Inverter fault codes, explained.

The cooling fan is running its start-up check.

1. Clears on its own.
2. If it keeps appearing, clean dust from the fan and vents.

The inverter is running hotter than its safe limit, or the temperature sensor lost contact.

1. Switch the inverter off and let it cool for 30 minutes.
2. Leave at least 20 cm clear on every side.
3. Never install in a sealed cupboard or in direct sunlight.

Charging voltage is set too high for the battery, or the BMS link is missing.

1. Check the charge settings: lithium 56.4–57.6 V, AGM 12 V float 13.6–13.8 V.
2. Confirm the battery type is set correctly in the inverter menu.
3. On lithium, check the BMS communication cable is seated.

The bank has been drawn down further than it should be.

1. Reduce the load now.
2. Charge from solar or AC.
3. Never take AGM below 50 % — repeated deep discharge permanently shortens its life.

More load is connected than the inverter is rated for. The alarm beeps twice a second.

1. Switch off heavy appliances immediately — iron, water pump, washing machine.
2. Add the wattage of everything running and compare it with the inverter's rating.
3. Reconnect one appliance at a time, smallest first.

The inverter is deliberately reducing output to protect itself, usually from heat.

1. Reduce the load.
2. Improve ventilation.
3. It recovers by itself once cooler.

Little or no power is arriving from the panels.

1. Clean the panels.
2. Check for shade from trees, walls or a water tank.
3. Check the MC4 connectors are fully clicked together.
4. Normal in cloud, or early morning and late afternoon.

The grid or generator is supplying above the accepted range.

1. On a generator, check the AVR.
2. On grid, wait for the supply to stabilise.

The inverter cannot read the solar current correctly.

1. Check the PV cable connections for damage.
2. Contact support if it persists.

The inverter cannot see the battery bank at all.

1. Check the cables, the fuse and the terminals for corrosion.
2. On lithium, press the battery's ON button.
3. Check the DC breaker is closed.

A scheduled conditioning charge is running.

1. Normal for AGM — let it finish.
2. Disable equalisation in settings when using lithium.

The cooling fan did not start correctly.

1. Switch off and check the fan spins freely.
2. Clean out dust.
3. A failed fan must be replaced professionally.

The unit reached a dangerous temperature, or the sensor failed.

1. Switch off at once and let it cool for an hour.
2. Check ventilation and clearance.
3. If the temperature is normal but the fault stays, the sensor needs a technician.

Battery voltage exceeded the inverter's safe ceiling.

1. Switch off and disconnect the battery to reset.
2. Lithium 48 V: maximum 58.4 V. AGM 48 V: maximum 57.6 V.
3. Check the charge settings before reconnecting.

The bank fell below the level the inverter can work with.

1. Charge from AC immediately.
2. AGM left at very low voltage for long is permanently damaged.

A short was detected on the output wiring or an appliance.

1. Switch off and disconnect every appliance.
2. Check the output wiring for damage.
3. If no short is found, contact support — do not keep restarting.

The inverter produced a higher output voltage than it should.

1. Switch off and restart with no load connected.
2. If it repeats, it needs professional service.

The overload was large enough to trip a protective shutdown.

1. Switch off every appliance.
2. Wait 30 seconds and restart.
3. Reconnect one at a time, smallest first.

Internal DC voltage rose above its limit.

1. Switch off, wait one minute, restart.
2. Contact support if it repeats.

The inverter could not bring its internal bus up to voltage.

1. Switch off and wait two minutes.
2. Check the battery connections.
3. If the bank is very low, charge from AC first.

The output current regulation did not behave as expected.

1. Restart.
2. Contact support if it returns.

Internal DC voltage stayed below the working range.

1. Check battery voltage and connections.
2. Restart.

The output could not start up cleanly, usually because of load.

1. Disconnect all loads and restart.
2. Reconnect one appliance at a time.

Too much DC content was measured on the AC output.

1. Restart.
2. If it recurs, contact support.

An internal current sensor failed its check.

1. Restart.
2. Persistent failures need professional repair.

Output voltage is below the accepted band.

1. Reduce the load.
2. If it stays low with nothing connected, it needs service.

Too many panels in series — string voltage exceeds the inverter's limit.

1. Disconnect the solar panels immediately.
2. Recalculate string open-circuit voltage at the coldest expected temperature.
3. Rewire the strings shorter before reconnecting.

Power is flowing between units instead of to the load.

1. Check load balance.
2. Confirm all units are the same model.
3. Restart every unit.

The units are running different firmware.

1. All units need the same firmware version — contact support.

The units cannot agree on how to split the load.

1. Check the communication cables.
2. Restart all units.

Units are set to different output voltages.

1. Match the output voltage on every unit — 220, 230 or 240 V.

The parallel data link between units is broken.

1. Unplug and refit the parallel cable firmly.
2. Replace the cable if damaged.

The slave units cannot hear the master.

1. Power the MASTER unit first.
2. Check the cable to the first slave.

The units lost synchronisation with each other.

1. Switch off all units.
2. Check every cable.
3. Power the MASTER first, then each slave 30 seconds apart.

The banks on each unit are at different states of charge.

1. Charge all banks to the same voltage first.
2. Never mix old and new batteries.

Units are seeing different AC input.

1. All units must share one AC source, with the same cable length and gauge.

One unit is carrying more of the load than the others.

1. Use equal cable lengths and gauges on all outputs.
2. Check the communication cable.

The units are configured differently.

1. Match on every unit: battery type, charge current, output voltage, operating mode and low-battery cutoff.

The inverter cannot talk to the lithium battery's management system.

1. Check the BMS cable between inverter and battery.
2. Confirm the battery is switched on.
3. Refit the cable firmly at both ends.
4. Set the inverter's battery type to LITHIUM.

The battery is outside its safe temperature range, or the sensor failed.

1. Above 50 °C: move it somewhere cooler and ventilated.
2. Below −10 °C: warm the space before charging.
3. If the temperature is normal, contact support.

The BMS is refusing charge — full, too hot, too cold, or cells out of balance.

1. Check the battery LEDs.
2. If it is not full and the temperature is normal, let it rest 30 minutes.
3. Persistent refusal points to cell imbalance — contact support.

The pack is critically low and has protected itself.

1. Charge from AC or solar now.
2. Never bypass BMS protection.