SAJ H2 hybrid inverter error codes and what they mean
SAJ H2 hybrid inverters show a numeric error code in the eSAJ Home app (and the LED ring turns red for serious faults). SAJ's manual lists the code names and asks owners to contact after-sales support for any of them, so the explanations below are general guidance on what each name indicates.
Safety first, please read
- Solar panels and batteries produce dangerous DC voltage whenever there is daylight or charge in the battery, even with the mains switched off. Electrical work on these systems must only be done by a licensed electrician.
- Never open the inverter or battery, and don't unplug, touch or adjust DC cables, connectors or isolators except for the owner shutdown steps in your manufacturer's manual.
- For an isolation/insulation fault, earth fault, arc fault, residual-current fault or battery over-temperature alarm, or any smoke, burning smell, hissing, swelling, leaking or water damage: only switch off if the manufacturer's procedure lets you do it safely, keep everyone clear, and call a licensed electrician or Total Solar.
- If there is fire or smoke, get everyone out and call 000. Tell the fire service there is a solar and battery system on site.
- Don't climb on the roof to check or clean panels. Do checks from the ground only.
Owner shutdown and restart (SAJ)
SAJ's H2 manual gives this manual shutdown order: turn off the inverter's DC (PV) switch, then the battery switch, then the AC circuit breaker. Only do this if your installer has shown you how and it is safe.
H2 hybrid series (H2-S2 single-phase / H2-T2 three-phase, AU) (83 codes)
1Master Relay ErrorFault
What it means: The equipment's self-checks found an internal problem (for example relays, measuring circuits, internal communication or power electronics). Some of these clear by themselves after a one-off event, but repeated alarms usually need a technician.
Likely causes:
- A one-off disturbance (for example a grid event)
- Internal component or circuit board fault
- Firmware issue
What you can safely do:
- Note the code, time and whether it clears by itself
- If your installer showed you the owner shutdown/restart procedure from the manufacturer's manual (summarised at the top of this page), you may restart the system once. Do not open covers or touch cabling.
- If the code returns or the system stays offline, call us. Internal faults are a warranty/technician job
2Master EEPROM ErrorFault
What it means: The equipment's self-checks found an internal problem (for example relays, measuring circuits, internal communication or power electronics). Some of these clear by themselves after a one-off event, but repeated alarms usually need a technician.
Likely causes:
- A one-off disturbance (for example a grid event)
- Internal component or circuit board fault
- Firmware issue
What you can safely do:
- Note the code, time and whether it clears by itself
- If your installer showed you the owner shutdown/restart procedure from the manufacturer's manual (summarised at the top of this page), you may restart the system once. Do not open covers or touch cabling.
- If the code returns or the system stays offline, call us. Internal faults are a warranty/technician job
3Master Temperature High ErrorWarning
What it means: The inverter is running too hot, so it has reduced output or paused to protect itself.
Likely causes:
- High ambient temperature or direct afternoon sun on the inverter
- Blocked air vents or heat sink (dust, cobwebs, stored items)
- A fan problem (on fan-cooled models)
What you can safely do:
- Make sure nothing is stacked against or in front of the inverter, and leave the manufacturer's clearances around it
- Gently clear dust or leaves from the outside of the vents, without opening the unit or spraying water
- Let it cool. It normally resumes by itself
- If it keeps happening on mild days, call us
4Master Temperature Low ErrorWarning
What it means: The inverter temperature is below its operating range.
Likely causes:
- Very cold ambient conditions
What you can safely do:
- Wait for temperatures to rise. It should recover by itself
- If it persists in normal weather, call us
5Lost Communication M<->SFault
What it means: The equipment's self-checks found an internal problem (for example relays, measuring circuits, internal communication or power electronics). Some of these clear by themselves after a one-off event, but repeated alarms usually need a technician.
Likely causes:
- A one-off disturbance (for example a grid event)
- Internal component or circuit board fault
- Firmware issue
What you can safely do:
- Note the code, time and whether it clears by itself
- If your installer showed you the owner shutdown/restart procedure from the manufacturer's manual (summarised at the top of this page), you may restart the system once. Do not open covers or touch cabling.
- If the code returns or the system stays offline, call us. Internal faults are a warranty/technician job
6GFCI Device ErrorFault
What it means: The equipment's self-checks found an internal problem (for example relays, measuring circuits, internal communication or power electronics). Some of these clear by themselves after a one-off event, but repeated alarms usually need a technician.
Likely causes:
- A one-off disturbance (for example a grid event)
- Internal component or circuit board fault
- Firmware issue
What you can safely do:
- Note the code, time and whether it clears by itself
- If your installer showed you the owner shutdown/restart procedure from the manufacturer's manual (summarised at the top of this page), you may restart the system once. Do not open covers or touch cabling.
- If the code returns or the system stays offline, call us. Internal faults are a warranty/technician job
7DCI Device ErrorFault
What it means: The equipment's self-checks found an internal problem (for example relays, measuring circuits, internal communication or power electronics). Some of these clear by themselves after a one-off event, but repeated alarms usually need a technician.
Likely causes:
- A one-off disturbance (for example a grid event)
- Internal component or circuit board fault
- Firmware issue
What you can safely do:
- Note the code, time and whether it clears by itself
- If your installer showed you the owner shutdown/restart procedure from the manufacturer's manual (summarised at the top of this page), you may restart the system once. Do not open covers or touch cabling.
- If the code returns or the system stays offline, call us. Internal faults are a warranty/technician job
8Current Sensor ErrorFault
What it means: The equipment's self-checks found an internal problem (for example relays, measuring circuits, internal communication or power electronics). Some of these clear by themselves after a one-off event, but repeated alarms usually need a technician.
Likely causes:
- A one-off disturbance (for example a grid event)
- Internal component or circuit board fault
- Firmware issue
What you can safely do:
- Note the code, time and whether it clears by itself
- If your installer showed you the owner shutdown/restart procedure from the manufacturer's manual (summarised at the top of this page), you may restart the system once. Do not open covers or touch cabling.
- If the code returns or the system stays offline, call us. Internal faults are a warranty/technician job
9Master Phase1 Voltage HighWarning
What it means: The mains voltage the inverter measured was outside the limits allowed for your network, so it disconnected or reduced output to protect the grid. This is usually a grid condition, not a faulty inverter.
