Contactor fails to open

The inverter reports that a contactor was commanded to open but did not open properly. On the Yaskawa SGI-XTM it shows on the user interface as DC Cont. Err and is also written to the event log. SMA equipment reports the same kind of fault as a tie contactor, tie switch or load-shedding contactor that will not open. Some inverters raise a general contactor failure, where the contactor can fail either open or closed. In that case a power cycle is the first step, and technical support is called if the error stays. A contactor that will not open cannot be fixed in the field. The manufacturers say to contact service and have an authorized provider inspect and repair the inverter.

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• sentence 1: support check: partial - Passages say the contactor failed to open, but none states it was 'commanded' to open; that detail is implied only.
• sentence 4: support check: partial - The AC Contactor Failure row states fail open or closed, power cycle first, then contact Technical Support; 'some inverters' is a generalization, and the row is AC grid contactor specifically.
• sentence 5: support check: partial - Passages say to contact service and have an authorized provider inspect/service, but do not say it cannot be fixed in the field or mention repair explicitly. -->