Controller shows E17 and logs a fault shortly after the generator starts and transfers load.

Safety first: This condition can be extremely dangerous. Immediately open the transfer switch to isolate the generator and utility. Do not operate the system until wiring is verified by a qualified electrician.

• Inspect ATS wiring: With all power sources off and locked out, open the ATS enclosure. Verify that utility and generator conductors are landed on the correct lugs as per the WEN installation manual. Correct any miswiring.
• Check mechanical interlock: Ensure the ATS mechanism physically prevents utility and generator contacts from closing simultaneously. If the interlock is damaged or misadjusted, replace or repair the ATS mechanism.
• Verify neutral and ground: Confirm that neutral and ground connections are made according to WEN and local code requirements. Incorrect bonding can cause nuisance reverse power detection.
• Controller settings: Check any reverse power or backfeed detection settings in the WEN controller and ensure they match the ATS type and system design.
• Professional inspection: Due to the risk of backfeeding the utility, have a licensed electrician or WEN‑authorized technician verify the entire installation before returning the system to service.