Likely causes:
- High street voltage, common on sunny afternoons when many homes export solar
- Grid disturbances or voltage dips
- Long or undersized AC cabling between the inverter and the switchboard (installation issue)
- Grid protection settings that don't match your network's requirements
What you can safely do:
- Wait. The inverter reconnects by itself once voltage is back within limits
- Note the time of day it happens. If it happens most sunny days, tell us, because it may need a voltage check or a report to your network operator
- Don't try to change grid protection settings yourself. In Australia they are set to AS/NZS 4777.2 and your network operator's requirements
10Master Phase1 Voltage LowWarning
What it means: The mains voltage the inverter measured was outside the limits allowed for your network, so it disconnected or reduced output to protect the grid. This is usually a grid condition, not a faulty inverter.
Likely causes:
- High street voltage, common on sunny afternoons when many homes export solar
- Grid disturbances or voltage dips
- Long or undersized AC cabling between the inverter and the switchboard (installation issue)
- Grid protection settings that don't match your network's requirements
What you can safely do:
- Wait. The inverter reconnects by itself once voltage is back within limits
- Note the time of day it happens. If it happens most sunny days, tell us, because it may need a voltage check or a report to your network operator
- Don't try to change grid protection settings yourself. In Australia they are set to AS/NZS 4777.2 and your network operator's requirements
11Master Phase2 Voltage HighWarning
What it means: The mains voltage the inverter measured was outside the limits allowed for your network, so it disconnected or reduced output to protect the grid. This is usually a grid condition, not a faulty inverter. (Phase 2/3 codes apply to three-phase models.)
Likely causes:
- High street voltage, common on sunny afternoons when many homes export solar
- Grid disturbances or voltage dips
- Long or undersized AC cabling between the inverter and the switchboard (installation issue)
- Grid protection settings that don't match your network's requirements
What you can safely do:
- Wait. The inverter reconnects by itself once voltage is back within limits
- Note the time of day it happens. If it happens most sunny days, tell us, because it may need a voltage check or a report to your network operator
- Don't try to change grid protection settings yourself. In Australia they are set to AS/NZS 4777.2 and your network operator's requirements
12Master Phase2 Voltage LowWarning
What it means: The mains voltage the inverter measured was outside the limits allowed for your network, so it disconnected or reduced output to protect the grid. This is usually a grid condition, not a faulty inverter. (Phase 2/3 codes apply to three-phase models.)
Likely causes:
- High street voltage, common on sunny afternoons when many homes export solar
- Grid disturbances or voltage dips
- Long or undersized AC cabling between the inverter and the switchboard (installation issue)
- Grid protection settings that don't match your network's requirements
What you can safely do:
- Wait. The inverter reconnects by itself once voltage is back within limits
- Note the time of day it happens. If it happens most sunny days, tell us, because it may need a voltage check or a report to your network operator
- Don't try to change grid protection settings yourself. In Australia they are set to AS/NZS 4777.2 and your network operator's requirements
13Master Phase3 Voltage HighWarning
What it means: The mains voltage the inverter measured was outside the limits allowed for your network, so it disconnected or reduced output to protect the grid. This is usually a grid condition, not a faulty inverter. (Phase 2/3 codes apply to three-phase models.)
Likely causes:
- High street voltage, common on sunny afternoons when many homes export solar
- Grid disturbances or voltage dips
- Long or undersized AC cabling between the inverter and the switchboard (installation issue)
- Grid protection settings that don't match your network's requirements
What you can safely do:
- Wait. The inverter reconnects by itself once voltage is back within limits
- Note the time of day it happens. If it happens most sunny days, tell us, because it may need a voltage check or a report to your network operator
- Don't try to change grid protection settings yourself. In Australia they are set to AS/NZS 4777.2 and your network operator's requirements
14Master Phase3 Voltage LowWarning
What it means: The mains voltage the inverter measured was outside the limits allowed for your network, so it disconnected or reduced output to protect the grid. This is usually a grid condition, not a faulty inverter. (Phase 2/3 codes apply to three-phase models.)
Likely causes:
- High street voltage, common on sunny afternoons when many homes export solar
- Grid disturbances or voltage dips
- Long or undersized AC cabling between the inverter and the switchboard (installation issue)
- Grid protection settings that don't match your network's requirements
What you can safely do:
- Wait. The inverter reconnects by itself once voltage is back within limits
- Note the time of day it happens. If it happens most sunny days, tell us, because it may need a voltage check or a report to your network operator
- Don't try to change grid protection settings yourself. In Australia they are set to AS/NZS 4777.2 and your network operator's requirements
15Grid Voltage 10Min HighWarning
What it means: The mains voltage the inverter measured was outside the limits allowed for your network, so it disconnected or reduced output to protect the grid. This is usually a grid condition, not a faulty inverter.
Likely causes:
- High street voltage, common on sunny afternoons when many homes export solar
- Grid disturbances or voltage dips
- Long or undersized AC cabling between the inverter and the switchboard (installation issue)
- Grid protection settings that don't match your network's requirements
What you can safely do:
- Wait. The inverter reconnects by itself once voltage is back within limits
- Note the time of day it happens. If it happens most sunny days, tell us, because it may need a voltage check or a report to your network operator
- Don't try to change grid protection settings yourself. In Australia they are set to AS/NZS 4777.2 and your network operator's requirements
16OffGrid Output Voltage LowWarning
What it means: The backup/EPS (off-grid) output is overloaded or abnormal, so the system has limited or switched off backup power.
Likely causes:
- Too many or too large appliances on backup circuits during an outage (for example ovens, air conditioners, pumps)
- High start-up surge from motors or compressors
- A short circuit on a backup circuit
What you can safely do:
- Switch off large appliances on backup circuits
- Wait for the system to retry (some models lock out for a period after repeated overloads)
- If it trips with only small loads on, or you suspect a short circuit, call an electrician
17OffGrid Output Short CircuitWarning
What it means: The backup/EPS (off-grid) output is overloaded or abnormal, so the system has limited or switched off backup power.
