- Solar and energy
- Solar inverter
VE.Bus Error 8
Victron Error 8 on a MultiPlus-II inverter: ground relay test
Risk level
High
Professional inspection is recommended.
Urgency
High
Quick answer
The MultiPlus-II or EasySolar-II inverter/charger failed the self-test of its ground relay. Check the detailed error on the GX device (GND Relay Error, PE2 Open or PE2 Closed) and tell the installer without touching the wiring.
Safety first
Stop and check this first
- The ground relay ensures the output earth leakage breaker works when the unit runs without grid. Until Error 8 is resolved, do not change wiring or bridge the neutral yourself.
- Note the error counter before restarting anything. Victron says the stored error may be old and counters must be compared after the next shutdown.
Safe checks you can perform
- Detailed error on the GX device
- Error counter and when it appears
- Front panel LEDs
- Model and serial number
- Neutral, earth and output loads
Leave these tasks to a qualified professional
- Do not attempt this professional task: Hardware identification by serial number
- Do not attempt this professional task: Neutral, earth and load test
- Do not attempt this professional task: Replacement only for a repeated, located fault
- Do not attempt this professional task: Firmware update and configuration
What a technician must be able to justify
Technician visit
These are the steps they must carry out and show you. Tick them as they work: if steps are skipped, do not accept a part swap.
These are not instructions for opening or handling the equipment yourself. They are the checks that should support a technical conclusion.
Hardware identification by serial number
What they doThe technician compares model and serial number with Victron's table to know whether the unit checks the relay with an auxiliary contact or by measuring voltage between earth and neutral.
They must show youmodel, serial number and which version it is.
In writingthe hardware version identified.
Neutral, earth and load test
What they doOn old hardware, the technician checks output neutral, any neutral bypass against the configured grid code and continuity between neutral and earth with a multimeter and loads disconnected.
They must show youthe neutral to earth continuity reading and a clean switch to grid after the fix.
In writingwhich wiring or load caused the fault.
Replacement only for a repeated, located fault
What they doOn new hardware, if one specific unit repeatedly shows GND Relay Error, Victron says that unit should likely be replaced.
They must show youthe error counter rising on that unit.
In writingserial number of the replaced unit and the reason.
Firmware update and configuration
What they doThe technician updates VE.Bus and GX device firmware, as Victron asks for any problem, and reviews the grid code configuration.
They must show youfirmware versions before and after.
In writingthe versions installed and whether the error returned.
Before accepting a part or repair
Nothing has been shown yet. Do not accept a part swap based on the code alone.
Follow these steps
Note: Follow the documented order. An error code identifies the affected system, but it does not prove by itself which part has failed.
Detailed error on the GX device
- Who:
- you, no tools.
- How:
- on the GX device screen or remote console, check the detailed error for each inverter/charger: GND Relay Error, Error: PE2 Open or Error: PE2 Closed.
- Result that matters:
- which variant appears and on which unit, if there are several.
- If PE2 Open or PE2 Closed appears:
- note which, as it shows whether the relay was measured open or closed when it should not be.
- If GND Relay Error appears:
- note on which unit, as the installer will check that one first.
- Evidence to keep:
- screenshots of the error page of each unit.
Evidence: VE.Bus Error Codes
Error counter and when it appears
- Who:
- you, no tools.
- How:
- note the Error 8 counter shown by the GX device and watch whether the fault appears when the grid returns or the generator starts.
- Result that matters:
- Victron explains the error shown may be old, because it is stored in memory, and that the relay is tested when switching to the grid.
- If the counter has not increased:
- the error shown may be old rather than current.
- If it increases every time the unit switches to the grid:
- the fault is current and the installer must check it.
- Evidence to keep:
- photo of the counter with date and time, before and after.
Evidence: VE.Bus Error Codes
Front panel LEDs
- Who:
- you, looking at the front without opening the unit.
- How:
- check there is no AC output and whether the inverter on LED flashes in opposition to the charge LEDs; with code 8, bulk is off and absorption and float are on.
- Result that matters:
- confirming code 8 on the unit itself even without a GX device.
- If the pattern matches:
- it is VE.Bus code 8; record a short video of the LEDs.
