What does VE.Bus Error 11 mean on a Victron MultiPlus-II after a short circuit?

Victron's VE.Bus units, the MultiPlus, MultiPlus-II and Quattro, log numbered errors that show in VictronConnect, on a GX display or on VRM. Error 11 is a relay test fault. The unit tests its relays as part of connecting to AC, and Error 11 means that test failed: either an internal relay is not behaving, or something is back-feeding AC where the unit does not expect it.

Why it follows a short circuit

A hard short on the AC side puts a large current through the transfer path. If Error 11 appeared right after one, a damaged internal relay is the most likely cause, and that is a repair, not a setting.

Checks before you send it in

Rule out the wiring causes first, because they are free:

• Nothing feeding AC-out. A generator, a second inverter or shore power wired onto the AC output terminals instead of AC-in will upset the relay test. Related errors point the same way: Error 5 is overvoltage on AC-out and Error 24 is the switch-over protection detecting AC on the output while inverting. Do not reset and ignore either.
• The short is actually gone. Disconnect the AC output loads and see whether the error clears with nothing connected.
• In a parallel or three-phase set, Error 11 can come with others such as 1 (another phase switched off) or 3 (not all devices found). Note which unit reports Error 11 first; that is the one to look at.
• Read the log. A VE.Bus Smart Dongle or a Cerbo GX shows the error history, and VRM keeps a timeline that makes diagnosis much faster.

If it persists

With the AC wiring confirmed correct and the loads off, a standing Error 11 usually needs service. Victron's warranty runs through the dealer you bought from, so go back to them with a photo of the AC and DC wiring, the error log, the firmware version and a note of the short that preceded it. Be aware that damage from an installation fault is treated differently from a defect; our warranty answer covers how claims are handled.