Likely causes:
- Too many or too large appliances on backup circuits during an outage (for example ovens, air conditioners, pumps)
- High start-up surge from motors or compressors
- A short circuit on a backup circuit
What you can safely do:
- Switch off large appliances on backup circuits
- Wait for the system to retry (some models lock out for a period after repeated overloads)
- If it trips with only small loads on, or you suspect a short circuit, call an electrician
18Master Grid Frequency HighWarning
What it means: Grid frequency moved outside the allowed range, so the inverter disconnected or reduced output as the standards require.
Likely causes:
- Short grid disturbance
- Running on a generator or a weak supply
- Grid settings that don't match the local network
What you can safely do:
- Wait for automatic reconnection
- If it happens often, record the times and contact us
19Master Grid Frequency LowWarning
What it means: Grid frequency moved outside the allowed range, so the inverter disconnected or reduced output as the standards require.
Likely causes:
- Short grid disturbance
- Running on a generator or a weak supply
- Grid settings that don't match the local network
What you can safely do:
- Wait for automatic reconnection
- If it happens often, record the times and contact us
21Phase1 DCV ErrorFault
What it means: The inverter detected too much DC current in its AC output, which the grid standards don't allow, so it disconnected.
Likely causes:
- A one-off disturbance (if it is occasional)
- Internal measuring or power stage problem (if it repeats)
What you can safely do:
- If it happened once and the system recovered, keep an eye on it
- If it repeats, call us
22Phase2 DCV ErrorFault
What it means: The inverter detected too much DC current in its AC output, which the grid standards don't allow, so it disconnected. (Phase 2/3 codes apply to three-phase models.)
Likely causes:
- A one-off disturbance (if it is occasional)
- Internal measuring or power stage problem (if it repeats)
What you can safely do:
- If it happened once and the system recovered, keep an eye on it
- If it repeats, call us
23Phase3 DCV ErrorFault
What it means: The inverter detected too much DC current in its AC output, which the grid standards don't allow, so it disconnected. (Phase 2/3 codes apply to three-phase models.)
Likely causes:
- A one-off disturbance (if it is occasional)
- Internal measuring or power stage problem (if it repeats)
What you can safely do:
- If it happened once and the system recovered, keep an eye on it
- If it repeats, call us
24Master No Grid ErrorWarning
What it means: The inverter cannot see a normal mains supply, so it has stopped exporting to the grid (and a hybrid system may switch to backup).
Likely causes:
- Power outage in your street or area
- A tripped or switched-off solar/inverter circuit breaker in the switchboard
- Loose AC connection between the switchboard and the inverter
What you can safely do:
- Check whether the rest of the house (or your neighbours) has power, and check your network operator's outage map
- Check the switchboard for a tripped solar supply main switch or inverter breaker. Only reset it once. If it trips again, leave it off and call an electrician
- Wait. Once normal grid power is back, the inverter normally reconnects by itself after its safety checks (often a few minutes)
- If grid power is normal but the alarm stays, call us
27GFCI ErrorSafety-critical
What it means: The inverter measured leakage (residual) current flowing to earth above its safety limit and disconnected. This can indicate damaged insulation somewhere in the system.
Likely causes:
- Damaged DC or AC cable insulation
- Moisture in connectors or equipment
- A one-off disturbance (if it happens once and never again)
What you can safely do:
- Don't touch cabling or equipment
- If it happens repeatedly, or together with an insulation/isolation alarm, call an electrician or us promptly
28Phase1 DCI ErrorFault
What it means: The inverter detected too much DC current in its AC output, which the grid standards don't allow, so it disconnected.
Likely causes:
- A one-off disturbance (if it is occasional)
- Internal measuring or power stage problem (if it repeats)
What you can safely do:
- If it happened once and the system recovered, keep an eye on it
- If it repeats, call us
29Phase2 DCI ErrorFault
What it means: The inverter detected too much DC current in its AC output, which the grid standards don't allow, so it disconnected. (Phase 2/3 codes apply to three-phase models.)
Likely causes:
- A one-off disturbance (if it is occasional)
- Internal measuring or power stage problem (if it repeats)
What you can safely do:
- If it happened once and the system recovered, keep an eye on it
- If it repeats, call us
30Phase3 DCI ErrorFault
What it means: The inverter detected too much DC current in its AC output, which the grid standards don't allow, so it disconnected. (Phase 2/3 codes apply to three-phase models.)
Likely causes:
- A one-off disturbance (if it is occasional)
- Internal measuring or power stage problem (if it repeats)
What you can safely do:
- If it happened once and the system recovered, keep an eye on it
- If it repeats, call us
31ISO ErrorSafety-critical
What it means: Insulation resistance between the solar circuits and earth is too low. SAJ notes that on this model an earth fault alarm turns the LED ring red and shows error <31> in the eSAJ Home app.
Likely causes:
- Damaged DC cable insulation (for example from rodents, UV or a pinched cable)
- Water in a DC connector, isolator or junction box
- A damaged solar panel or backsheet
- Heavy dew or rain can trigger it temporarily on marginal systems
What you can safely do:
- Do not touch panels, DC cables, rooftop isolators or the inverter's DC connectors
- If it clears by itself after the weather dries out, still report it, because repeated alarms point to a developing fault
- Book an electrician or call us. An insulation test needs specialist equipment
- If you see smoke, burn marks or smell burning, keep clear and call 000
32Bus Voltage Balance ErrorFault
What it means: The equipment's self-checks found an internal problem (for example relays, measuring circuits, internal communication or power electronics). Some of these clear by themselves after a one-off event, but repeated alarms usually need a technician.
Likely causes:
- A one-off disturbance (for example a grid event)
- Internal component or circuit board fault
- Firmware issue
What you can safely do:
- Note the code, time and whether it clears by itself
- If your installer showed you the owner shutdown/restart procedure from the manufacturer's manual (summarised at the top of this page), you may restart the system once. Do not open covers or touch cabling.
- If the code returns or the system stays offline, call us. Internal faults are a warranty/technician job
33Master Bus Voltage HighFault
What it means: The equipment's self-checks found an internal problem (for example relays, measuring circuits, internal communication or power electronics). Some of these clear by themselves after a one-off event, but repeated alarms usually need a technician.
