Solinteg error codes explained

Grid power outage, AC switch or circuit is disconnected.

What you can do

• Check whether the rest of your house or street has power, and check your network operator's outage map
• Check the switchboard for a tripped solar/inverter breaker - reset it once only; if it trips again, leave it off and call an electrician
• Once normal power is back the inverter usually reconnects on its own within a few minutes
• If the power is normal but the alarm stays, call your installer

MHT-4~20K three-phase hybrid · Guide only. All work must be done by a licensed electrician. Get help with this code

Grid overvoltage or undervoltage: the grid voltage is higher or lower than the set protection value.

What you can do

• This is usually caused by the mains supply, not the solar system
• The inverter normally reconnects by itself once grid voltage is back in range
• If it happens often (especially on sunny afternoons), note the times and call your installer - they can check the voltage and settings and talk to the network if needed

MHT-4~20K three-phase hybrid · Guide only. All work must be done by a licensed electrician. Get help with this code

Grid over- or under-frequency: the grid frequency is higher or lower than the set protection value.

What you can do

• This is caused by the mains frequency moving outside the allowed range, usually briefly
• The inverter reconnects by itself once the grid is stable
• If it keeps happening, note the times and call your installer

MHT-4~20K three-phase hybrid · Guide only. All work must be done by a licensed electrician. Get help with this code

DC injection high - the inverter detects a higher DC component in the AC output.

What you can do

• Restart the system once using the owner shutdown/start-up steps in your manual
• If it comes back, call your installer

MHT-4~20K three-phase hybrid · Guide only. All work must be done by a licensed electrician. Get help with this code

Low system insulation resistance, generally caused by poor insulation to ground of the modules/cables or a rainy, damp environment.

What you can do

• Keep clear - do not touch the panels, rooftop isolators, DC cables or the inverter
• Note the code and whether it appears in wet weather or early morning - this helps the electrician
• If you see smoke, smell burning or hear crackling, keep everyone away and call 000
• Call a licensed electrician or Total Solar - insulation and earth faults need testing with proper equipment

MHT-4~20K three-phase hybrid · Guide only. All work must be done by a licensed electrician. Get help with this code

Excessive leakage current.

What you can do

• Keep clear and do not touch the inverter or cabling
• Note the code, date and time
• If you see smoke, smell burning or hear crackling, keep everyone away and call 000
• Call a licensed electrician or Total Solar - this alarm means current may be leaking to earth

MHT-4~20K three-phase hybrid · Guide only. All work must be done by a licensed electrician. Get help with this code

PV voltage is too high.

What you can do

• Do not touch the DC isolators or cables
• Note the time - this often shows on cold, very sunny mornings
• Call your installer - the panel strings may need to be checked against the inverter's limits

MHT-4~20K three-phase hybrid · Guide only. All work must be done by a licensed electrician. Get help with this code

Internal DC bus voltage is too high.

What you can do

• Do not touch the DC isolators or cables
• Note the time - this often shows on cold, very sunny mornings
• Call your installer - the panel strings may need to be checked against the inverter's limits

MHT-4~20K three-phase hybrid · Guide only. All work must be done by a licensed electrician. Get help with this code

The temperature inside the inverter is too high and out of the safe range.

What you can do

• Check from a safe distance that the inverter is shaded, has clear space around it and that nothing is blocking the vents
• It usually recovers once it cools down
• If it repeats often or you can hear a noisy/failed fan, call your installer

MHT-4~20K three-phase hybrid · Guide only. All work must be done by a licensed electrician. Get help with this code

Internal communication failure (e.g. caused by a strong external magnetic field).

What you can do

• Note the code, time and whether it clears by itself
• You may restart the system once using the owner shutdown/start-up steps in your manual. Do not open covers or touch cabling
• If the code returns or the system stays offline, call your installer - internal faults are a warranty/technician job

MHT-4~20K three-phase hybrid · Guide only. All work must be done by a licensed electrician. Get help with this code

Internal storage (memory) anomaly (e.g. caused by a strong external magnetic field).

What you can do

• Note the code, time and whether it clears by itself
• You may restart the system once using the owner shutdown/start-up steps in your manual. Do not open covers or touch cabling
• If the code returns or the system stays offline, call your installer - internal faults are a warranty/technician job

MHT-4~20K three-phase hybrid · Guide only. All work must be done by a licensed electrician. Get help with this code

GFCI (leakage-current sensor) device anomaly.