- If the pattern is different:
- it is another VE.Bus code and the manual table gives its meaning.
- Evidence to keep:
- video of the LEDs during the error.
Evidence: MultiPlus-II 230V Rev 14 - 07/2026
Model and serial number
- Who:
- you, reading the label without opening the unit.
- How:
- note the model and serial number from the rating label of each unit.
- Result that matters:
- Victron diagnoses differently depending on whether the hardware predates the late 2020 change.
- If it is a MultiPlus-II 48V 3kVA or 5kVA, 24V 3kVA, their GX versions or EasySolar-II 48V 3kVA:
- the installer compares the serial number with Victron's table.
- If it is another model:
- Victron says it has the new hardware from first production.
- Evidence to keep:
- photo of the label.
Evidence: VE.Bus Error Codes
Neutral, earth and output loads
- Who:
- qualified electrical installer.
- How:
- on old hardware, check whether output neutral is tied to earth outside the unit, whether neutral is bypassed without being configured and, with loads disconnected, that there is no continuity between neutral and earth.
- Result that matters:
- whether the system switches to the grid without error with loads disconnected.
- If it switches without error:
- the fault is in the output wiring or a load; reconnect them one at a time.
- If it fails the same way, or the hardware is new and it repeats:
- it points to the relay or its detection in that unit.
- Evidence to keep:
- report with each test and its result.
Victron says these steps are for trained professionals: AC and DC voltages can be lethal. You do not open the unit or touch the wiring.
Evidence: VE.Bus Error Codes
Still not solved
If the error persists, stop here. See what the technician must do and show you.
Where this code applies
A code is meaningful only inside the right product and version context.
Primary scope
- System
- Solar and energy
- Brand
- Victron Energy
- Product type
- Solar inverter
Known code variants
- MultiPlus-II error 8
- Victron error 8
- Victron fallo relé de tierra
- Victron ground relay test failed
- Victron PE2 open
What it means
The ground relay connects the AC output neutral to the chassis when no grid is present, so the earth leakage breaker on that output works. The unit tests it closed while inverting off grid and open when switching to the grid. Error 8 means the measurement did not match. On units built before the late 2020 change, neutral out tied to earth, an unconfigured neutral bypass or leakage in the loads can cause it; newer units only check the internal relay. The code alone does not confirm the relay is faulty.
Warnings and stop conditions
- Higheditorial warning
The ground relay ensures the output earth leakage breaker works when the unit runs without grid. Until Error 8 is resolved, do not change wiring or bridge the neutral yourself.
Evidence: VE.Bus Error Codes · MultiPlus-II 230V Rev 14 - 07/2026
- Mediumsource verified
Note the error counter before restarting anything. Victron says the stored error may be old and counters must be compared after the next shutdown.
Evidence: VE.Bus Error Codes
Symptoms and causes
Probable causes · in order
- Ground relay or its detection (new hardware)Possible
On units with the new hardware, Victron says that if a unit repeatedly shows GND Relay Error, that unit has a relay issue and should likely be replaced. The serial number tells which hardware it is.
Evidence: VE.Bus Error Codes
- Neutral out tied to earth outside the unitPossible
Old hardware only: if AC out neutral is connected to earth externally, the unit always detects that the relay fails to open. It shows when switching to the grid.
Evidence: VE.Bus Error Codes
- Neutral bypassed without being configuredPossible
AC in neutral joined to AC out neutral while the configured grid code does not reflect it. It is a wiring or configuration error and appears when switching to the grid.
Evidence: VE.Bus Error Codes
- Leakage or short in the loadsPossible
A defect in the output wiring or in a connected appliance can join neutral and earth. It is isolated by disconnecting the loads and testing the switch to grid again.
Evidence: VE.Bus Error Codes
Virtual technician
Does VE.Bus Error 8 still appear after these checks?
Answer a few questions to narrow down the likely cause and the safest next action. Guidance only - it never replaces a professional.
Sources and technical references
- 1
Victron Energy · 2024 · official_doc
- 2
MultiPlus-II 230V Rev 14 - 07/2026
Victron Energy · 2026 · manual
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