Warning What does this mean?
Your system is down or running degraded, but this is not an immediate safety danger. Work through the safe steps below.
Solis Inverter OV-BUS Error: Meaning, Causes & Safe Fix
Your Solis inverter's internal DC bus voltage went too high (OV-BUS) or too low (UN-BUS). This is an internal fault — note the code and call your installer.
What should I do first?
Two quick questions — we'll point you to the right starting point.
Is this code still showing on your inverter's display?
Is your system producing power right now?
What this code means
OV-BUS ('over DC bus voltage') and UN-BUS ('under DC bus voltage', variants 01/02) are internal faults in the inverter's power stage. The DC bus is an internal high-voltage rail; the manual points to inductor or driver connections — both internal, technician-only areas. The inverter stops operating when either occurs.What is this downtime costing you?
Rough estimate while your system isn't producing. Adjust the numbers to match your setup.
≈ – kWh of lost production per day.
Estimate only — assumes ~80% real-world output vs. nameplate. Actual losses depend on weather, shading, panel direction, and your tariff.
Common causes
- Internal component or connection fault in the inverter's power stage
- Severe grid disturbance upsetting the internal bus regulation
- Failing driver circuitry (technician diagnosis required)
Safe steps to try
Work top to bottom, ticking off each step as you complete it. 0 of 5 done.
Is your inverter still under warranty?
Before paying for a repair, check — your installer may fix this free.
Based on typical standard warranty terms — always confirm with your warranty card or installer paperwork, as terms vary by model, region, and purchase date.
When to call an electrician
Call your installer or the Solis service center if this fault appears at all — bus faults are internal and need professional diagnosis. Have your inverter's serial number and installation date ready, as the manual asks for these when you contact support.
Frequently asked questions
Can I open the inverter to check?
No. The manual states there are no user-serviceable parts inside, and opening it risks electric shock and voids the warranty.
What information should I have when I call support?
The manual asks for: the exact alarm message on the display, your inverter's serial number, the distributor or dealer if known, the installation date, and a description of the problem.
Is it safe to leave the inverter powered with this fault?
The inverter has shut itself down, so it is not operating. Leave it as is, don't keep restarting it, and arrange a professional inspection.
Need a professional?
This fault may need professional diagnosis. Contact a qualified solar electrician in your area.
Sources: meaning and troubleshooting verified against the manufacturer's documentation — Solis S5-GR3P(3-13)K Three Phase Inverter User Manual (Ginlong Solis), Table 9.1