Likely causes:
- A one-off disturbance (for example a grid event)
- Internal component or circuit board fault
- Firmware issue
What you can safely do:
- Note the code, time and whether it clears by itself
- If your installer showed you the owner shutdown/restart procedure from the manufacturer's manual (summarised at the top of this page), you may restart the system once. Do not open covers or touch cabling.
- If the code returns or the system stays offline, call us. Internal faults are a warranty/technician job
34Master Bus Voltage LowFault
What it means: The equipment's self-checks found an internal problem (for example relays, measuring circuits, internal communication or power electronics). Some of these clear by themselves after a one-off event, but repeated alarms usually need a technician.
Likely causes:
- A one-off disturbance (for example a grid event)
- Internal component or circuit board fault
- Firmware issue
What you can safely do:
- Note the code, time and whether it clears by itself
- If your installer showed you the owner shutdown/restart procedure from the manufacturer's manual (summarised at the top of this page), you may restart the system once. Do not open covers or touch cabling.
- If the code returns or the system stays offline, call us. Internal faults are a warranty/technician job
35Master Grid Phase ErrorWarning
What it means: The inverter saw something abnormal about the grid supply (for example phase loss, imbalance, waveform distortion or loss of mains), so it disconnected as a safety measure.
Likely causes:
- Grid disturbance or partial outage (for example one phase lost on a 3-phase supply)
- Supply problems on the network side
- Wiring or phase-order errors at installation (if it shows up from day one)
What you can safely do:
- Check whether you have a partial power outage (some circuits or phases off)
- Wait for automatic reconnection after the grid returns to normal
- If it persists or started after electrical work, call us
36Master PV Voltage High ErrorFault
What it means: The DC voltage coming from the solar panels is higher than the inverter is rated for. Over-voltage can damage the inverter.
Likely causes:
- Too many panels wired in series in a string (system design/installation issue)
- Very cold, bright mornings raise panel voltage
- Incorrect panel or string configuration after a change to the system
What you can safely do:
- Do not touch the DC isolator or cables unless the manufacturer's owner shutdown tells you to
- Call us. The string design needs to be checked by a licensed installer
37Master Islanding ErrorWarning
What it means: The inverter saw something abnormal about the grid supply (for example phase loss, imbalance, waveform distortion or loss of mains), so it disconnected as a safety measure.
Likely causes:
- Grid disturbance or partial outage (for example one phase lost on a 3-phase supply)
- Supply problems on the network side
- Wiring or phase-order errors at installation (if it shows up from day one)
What you can safely do:
- Check whether you have a partial power outage (some circuits or phases off)
- Wait for automatic reconnection after the grid returns to normal
- If it persists or started after electrical work, call us
38Master HW Bus Voltage HighFault
What it means: The equipment's self-checks found an internal problem (for example relays, measuring circuits, internal communication or power electronics). Some of these clear by themselves after a one-off event, but repeated alarms usually need a technician.
Likely causes:
- A one-off disturbance (for example a grid event)
- Internal component or circuit board fault
- Firmware issue
What you can safely do:
- Note the code, time and whether it clears by itself
- If your installer showed you the owner shutdown/restart procedure from the manufacturer's manual (summarised at the top of this page), you may restart the system once. Do not open covers or touch cabling.
- If the code returns or the system stays offline, call us. Internal faults are a warranty/technician job
39Master HW PV Current HighFault
What it means: The equipment's self-checks found an internal problem (for example relays, measuring circuits, internal communication or power electronics). Some of these clear by themselves after a one-off event, but repeated alarms usually need a technician.
Likely causes:
- A one-off disturbance (for example a grid event)
- Internal component or circuit board fault
- Firmware issue
What you can safely do:
- Note the code, time and whether it clears by itself
- If your installer showed you the owner shutdown/restart procedure from the manufacturer's manual (summarised at the top of this page), you may restart the system once. Do not open covers or touch cabling.
- If the code returns or the system stays offline, call us. Internal faults are a warranty/technician job
40Master Self-Test FailedFault
What it means: The equipment's self-checks found an internal problem (for example relays, measuring circuits, internal communication or power electronics). Some of these clear by themselves after a one-off event, but repeated alarms usually need a technician.
Likely causes:
- A one-off disturbance (for example a grid event)
- Internal component or circuit board fault
- Firmware issue
What you can safely do:
- Note the code, time and whether it clears by itself
- If your installer showed you the owner shutdown/restart procedure from the manufacturer's manual (summarised at the top of this page), you may restart the system once. Do not open covers or touch cabling.
- If the code returns or the system stays offline, call us. Internal faults are a warranty/technician job
41HW Inv Current HighFault
What it means: The equipment's self-checks found an internal problem (for example relays, measuring circuits, internal communication or power electronics). Some of these clear by themselves after a one-off event, but repeated alarms usually need a technician.
Likely causes:
- A one-off disturbance (for example a grid event)
- Internal component or circuit board fault
- Firmware issue
What you can safely do:
- Note the code, time and whether it clears by itself
- If your installer showed you the owner shutdown/restart procedure from the manufacturer's manual (summarised at the top of this page), you may restart the system once. Do not open covers or touch cabling.
- If the code returns or the system stays offline, call us. Internal faults are a warranty/technician job
42Master AC SPD ErrorFault
What it means: A surge protection device (SPD) inside or connected to the inverter is reporting a fault, often after a lightning storm or grid surge.
Likely causes:
- SPD has done its job after a surge and now needs replacing
- SPD wiring fault
What you can safely do:
- Don't open the inverter
- Call us. SPDs must be replaced by a licensed electrician
43Master DC SPD ErrorFault
What it means: A surge protection device (SPD) inside or connected to the inverter is reporting a fault, often after a lightning storm or grid surge.
Likely causes:
- SPD has done its job after a surge and now needs replacing
- SPD wiring fault
What you can safely do:
- Don't open the inverter
- Call us. SPDs must be replaced by a licensed electrician
44Master Grid NE Voltage ErrorSafety-critical
What it means: The inverter detected a problem with the earth (protective earth/PE) or with the neutral-to-earth connection. A sound earth is essential for electrical safety.
