOK Explanation: RAM check on startup is not okay. Cause: N/A Remedial Action: Switch the inverter off and on again. Fault No. 41 - Fault, MPP Controller Explanation: Too low an output at too high a DC voltage. Cause: Hardware defect. Remedial Action: Please contact our Service department. Fault No. 42 - Fault, External Explanation: External fault. Cause: A fault from an external source has been reported via the inputs of the inverter. Remedial Action: Test the external source for faults. Models: 25 25 50 55