DC link

The DC link is the internal DC stage of an inverter that feeds the inverter bridge. The inverter monitors the DC link and reports a fault when it detects overvoltage there. The cause can be inside the inverter or outside it. Central inverters can report DC link overvoltage as its own alarm bit over SCADA, separate from the DC input overvoltage alarm. The DC link is charged through a pre-charging circuit before operation. Inverters flag both a defective pre-charging circuit and a DC link that could not be charged enough. For these DC link faults, the corrective step given is to contact the manufacturer's service line.

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• sentence 1: support check: partial - The passage mentions the DC link of the inverter bridge, but it does not say the DC link is an internal DC stage that feeds the bridge.
• sentence 4: support check: partial - Both the defective pre-charging circuit and the DC link that could not be charged enough are flagged, but no passage says the DC link is charged through a pre-charging circuit before operation.
• sentence 1: review: partial - The passage mentions 'the DC link of the inverter bridge' but does not say the DC link is an internal DC stage that feeds the bridge.
• sentence 4: review: partial - Both faults (a defective pre-charging circuit and a DC link that could not be charged enough) are shown, but no passage says the DC link is charged through the pre-charging circuit before operation. -->