Likely causes:
- Loose or missing earth connection on the inverter or array
- Neutral and earth problem in the AC wiring or switchboard
- Fault in the building's main earth
What you can safely do:
- Do not touch the inverter, frames or cabling
- Leave the system off if it has shut down. Call a licensed electrician or us to test the earthing
45Master Fan1 ErrorWarning
What it means: A cooling fan isn't working properly, which can make the unit run hot and reduce output.
Likely causes:
- Fan blocked by debris
- Fan worn or failed
- Fan wiring fault
What you can safely do:
- From outside, check that nothing is blocking the vents
- Don't open the unit
- Call us to arrange a fan check or replacement
46Master Fan2 ErrorWarning
What it means: A cooling fan isn't working properly, which can make the unit run hot and reduce output.
Likely causes:
- Fan blocked by debris
- Fan worn or failed
- Fan wiring fault
What you can safely do:
- From outside, check that nothing is blocking the vents
- Don't open the unit
- Call us to arrange a fan check or replacement
47Master Fan3 ErrorWarning
What it means: A cooling fan isn't working properly, which can make the unit run hot and reduce output.
Likely causes:
- Fan blocked by debris
- Fan worn or failed
- Fan wiring fault
What you can safely do:
- From outside, check that nothing is blocking the vents
- Don't open the unit
- Call us to arrange a fan check or replacement
48Master Fan4 ErrorWarning
What it means: A cooling fan isn't working properly, which can make the unit run hot and reduce output.
Likely causes:
- Fan blocked by debris
- Fan worn or failed
- Fan wiring fault
What you can safely do:
- From outside, check that nothing is blocking the vents
- Don't open the unit
- Call us to arrange a fan check or replacement
49Lost Communication between Master and MeterWarning
What it means: The inverter isn't getting correct readings from its energy meter or current sensor (CT). This affects export limiting, battery charging and monitoring accuracy.
Likely causes:
- Meter or CT communication cable loose or damaged
- CT clamp fitted on the wrong cable or the wrong way round
- Meter has lost power or is faulty
What you can safely do:
- Check the app. Generation may still be running normally
- Don't open the switchboard
- Call us to check the meter/CT wiring. If your system has an export limit, this needs fixing promptly
50Lost Communication between M<->SFault
What it means: The equipment's self-checks found an internal problem (for example relays, measuring circuits, internal communication or power electronics). Some of these clear by themselves after a one-off event, but repeated alarms usually need a technician.
Likely causes:
- A one-off disturbance (for example a grid event)
- Internal component or circuit board fault
- Firmware issue
What you can safely do:
- Note the code, time and whether it clears by itself
- If your installer showed you the owner shutdown/restart procedure from the manufacturer's manual (summarised at the top of this page), you may restart the system once. Do not open covers or touch cabling.
- If the code returns or the system stays offline, call us. Internal faults are a warranty/technician job
51Lost Communication between inverter and Grid MeterWarning
What it means: The inverter isn't getting correct readings from its energy meter or current sensor (CT). This affects export limiting, battery charging and monitoring accuracy.
Likely causes:
- Meter or CT communication cable loose or damaged
- CT clamp fitted on the wrong cable or the wrong way round
- Meter has lost power or is faulty
What you can safely do:
- Check the app. Generation may still be running normally
- Don't open the switchboard
- Call us to check the meter/CT wiring. If your system has an export limit, this needs fixing promptly
52HMI EEPROM ErrorInfo
What it means: A monitoring or communication accessory (Wi-Fi/4G/data logger, display or clock) is reporting a problem. This usually doesn't stop the system generating.
Likely causes:
- Home Wi-Fi router changed, moved or restarted
- Weak Wi-Fi or mobile signal at the inverter
- Monitoring module or SIM/data issue
What you can safely do:
- Restart your home router and check it reaches the inverter location
- If you changed router or Wi-Fi password, the dongle needs reconfiguring (see the manufacturer's app guide or ask us)
- If generation looks normal but the alarm persists, call us
53HMI RTC ErrorInfo
What it means: A monitoring or communication accessory (Wi-Fi/4G/data logger, display or clock) is reporting a problem. This usually doesn't stop the system generating.
Likely causes:
- Home Wi-Fi router changed, moved or restarted
- Weak Wi-Fi or mobile signal at the inverter
- Monitoring module or SIM/data issue
What you can safely do:
- Restart your home router and check it reaches the inverter location
- If you changed router or Wi-Fi password, the dongle needs reconfiguring (see the manufacturer's app guide or ask us)
- If generation looks normal but the alarm persists, call us
54BMS Device ErrorFault
What it means: The battery management system has reported a problem with battery voltage, current, cells or internal hardware and has limited or stopped battery operation.
Likely causes:
- Cell voltage or capacity imbalance
- Over-charge or over-discharge conditions
- Internal battery hardware (relay, sensor, circuit board) fault
- Firmware or configuration mismatch between battery modules
What you can safely do:
- Do not open the battery or touch its terminals
- Note the exact alarm text and time from the app
- Call us. Battery faults should be handled by the installer or manufacturer
55BMS Lost.ConnFault
What it means: The inverter and battery (or parts inside the battery) have stopped talking to each other, so the battery may stop charging or discharging.
Likely causes:
- Battery switched off or in a protection state
- Loose or damaged communication cable
- Firmware or settings mismatch
What you can safely do:
- Check the battery's indicator lights and your monitoring app for other alarms
- Don't unplug or re-plug cables yourself
- Call us if it does not clear within a few hours
56CT Device ErrWarning
What it means: The inverter isn't getting correct readings from its energy meter or current sensor (CT). This affects export limiting, battery charging and monitoring accuracy.
Likely causes:
- Meter or CT communication cable loose or damaged
- CT clamp fitted on the wrong cable or the wrong way round
- Meter has lost power or is faulty
What you can safely do:
- Check the app. Generation may still be running normally
- Don't open the switchboard
- Call us to check the meter/CT wiring. If your system has an export limit, this needs fixing promptly
57AFCI Lost Com.ErrFault
What it means: The equipment's self-checks found an internal problem (for example relays, measuring circuits, internal communication or power electronics). Some of these clear by themselves after a one-off event, but repeated alarms usually need a technician.
