UNB-BUS

Modified on Fri, 17 Nov, 2023 at 7:14 AM




1. Check    for    any    loose    connection    in    MC4 connector.


2. Please   ensure   all   the   MC4   connectors   are properly crimped.


3. Please ensure that DC strings polarity also should be proper.


4. Please check the VOC of all of the PV strings (Voltage should check from connector end after disconnect string from inverter).


5. Use a multi-meter to check the voltages between PV+ and earth, PV- and earth of all the PV strings. It should be decreasing from values between 5% and 95% of single PV module Voc. If voltage stuck on above single module VOC or in decreasing condition if voltage getting increase that means there is some fault with that strings.


6. If system is three phase (Check AC side voltage Phase to Phase, phase to neutral and neutral to earthing.) Always check reading from inverter AC gland end.


7. If system is single phase (Check AC side voltage Phase to neutral, phase to earthing and neutral to earthing.) Always check reading from inverter AC gland end.


8. Stop Ground protect from special setting for an hour then check either inverter is generating or not. If generating then after an hour restore that setting to normal.


9. Take complete reading of information menu like DC1, DC2, DC3, DC4 then VA, VB, VC or VGrid then Status (Error) and Total energy.


10. Take reading from advance info Alarm messages, version, running messages, warning messages.


11. Take ACDB, DCDB close and clear photo, inverter serial no. which is stick on inverter body and inverter complete installation photo.

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