The Complete Guide To Redback Inverter Error Codes

The grid frequency went outside the inverter's limits for a moment and it disconnected. This is a grid event, not an inverter fault; it reconnects by itself once the grid is steady.

On a house with two or three SI Smart Inverters on different phases, a fault on one makes the others disconnect from the grid until it recovers or is isolated. The healthy inverters show a grid-disconnect pattern; the faulted one shows red. Restarting the faulted unit usually brings the set back; if it will not restart, the installer isolates it so the others can run. A protection lockout means the inverter found something it will not run with, so we treat it as a call.

The inverter has stopped on a fault it does not name on the panel: the SYSTEM ERROR LED is on steadily with no beeping (on the SI the status LED is solid red). Redback says many are caused by outside factors such as grid quality and clear within ten minutes; if not, one restart is next, and if it comes back it needs Redback or your installer. The portal and the alarm email name the fault.

The inverter cannot see mains power on its grid side. Usually the power is out, or the solar supply main switch or the UTILITY GRID isolator is off. On a hybrid the backup circuit keeps running from solar and battery; the inverter reconnects itself about a minute after the grid is back.

The mains voltage at the inverter went outside the range it is allowed to connect at, so it disconnected from the grid as the rules require. On the SH5000, SI and ST this shows as the UTILITY GRID LED flashing (grid active but not connected). It reconnects by itself; if it happens most sunny afternoons the street voltage or the cable run needs checking.

The appliances on the backup circuit are drawing more than the inverter can supply: on the SH5000 more than 4.6 kW continuously, 6.9 kW for ten seconds, or more than the solar and battery can give during a blackout. The SYSTEM ERROR LED flashes and the inverter shuts down, then retries about a minute later. Switch off the heavy appliances and it recovers.

The inverter is not able to run the backup circuit from the battery: the BACKUP POWER LED is off. Shortly after a restart this is normal for up to ten minutes; otherwise the battery is flat, switched off or not communicating, and the backup circuit will not carry the house through a blackout until it is fixed.

The voltage from the solar panels is above what the inverter accepts, which usually means too many panels in one string. It shows most on cold clear mornings. The string design needs checking by an electrician; the inverter protects itself by not starting. Over-voltage, over-current and short-circuit faults can damage hardware, so we treat them as a call.

The inverter is not seeing any power from the panels in daylight: the SOLAR ARRAY LED is off, or one of the two arrays shows Not Active when both are installed. Most often the PV ARRAY DC isolator is off; at night both arrays showing Not Active is normal. If the isolator is on and it is daylight, a string or isolator fault needs an electrician.

The system has detected an earth fault on the solar or battery wiring. After one minute the inverter sounds an audible alarm, the SYSTEM ERROR LED (or SYSTEM icon) turns solid red, and Redback emails its support team, the installer and the owner, with another email when it clears. It is an electrical safety fault: contact your installer as soon as possible rather than restarting it.

The inverter's own earth-leakage sensing circuit has failed its check, as opposed to finding a real leak. If one restart does not clear it the sensor or board inside has failed and needs a technician.

The inverter measured current leaking to earth from the solar or battery wiring, usually damaged insulation, water in a connector or a wet rooftop isolator. Because this is an electrical safety trip, do not keep restarting it; a repeat needs an electrician.

The inverter found too little insulation between the solar wiring and earth, usually water in a connector or rooftop isolator, a chafed cable or a damaged panel. Morning alarms that clear by midday point to dew; a fault that stays is an electrical safety issue and needs an electrician.

The sensor the inverter uses to measure its own output current failed its self-check, so the inverter cannot trust its readings and stops. One restart may clear it; if it comes back the sensor or board inside has failed.

The voltage on the inverter's internal DC bus went above its limit. It can be a string with too many panels or a surge; if a restart does not clear it the power board inside needs a technician.

The inverter is letting a small amount of DC into its AC output, which the grid rules do not allow, so it disconnected. A one-off usually clears with a wait or one restart; if it keeps coming back the output stage or its current sensor needs testing. DC on the AC side is a protection fault, so we treat it as a call.

The inverter could not read or write its settings memory. It usually keeps producing, and one restart often clears it; if it comes back the control board has a fault and the settings may need reloading by a technician. Internal and hardware faults need testing with the right instruments, so we treat them as a call.