Likely causes:
- A one-off disturbance (for example a grid event)
- Internal component or circuit board fault
- Firmware issue
What you can safely do:
- Note the code, time and whether it clears by itself
- If your installer showed you the owner shutdown/restart procedure from the manufacturer's manual (summarised at the top of this page), you may restart the system once. Do not open covers or touch cabling.
- If the code returns or the system stays offline, call us. Internal faults are a warranty/technician job
59Lost communication between inverter and PV MeterWarning
What it means: The inverter isn't getting correct readings from its energy meter or current sensor (CT). This affects export limiting, battery charging and monitoring accuracy.
Likely causes:
- Meter or CT communication cable loose or damaged
- CT clamp fitted on the wrong cable or the wrong way round
- Meter has lost power or is faulty
What you can safely do:
- Check the app. Generation may still be running normally
- Don't open the switchboard
- Call us to check the meter/CT wiring. If your system has an export limit, this needs fixing promptly
61Slave Phase1 Voltage HighWarning
What it means: The mains voltage the inverter measured was outside the limits allowed for your network, so it disconnected or reduced output to protect the grid. This is usually a grid condition, not a faulty inverter. ("Slave" refers to the inverter's secondary/redundant monitoring processor.)
Likely causes:
- High street voltage, common on sunny afternoons when many homes export solar
- Grid disturbances or voltage dips
- Long or undersized AC cabling between the inverter and the switchboard (installation issue)
- Grid protection settings that don't match your network's requirements
What you can safely do:
- Wait. The inverter reconnects by itself once voltage is back within limits
- Note the time of day it happens. If it happens most sunny days, tell us, because it may need a voltage check or a report to your network operator
- Don't try to change grid protection settings yourself. In Australia they are set to AS/NZS 4777.2 and your network operator's requirements
62Slave Phase1 Voltage LowWarning
What it means: The mains voltage the inverter measured was outside the limits allowed for your network, so it disconnected or reduced output to protect the grid. This is usually a grid condition, not a faulty inverter. ("Slave" refers to the inverter's secondary/redundant monitoring processor.)
Likely causes:
- High street voltage, common on sunny afternoons when many homes export solar
- Grid disturbances or voltage dips
- Long or undersized AC cabling between the inverter and the switchboard (installation issue)
- Grid protection settings that don't match your network's requirements
What you can safely do:
- Wait. The inverter reconnects by itself once voltage is back within limits
- Note the time of day it happens. If it happens most sunny days, tell us, because it may need a voltage check or a report to your network operator
- Don't try to change grid protection settings yourself. In Australia they are set to AS/NZS 4777.2 and your network operator's requirements
63Slave Phase2 Voltage HighWarning
What it means: The mains voltage the inverter measured was outside the limits allowed for your network, so it disconnected or reduced output to protect the grid. This is usually a grid condition, not a faulty inverter. (Phase 2/3 codes apply to three-phase models.) ("Slave" refers to the inverter's secondary/redundant monitoring processor.)
Likely causes:
- High street voltage, common on sunny afternoons when many homes export solar
- Grid disturbances or voltage dips
- Long or undersized AC cabling between the inverter and the switchboard (installation issue)
- Grid protection settings that don't match your network's requirements
What you can safely do:
- Wait. The inverter reconnects by itself once voltage is back within limits
- Note the time of day it happens. If it happens most sunny days, tell us, because it may need a voltage check or a report to your network operator
- Don't try to change grid protection settings yourself. In Australia they are set to AS/NZS 4777.2 and your network operator's requirements
64Slave Phase2 Voltage LowWarning
What it means: The mains voltage the inverter measured was outside the limits allowed for your network, so it disconnected or reduced output to protect the grid. This is usually a grid condition, not a faulty inverter. (Phase 2/3 codes apply to three-phase models.) ("Slave" refers to the inverter's secondary/redundant monitoring processor.)
Likely causes:
- High street voltage, common on sunny afternoons when many homes export solar
- Grid disturbances or voltage dips
- Long or undersized AC cabling between the inverter and the switchboard (installation issue)
- Grid protection settings that don't match your network's requirements
What you can safely do:
- Wait. The inverter reconnects by itself once voltage is back within limits
- Note the time of day it happens. If it happens most sunny days, tell us, because it may need a voltage check or a report to your network operator
- Don't try to change grid protection settings yourself. In Australia they are set to AS/NZS 4777.2 and your network operator's requirements
65Slave Phase3 Voltage HighWarning
What it means: The mains voltage the inverter measured was outside the limits allowed for your network, so it disconnected or reduced output to protect the grid. This is usually a grid condition, not a faulty inverter. (Phase 2/3 codes apply to three-phase models.) ("Slave" refers to the inverter's secondary/redundant monitoring processor.)
Likely causes:
- High street voltage, common on sunny afternoons when many homes export solar
- Grid disturbances or voltage dips
- Long or undersized AC cabling between the inverter and the switchboard (installation issue)
- Grid protection settings that don't match your network's requirements
What you can safely do:
- Wait. The inverter reconnects by itself once voltage is back within limits
- Note the time of day it happens. If it happens most sunny days, tell us, because it may need a voltage check or a report to your network operator
- Don't try to change grid protection settings yourself. In Australia they are set to AS/NZS 4777.2 and your network operator's requirements
66Slave Phase3 Voltage LowWarning
What it means: The mains voltage the inverter measured was outside the limits allowed for your network, so it disconnected or reduced output to protect the grid. This is usually a grid condition, not a faulty inverter. (Phase 2/3 codes apply to three-phase models.) ("Slave" refers to the inverter's secondary/redundant monitoring processor.)
Likely causes:
- High street voltage, common on sunny afternoons when many homes export solar
- Grid disturbances or voltage dips
- Long or undersized AC cabling between the inverter and the switchboard (installation issue)
- Grid protection settings that don't match your network's requirements
What you can safely do:
- Wait. The inverter reconnects by itself once voltage is back within limits
- Note the time of day it happens. If it happens most sunny days, tell us, because it may need a voltage check or a report to your network operator
- Don't try to change grid protection settings yourself. In Australia they are set to AS/NZS 4777.2 and your network operator's requirements
67Slave Frequency HighWarning
What it means: Grid frequency moved outside the allowed range, so the inverter disconnected or reduced output as the standards require. ("Slave" refers to the inverter's secondary/redundant monitoring processor.)
