Error 21

Victron Energy Power Converter: “Error 21”

warning RV power converter problems

Safety Always isolate the DC input and output before disconnecting terminals to avoid arcing and short circuits. A faulty current sensor can mean charging is uncontrolled, so do not keep cycling a unit that repeatedly faults.

What it means

Current sensor problem. The measured charge current is out of the expected range, suggesting a current-measurement fault. This error does not clear by itself.

Most likely causes

Transient wiring/connection issue affecting current measurement common
Internal current-sensor hardware defect less common

Safe checks you can do yourself

Disconnect all wires from the charger, then reconnect them firmly to trigger a restart.
Check input and output terminals for loose or corroded connections.

How to reset / clear Error 21

Disconnect and reconnect all wiring to restart the unit.
If the error returns after a clean reconnection, the unit likely has a hardware fault.

When to call a technician

If error 21 persists after disconnecting and reconnecting all wiring, contact your Victron dealer; this typically indicates a hardware defect.

Applies to

Orion XS 12/12-50A DC-DC charger

FAQ

What does Victron Energy Power Converter code "Error 21" mean?

Current sensor problem. The measured charge current is out of the expected range, suggesting a current-measurement fault. This error does not clear by itself.

How do I reset Victron Energy Power Converter Error 21?

Disconnect and reconnect all wiring to restart the unit. If the error returns after a clean reconnection, the unit likely has a hardware fault.

What is the most common cause of Error 21 on a Victron Energy Power Converter?

The most likely cause is transient wiring/connection issue affecting current measurement.

Related · Victron Energy power converter

Error 1
Battery temperature too high. The charger halts charging to … Error 26
Terminal overheated. The power terminals are running too hot… Error 33
Input voltage too high. The DC input voltage feeding the cha… Error 67
The charger is set to be controlled by a battery BMS but is … Error 119
Settings data lost. The charger cannot read its stored confi…

Sources

Orion XS 12/12-50A DC-DC battery charger - Troubleshooting & Support — Section 5, Error 21 - Current sensor issue (Victron Energy)

Note: Confirmed for the Orion XS troubleshooting documentation.

● Last verified 2026-06-29 · compiled from manufacturer documentation. Codes can vary by model year — always cross-check your unit’s manual.