What you can do

• Note the code, time and whether it clears by itself
• You may restart the system once using the owner shutdown/start-up steps in your manual. Do not open covers or touch cabling
• If the code returns or the system stays offline, call your installer - internal faults are a warranty/technician job

MHT-4~20K three-phase hybrid · Guide only. All work must be done by a licensed electrician. Get help with this code

AC current sensor anomaly.

What you can do

• Note the code, time and whether it clears by itself
• You may restart the system once using the owner shutdown/start-up steps in your manual. Do not open covers or touch cabling
• If the code returns or the system stays offline, call your installer - internal faults are a warranty/technician job

MHT-4~20K three-phase hybrid · Guide only. All work must be done by a licensed electrician. Get help with this code

Relay self-check failed - neutral and earth cables not connected well on the AC side, or an occasional failure.

What you can do

• Note the code, then restart the system once using the owner shutdown/start-up steps in your manual
• If the code comes back, call your installer - this is an internal fault that needs a licensed electrician or the manufacturer

MHT-4~20K three-phase hybrid · Guide only. All work must be done by a licensed electrician. Get help with this code

Internal fan anomaly.

What you can do

• From outside, check that nothing is blocking the vents
• Don't open the unit
• Call your installer to arrange a fan check or replacement

MHT-4~20K three-phase hybrid · Guide only. All work must be done by a licensed electrician. Get help with this code

External fan anomaly.

What you can do

• From outside, check that nothing is blocking the vents
• Don't open the unit
• Call your installer to arrange a fan check or replacement

MHT-4~20K three-phase hybrid · Guide only. All work must be done by a licensed electrician. Get help with this code

Internal DC bus voltage is too high (hardware protection).

What you can do

• Note the code, time and whether it clears by itself
• You may restart the system once using the owner shutdown/start-up steps in your manual. Do not open covers or touch cabling
• If the code returns or the system stays offline, call your installer - internal faults are a warranty/technician job

MHT-4~20K three-phase hybrid · Guide only. All work must be done by a licensed electrician. Get help with this code

Solar power is low.

What you can do

• This is normal at dawn, dusk, in heavy cloud or when panels are shaded
• No action needed if it clears once the sun is up
• If it shows in full sun, call your installer

MHT-4~20K three-phase hybrid · Guide only. All work must be done by a licensed electrician. Get help with this code

Battery voltage is too high.

What you can do

• Note the code and the battery state of charge shown in the app
• Let the system run - some battery voltage protections clear by themselves after charging or discharging
• If the alarm stays or keeps returning, call your installer - don't open or disconnect the battery yourself

MHT-4~20K three-phase hybrid · Guide only. All work must be done by a licensed electrician. Get help with this code

Backup output voltage is too high.

What you can do

• Switch off large appliances on backup circuits
• Wait for the system to retry
• If it trips with only small loads on, or you suspect a short circuit, keep clear and call a licensed electrician

MHT-4~20K three-phase hybrid · Guide only. All work must be done by a licensed electrician. Get help with this code

Internal DC bus voltage is too low.

What you can do

• Note the code, time and whether it clears by itself
• You may restart the system once using the owner shutdown/start-up steps in your manual. Do not open covers or touch cabling
• If the code returns or the system stays offline, call your installer - internal faults are a warranty/technician job

MHT-4~20K three-phase hybrid · Guide only. All work must be done by a licensed electrician. Get help with this code

Other (hardware) faults.

What you can do

• Note the code, time and whether it clears by itself
• You may restart the system once using the owner shutdown/start-up steps in your manual. Do not open covers or touch cabling
• If the code returns or the system stays offline, call your installer - internal faults are a warranty/technician job

MHT-4~20K three-phase hybrid · Guide only. All work must be done by a licensed electrician. Get help with this code

Backup output overload.

What you can do

• Turn off some large appliances (air-conditioners, ovens, kettles, pool pumps) - backup outputs have a power limit
• The system usually recovers by itself once the load drops
• If it keeps happening with normal loads, call your installer

MHT-4~20K three-phase hybrid · Guide only. All work must be done by a licensed electrician. Get help with this code

Backup output overvoltage.

What you can do

• Switch off large appliances on backup circuits
• Wait for the system to retry
• If it trips with only small loads on, or you suspect a short circuit, keep clear and call a licensed electrician

MHT-4~20K three-phase hybrid · Guide only. All work must be done by a licensed electrician. Get help with this code

Backup output over-frequency.

What you can do

• Switch off large appliances on backup circuits
• Wait for the system to retry
• If it trips with only small loads on, or you suspect a short circuit, keep clear and call a licensed electrician

MHT-4~20K three-phase hybrid · Guide only. All work must be done by a licensed electrician. Get help with this code