Likely causes:
- Short grid disturbance
- Running on a generator or a weak supply
- Grid settings that don't match the local network
What you can safely do:
- Wait for automatic reconnection
- If it happens often, record the times and contact us
68Slave Frequency LowWarning
What it means: Grid frequency moved outside the allowed range, so the inverter disconnected or reduced output as the standards require. ("Slave" refers to the inverter's secondary/redundant monitoring processor.)
Likely causes:
- Short grid disturbance
- Running on a generator or a weak supply
- Grid settings that don't match the local network
What you can safely do:
- Wait for automatic reconnection
- If it happens often, record the times and contact us
73Slave No Grid ErrorWarning
What it means: The inverter cannot see a normal mains supply, so it has stopped exporting to the grid (and a hybrid system may switch to backup). ("Slave" refers to the inverter's secondary/redundant monitoring processor.)
Likely causes:
- Power outage in your street or area
- A tripped or switched-off solar/inverter circuit breaker in the switchboard
- Loose AC connection between the switchboard and the inverter
What you can safely do:
- Check whether the rest of the house (or your neighbours) has power, and check your network operator's outage map
- Check the switchboard for a tripped solar supply main switch or inverter breaker. Only reset it once. If it trips again, leave it off and call an electrician
- Wait. Once normal grid power is back, the inverter normally reconnects by itself after its safety checks (often a few minutes)
- If grid power is normal but the alarm stays, call us
74Slave PV Input Mode ErrorFault
What it means: There is a firmware, model or configuration mismatch between parts of the system, so it can't run normally. ("Slave" refers to the inverter's secondary/redundant monitoring processor.)
Likely causes:
- Interrupted or partial firmware update
- Parts replaced with different firmware versions
- Incorrect model or country/region setting
What you can safely do:
- Don't try to reflash firmware yourself unless the manufacturer's app tells you to and it's an owner function
- Call us. We can arrange a firmware update or reconfiguration with the manufacturer
75Slave HW PV Curr HighFault
What it means: The equipment's self-checks found an internal problem (for example relays, measuring circuits, internal communication or power electronics). Some of these clear by themselves after a one-off event, but repeated alarms usually need a technician. ("Slave" refers to the inverter's secondary/redundant monitoring processor.)
Likely causes:
- A one-off disturbance (for example a grid event)
- Internal component or circuit board fault
- Firmware issue
What you can safely do:
- Note the code, time and whether it clears by itself
- If your installer showed you the owner shutdown/restart procedure from the manufacturer's manual (summarised at the top of this page), you may restart the system once. Do not open covers or touch cabling.
- If the code returns or the system stays offline, call us. Internal faults are a warranty/technician job
76Slave PV Voltage High ErrorFault
What it means: The DC voltage coming from the solar panels is higher than the inverter is rated for. Over-voltage can damage the inverter. ("Slave" refers to the inverter's secondary/redundant monitoring processor.)
Likely causes:
- Too many panels wired in series in a string (system design/installation issue)
- Very cold, bright mornings raise panel voltage
- Incorrect panel or string configuration after a change to the system
What you can safely do:
- Do not touch the DC isolator or cables unless the manufacturer's owner shutdown tells you to
- Call us. The string design needs to be checked by a licensed installer
77Slave HW Bus Volt HighFault
What it means: The equipment's self-checks found an internal problem (for example relays, measuring circuits, internal communication or power electronics). Some of these clear by themselves after a one-off event, but repeated alarms usually need a technician. ("Slave" refers to the inverter's secondary/redundant monitoring processor.)
Likely causes:
- A one-off disturbance (for example a grid event)
- Internal component or circuit board fault
- Firmware issue
What you can safely do:
- Note the code, time and whether it clears by itself
- If your installer showed you the owner shutdown/restart procedure from the manufacturer's manual (summarised at the top of this page), you may restart the system once. Do not open covers or touch cabling.
- If the code returns or the system stays offline, call us. Internal faults are a warranty/technician job
81Lost Communication D<->CFault
What it means: The equipment's self-checks found an internal problem (for example relays, measuring circuits, internal communication or power electronics). Some of these clear by themselves after a one-off event, but repeated alarms usually need a technician.
Likely causes:
- A one-off disturbance (for example a grid event)
- Internal component or circuit board fault
- Firmware issue
What you can safely do:
- Note the code, time and whether it clears by itself
- If your installer showed you the owner shutdown/restart procedure from the manufacturer's manual (summarised at the top of this page), you may restart the system once. Do not open covers or touch cabling.
- If the code returns or the system stays offline, call us. Internal faults are a warranty/technician job
83Master Arc Device ErrorFault
What it means: The equipment's self-checks found an internal problem (for example relays, measuring circuits, internal communication or power electronics). Some of these clear by themselves after a one-off event, but repeated alarms usually need a technician.
Likely causes:
- A one-off disturbance (for example a grid event)
- Internal component or circuit board fault
- Firmware issue
What you can safely do:
- Note the code, time and whether it clears by itself
- If your installer showed you the owner shutdown/restart procedure from the manufacturer's manual (summarised at the top of this page), you may restart the system once. Do not open covers or touch cabling.
- If the code returns or the system stays offline, call us. Internal faults are a warranty/technician job
84Master PV Mode ErrorFault
What it means: There is a firmware, model or configuration mismatch between parts of the system, so it can't run normally.
Likely causes:
- Interrupted or partial firmware update
- Parts replaced with different firmware versions
- Incorrect model or country/region setting
What you can safely do:
- Don't try to reflash firmware yourself unless the manufacturer's app tells you to and it's an owner function
- Call us. We can arrange a firmware update or reconfiguration with the manufacturer
85Authority expiresFault
What it means: The inverter reports that an authorisation/licence period has expired. SAJ gives no further detail. This code appears in the three-phase H2-T2 AU manual, not in the single-phase S2 list.
