IGBT matrix replacement

IGBT matrix replacement means swapping out the IGBT power switching assembly inside an inverter. It is a corrective repair for a power stage fault. O&M practice treats it as an as-needed inverter repair carried out by an inverter specialist, normally covered under the inverter warranty. Inverter fault codes such as power stage error, power stage trip and IGBT temperature can point to a problem in the power stage. Removing and installing the assembly takes two people, because the heat sink can fall off the back of the inverter. Take care not to lose the O-rings. After the new assembly is fastened to the drop-in panel, refit the AC bus bars, inductor wires and snubber capacitors to the specified torques. Then reconnect the gate adaptor ribbon cable with the latches closed.

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• sentence 1: support check: partial - The table lists 'Replace IGBT matrix in inverter' as a Repair/Inverter service, but it doesn't define it as swapping the power switching assembly or tie it to a power stage fault.
• sentence 3: support check: partial - The three fault codes are listed, but the passages don't say they point to a power stage problem; the names only imply it.
• sentence 5: support check: partial - The sequence is stated (fasten to the panel, then bus bars, inductor wires and snubbers, then the ribbon cable with latches closed). However, one snubber cap is explicitly not torqued at first, and installation takes two technicians, so 'specified torques' is slightly overstated. The core is present.
• sentence 1: review: partial - The NREL table lists 'Replace IGBT matrix in inverter' as an as-needed repair, but neither passage calls it a power switching assembly or ties it to a power stage fault. -->