Inverter: Sunny Boy 6.0-US

IrondukeIIIrondukeII Registered Users, Users Awaiting Email Confirmation Posts: 1
Our Sunny Boy 6.0-US stopped working and has error code 7702. Not able to reset it. Anyone have a tip on doing so. We're on the utility grid and did not notice the issue until the electric bill arrived.


  • BB.BB. Super Moderators, Administrators Posts: 33,314 admin
    Sounds like a fault/failed relay? Check the AC connections to your main panel... (NOTE: only do these checks if you are "safe" with 120/240 VAC circuits)
    • L1 to L2: ~240 VAC
    • L1 to Neutral: ~120 VAC
    • L2 to Neutral: ~120 VAC
    • L1 to Ground: ~120 VAC
    • L2 to Ground: ~120 VAC
    • Neutral to Ground: 0 Volts (or within a couple volts of zero)
    • If your meter can display frequency--Make sure 60 Hz +/- 1 Hz (doubt your power company has wrong frequency).

    Event 7702 with SB240-10 and Sunny Multigate

    A relay error has occurred.Dec 8, 2020•Knowledge

    Issue Description:
    SB240-10 (module inverter) / Sunny Multigate displays event number 7702 in Sunny Portal or Sunny Explorer.
    In addition, the LED on the Sunny Multigate lights up red.

    A relay error has occurred.

    Corrective Measure:
    Contact your installer for further investigation.

    Events 77, 7701, 7702 or 7703

    Event numbers 77, 7701, 7702 and 7703 indicate a problem related to the relay test.Jan 20, 2021•Knowledge

    Event numbers 77, 7701, 7702 and 7703 indicate a problem related to the relay test.

    Before connecting to the grid, the inverter checks the grid relays and monitors the grid quality. Only if all test results are positive, the relays are switched and the inverter connects to the grid.

    For all 3-phase inverters (STP): Especially in new installations, (but also in existing installations, depending on the grid quality on site)  the error often appears in connection with a shifted neutral point / star point. This can be caused by larger consumers on the grid, for example air conditioners, pumps, large motors and lifts or by a faulty installation.

    Therefore, it is advisable to check the installation with regard to the correct connection of neutral conductor and PE (grounding), not only at the inverter connection but also in the sub-distribution and main distribution, and - depending on the plant size and system configuration - possibly also on the grid / plant transformer. 

    Corrective Measure:
    Please contact your installer for further investigation.
    Other search results:

    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
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