BYD B-Box HV Troubleshooting

Please first follow the article called Commissioning the Solis RHI-1P(5-10)K-HVES-5G with a BYD B-Box HV Battery to ensure the battery has been properly commissioned before attempting any troubleshooting steps

Alarm Codes Related to the BYD Battery

  1. OV-Vbatt1
    • The inverter is detecting abnormally high voltage coming from the battery
    • The nominal DC voltage range of the battery is 320-451V
    • Measure the DC voltage at the battery input terminals with the fuses in and battery switches ON
    • Turn the battery switches OFF and then back ON after a few minutes – measure the voltage again
    • For advanced troubleshooting, contact the Solis USA Service line
  2. OV-Vbatt-H
    • This alarm is similar to OV-Vbatt1 except that in this case there is a battery hardware fault
    • Inspect the communication wires at both ends – do a tug test to ensure they are snug
    • Turn the battery switches off and then back on after a few minutes
    • Follow the commissioning steps found on page 11
    • If the error code persists, the battery BMS is most likely experiencing difficulties 
    • Contact BYD Support 
  3. UN-Vbatt1
    • The inverter is detecting abnormally low voltage coming from the battery
    • With the battery DC fuses pushed in, measure the DC voltage coming from the battery
    • If the voltage is zero, make sure that the battery switch is turned on
    • If the voltage coming from the battery is still zero, verify that the battery has been commissioned
      • Plug into the battery with a laptop
      • Follow the commissioning steps located in the article called "Solis Energy Storage Inverter with BYD B-Box Commissioning"
  4. NO-Battery
    • The inverter is not detecting a battery connected 
    • Go to "Battery Control" in Advanced Settings and select the correct battery
      • Note: if the communication wires are not landed properly, the inverter will continue to display "No Battery" until the wires have been configured and the correct battery selected
    • Turn the battery switch to the OFF position – check the battery fuses in the inverter to make sure they are not blown – replace the fuses if they are – leave the fuses pulled out for now
    • Turn the battery switches ON and then check polarity at the input terminals – turn the switches back off
    • Push the battery fuses in and then turn the battery switches ON
    • Follow the commissioning steps on page 11 to configure the inverter for the BYD Battery
    • Measure the DC voltage coming from the battery – if the voltage is less than 84V contact BYD Support
    • If the voltage is more than 85V and the inverter still says “NO-Battery” after performing these steps, contact Solis USA Service line

BYD USA Support (EFT-Systems Gmbh)

Customer Service E-Mail:



Victor is the author of this solution article.

Did you find it helpful? Yes No

Send feedback
Sorry we couldn't be helpful. Help us improve this article with your feedback.