The EMS, the small control computer inside the switchgear box that runs the inverter and its monitoring, has frozen, is mid-update or has lost its link to the inverter. The HEARTBEAT LED stops flashing or the INVERTER LED goes off. Redback's guide says wait five minutes, then an EMS restart; the EMS restart should only be done when Redback support or the guide's LED table asks for it.

The inverter shows no life even though the grid and solar are on: on the SI the status LED stays off, on the SH5000 the SYSTEM READY LED stays off for more than a minute after a restart. If the isolators are on and the house has power, Redback calls this an internal failure and it needs Redback or your installer.

The relays that connect the inverter to the grid failed their self-test, which usually means a relay is stuck or welded. The inverter must not keep running on a failed relay, so if one restart does not clear it the unit needs a technician.

The processors inside the inverter have stopped talking to each other. This is not the wifi or app connection. It can recover with one restart; if it comes back the control board needs a technician.

The inverter's internal temperature went over its limit, so it cut back or shut down. Redback cuts output above 45 degrees inside and shuts down above 60. Usually it is in full sun, a closed room or a hot shed; it comes back once it cools. If it happens on ordinary days the mounting spot or the cooling fins need a look. Heat shutdowns point at a failing fan, a blocked vent or a bad installation spot, so we treat them as a call.

The battery's management system reports that the cells inside a module are at different voltages. A small spread often settles after a full charge; a large or growing spread means a weak module that the installer or battery maker needs to assess.

The inverter tried to push more charge current into the battery than the battery maker allows. It usually clears on its own; if it repeats the charge rate setting or a battery module needs checking by the installer. Over-voltage, over-current and short-circuit faults can damage hardware, so we treat them as a call.

The inverter has lost contact with the battery's management system (BMS), so it will not charge or discharge the battery until it is back. Often a module has switched itself off, a comms cable is loose, or the EMS needs a restart. On the SH5000 the EMS BATTERY LED shows a battery detection error; the owner's guide says to restart the EMS.

The backup circuit was pulling more current from the battery than the battery maker allows, usually a large appliance starting during a blackout. Switch off the heavy appliance and it recovers; if it trips with ordinary loads the settings need checking. Over-voltage, over-current and short-circuit faults can damage hardware, so we treat them as a call.

The battery's management system detected a short circuit on its output. This is a serious DC fault: leave the battery isolators where they are and call your installer; do not keep restarting it.

The battery modules in the enclosure are above their safe temperature, so the inverter has stopped charging and discharging them. It restarts once they cool; if it happens on ordinary days the enclosure's ventilation or location needs a look, and a battery that heats up at rest needs an electrician. Heat shutdowns point at a failing fan, a blocked vent or a bad installation spot, so we treat them as a call.

The battery bank's total voltage went above the limit the battery maker sets, so the inverter stopped charging it. A one-off at the end of a charge usually clears; a repeat means the charge settings or a battery module need checking.

The battery has reached its minimum state of charge and the inverter has stopped drawing from it to protect it. This is normal protection, not a fault: on the SH5000 the BATTERY LED double-flashes until it recharges from solar or the grid. If it stays low on a sunny day the charge settings need a look.

The battery modules are below the temperature the battery maker allows for charging, so the inverter has paused charging to protect them. This is normal on frosty mornings in a cold shed or garage and clears as the day warms.

The battery bank's total voltage has dropped below the battery maker's minimum, usually after a long blackout or a long cloudy stretch with heavy backup use. The inverter stops drawing from it to protect it. It should recover once solar or the grid recharges it; a battery that will not recharge needs the installer.

The inverter has lost its internet connection, so the portal and MyRedback app stop updating and Redback cannot send alarm emails. The system keeps producing. Nearly always a router, wifi password or network change; Redback says the inverter does not work on 5 GHz wifi. Ethernet systems usually recover after a restart; wifi systems need re-onboarding with the app.

The Redback smart meter at the switchboard (PA110 on the SI, SM3000 on the SH5000, SB and ST) has stopped sending the house's import and export figures to the inverter. The inverter keeps producing but cannot see the house load, so the battery and export control go wrong. Redback says to contact your installer straight away.