Likely causes:
- Not specified by the manufacturer
What you can safely do:
- Call us. We will check with SAJ
86DRM0 ErrorInfo
What it means: The DRM0 (demand response mode 0) input has been activated or its wiring/link is open. DRM0 tells the inverter to disconnect from the grid.
Likely causes:
- Your network or a demand-response device has issued a disconnect command
- The DRM link or DRED wiring is missing or faulty (if no device is fitted)
What you can safely do:
- Check with us whether a demand-response device is fitted at your site
- Call us. The DRM connection is installer wiring
87Master Arc ErrorSafety-critical
What it means: The inverter's arc-fault detection has picked up a pattern that looks like electrical arcing on the DC (solar) side, which can be a fire risk. The inverter shuts down DC power flow as a precaution.
Likely causes:
- Loose or poorly crimped DC connector
- Damaged DC cable
- Water or corrosion in a DC connector or isolator
What you can safely do:
- Do not reset it repeatedly and do not touch DC cables or isolators
- If you see smoke or flames or smell burning, keep clear and call 000
- Call us or a licensed electrician to inspect the DC wiring before the system is restarted
88Master SW PV Current HighFault
What it means: The equipment's self-checks found an internal problem (for example relays, measuring circuits, internal communication or power electronics). Some of these clear by themselves after a one-off event, but repeated alarms usually need a technician.
Likely causes:
- A one-off disturbance (for example a grid event)
- Internal component or circuit board fault
- Firmware issue
What you can safely do:
- Note the code, time and whether it clears by itself
- If your installer showed you the owner shutdown/restart procedure from the manufacturer's manual (summarised at the top of this page), you may restart the system once. Do not open covers or touch cabling.
- If the code returns or the system stays offline, call us. Internal faults are a warranty/technician job
89Battery Voltage HighFault
What it means: The battery management system has reported a problem with battery voltage, current, cells or internal hardware and has limited or stopped battery operation.
Likely causes:
- Cell voltage or capacity imbalance
- Over-charge or over-discharge conditions
- Internal battery hardware (relay, sensor, circuit board) fault
- Firmware or configuration mismatch between battery modules
What you can safely do:
- Do not open the battery or touch its terminals
- Note the exact alarm text and time from the app
- Call us. Battery faults should be handled by the installer or manufacturer
90Battery Current HighFault
What it means: The battery management system has reported a problem with battery voltage, current, cells or internal hardware and has limited or stopped battery operation.
Likely causes:
- Cell voltage or capacity imbalance
- Over-charge or over-discharge conditions
- Internal battery hardware (relay, sensor, circuit board) fault
- Firmware or configuration mismatch between battery modules
What you can safely do:
- Do not open the battery or touch its terminals
- Note the exact alarm text and time from the app
- Call us. Battery faults should be handled by the installer or manufacturer
91Battery Charge Voltage HighFault
What it means: The battery management system has reported a problem with battery voltage, current, cells or internal hardware and has limited or stopped battery operation.
Likely causes:
- Cell voltage or capacity imbalance
- Over-charge or over-discharge conditions
- Internal battery hardware (relay, sensor, circuit board) fault
- Firmware or configuration mismatch between battery modules
What you can safely do:
- Do not open the battery or touch its terminals
- Note the exact alarm text and time from the app
- Call us. Battery faults should be handled by the installer or manufacturer
92Battery OverLoadWarning
What it means: The backup/EPS (off-grid) output is overloaded or abnormal, so the system has limited or switched off backup power.
Likely causes:
- Too many or too large appliances on backup circuits during an outage (for example ovens, air conditioners, pumps)
- High start-up surge from motors or compressors
- A short circuit on a backup circuit
What you can safely do:
- Switch off large appliances on backup circuits
- Wait for the system to retry (some models lock out for a period after repeated overloads)
- If it trips with only small loads on, or you suspect a short circuit, call an electrician
93Battery SoftConnet TimeOutFault
What it means: The battery management system has reported a problem with battery voltage, current, cells or internal hardware and has limited or stopped battery operation.
Likely causes:
- Cell voltage or capacity imbalance
- Over-charge or over-discharge conditions
- Internal battery hardware (relay, sensor, circuit board) fault
- Firmware or configuration mismatch between battery modules
What you can safely do:
- Do not open the battery or touch its terminals
- Note the exact alarm text and time from the app
- Call us. Battery faults should be handled by the installer or manufacturer
94Output OverLoadWarning
What it means: The backup/EPS (off-grid) output is overloaded or abnormal, so the system has limited or switched off backup power.
Likely causes:
- Too many or too large appliances on backup circuits during an outage (for example ovens, air conditioners, pumps)
- High start-up surge from motors or compressors
- A short circuit on a backup circuit
What you can safely do:
- Switch off large appliances on backup circuits
- Wait for the system to retry (some models lock out for a period after repeated overloads)
- If it trips with only small loads on, or you suspect a short circuit, call an electrician
95Battery Open Circuit ErrorFault
What it means: The inverter and battery (or parts inside the battery) have stopped talking to each other, so the battery may stop charging or discharging.
Likely causes:
- Battery switched off or in a protection state
- Loose or damaged communication cable
- Firmware or settings mismatch
What you can safely do:
- Check the battery's indicator lights and your monitoring app for other alarms
- Don't unplug or re-plug cables yourself
- Call us if it does not clear within a few hours
96Battery Discharge Voltage LowInfo
What it means: The battery's state of charge or voltage is low, so the system has stopped discharging it to protect the cells.
Likely causes:
- Battery has been used down to its reserve level
- Several cloudy days with little solar to recharge
- Charging is disabled by the settings or by another fault
What you can safely do:
- Allow it to recharge from solar (or the grid, if your settings allow)
- Check the app for other alarms that could be stopping charging
- If it stays low for days in good sun, call us. Batteries left flat for long periods can be damaged
Manufacturer support contacts
| Contact | Phone | Email / channel |
|---|---|---|
| SAJ Australia technical support (website) | 1800 888 725 (+61 3 8353 1112) | support@saj-electric.com.au |
If Total Solar installed your system, contact us first.
Need help with a fault code?
Book a service call with our licensed electricians, or call us to talk it through. Have your fault code and a photo of the screen or app ready.