On this page
01. Quick checks you can do first02. What usually causes it03. When to call a technician04. Parts that fix it05. FAQ
If everything goes off in a blackout, either the circuit isn't wired through the inverter output, the inverter is in bypass, or the battery has hit its low cut-off. If computers restart on changeover, the inverter is in a slow transfer mode (APL/appliance) instead of UPS mode, or it's too slow for sensitive equipment. Check the mode and which circuits are on the inverter output.
Key takeaways
- Only circuits wired to the inverter output get backup.
- Bypass mode passes grid power straight through with no backup.
- Low-battery cut-off stops backup early.
- Use UPS mode for computers and networks.
- Servers and network racks may need a true online UPS.
01Quick checks you can do first
- 01Check which sockets have backupTest with the main breaker off. Sockets that go dead aren't on the inverter output.
- 02Check the modeSet UPS mode (fast transfer) if computers restart during changeover.
- 03Check the bypass switchA manual bypass left on means no backup.
- 04Check battery levelIf the battery is already low, the inverter shuts down instead of switching.
- 05Test itSwitch off the incoming supply at the breaker and watch what stays on.
02What usually causes it
| Symptom | Likely cause | Fix |
|---|---|---|
| Whole house goes dark | Circuits not on inverter output | Rewire essential circuits |
| Computers restart on changeover | APL mode or slow transfer | UPS mode or online UPS |
| Nothing switches, display normal | Bypass switch on | Return to inverter mode |
| Switches then dies quickly | Battery low or weak | Charge/test batteries |
| Works sometimes | Loose connection or faulty relay | Technician check |
03When to call a technician
- Circuits need rewiring to the inverter output.
- Computers or servers drop on every outage.
- The inverter clicks but doesn't switch.
- You need a changeover switch or distribution board work.
Running this across several sites or branches? A Qyvea maintenance contract catches these faults on scheduled visits, with a written report after each one.
04Parts that fix it
05Frequently asked questions
Why do my computers restart when power goes even with an inverter?
Many inverters take 10–20 ms to switch, which some PCs can't ride through. Use UPS mode or an online UPS for computers.
Can an electrician add more circuits to my inverter?
Yes, as long as the inverter can carry the extra load. We check the sizing first.
What is bypass mode?
A setting or switch that feeds the house straight from the grid, used for maintenance. In bypass there is no backup.
