Primax sells hybrid inverters (solar, battery and grid together) and off-grid inverters (solar and battery, with the grid used only to charge or as a backup input). The same alarm can mean slightly different things on each type, so we note the difference where it matters. For the range itself, see our Primax inverter page.
What Primax inverter error codes actually mean
Every few milliseconds the inverter measures its inputs and outputs. When a reading leaves the safe window, it raises a code. Most Primax inverter problems fall into one of two kinds:
- Warnings (often shown with a beep or a flashing icon): the inverter keeps running, but something is near its limit, such as battery level or load.
- Faults: the inverter stops the affected function, such as charging, backup output or grid feeding, and may need the condition to clear and a restart.
A code is a symptom, not a diagnosis. The same "battery low" alarm can come from a genuinely empty battery, a wrong battery-type setting, or a loose battery cable. That is why the pattern (when, how often, under what load) matters as much as the number. Our general solar inverter faults guide covers how faults work on every brand.
Hybrid vs off-grid: one difference to know
On a hybrid Primax, "grid" or "utility" alarms affect both charging from the grid and, on export-capable models, feeding power back. On an off-grid Primax, the grid input is only a backup charger and bypass, so a utility alarm usually just means the inverter has moved to battery.
Primax alarm types
Battery
Voltage alarms
Load
Overload
Solar
PV input faults
Primax inverter fault codes by type: quick-check table
| Symptom on screen | Likely cause | Safe owner check | Call an engineer if... |
|---|---|---|---|
| Utility or grid fault, AC input abnormal | Load-shedding, tripped input breaker, or grid voltage or frequency out of range | Is the area supply off? Has the input breaker or voltage protector tripped? | It stays after supply returns, or shows while the grid is normal |
| Running on battery in daytime with grid present | Output mode setting (for example SBU), or grid out of range | Check the mode shown on screen; see SBU and SUB modes | You did not change the setting and it started on its own |
| PV input high, PV over voltage | Panel string voltage above the inverter's limit, often on cold, clear mornings | Note the time and PV voltage shown | Always; see PV over voltage |
| No PV input, PV low | Isolator off, night, heavy cloud, or a string fault | Is the solar isolator on? Is it daytime with sun? | It shows zero on a clear day |
| Battery low, battery under voltage | Battery at cut-off, high night load, or wrong battery-type setting | Check battery level and what was running | It appears soon after a full charge; see low battery voltage alarm |
| Battery not connected, BMS or communication error | Battery breaker off, loose cable, or lithium communication not set | Is the battery breaker and battery switch on? | It does not clear; see battery and inverter communication |
| Overload, output overload | Backup load above the rating, often motor or AC start | Switch off heavy loads | It overloads with normal loads; see inverter overload and beeping |
| Over temperature, fan fault | Heat, blocked vents, dust or a failing fan | Is it in sun or a closed room? Vents clear? | It continues after airflow improves; see inverter overheating |
| Earth or insulation fault (where shown) | DC leakage to earth, often after rain | Did it start after rain or washing? | It does not clear once dry; see isolation faults |
| Bus, inverter or internal fault | A fault inside the unit | Photograph it; do not keep restarting | Always |
The exact wording on your Primax screen may differ.
Primax inverter problems you can check safely
Owners should only look, read and record. Do not open the inverter or the battery, and do not touch DC cables or connectors.
- Photograph the display. Get the code, any icon (battery, sun, plug, fan, overload) and the beep pattern if you can record it. Note the date and time.
- Write down the model and serial number from the side label. The manual for that model is the only reliable code list.
- Check the grid. If the area has no supply, a utility alarm is expected; see inverter grid fault during load-shedding.
- Check breakers by eye. Note which breaker, isolator or voltage protector is off. A tripped breaker is a clue, not something to keep resetting.
- Reduce the load. For overload or heat, switch off the AC, water motor, iron or kettle and wait for the inverter to recover.
- Check the app if you have one. If your model has Wi-Fi monitoring, the alarm history shows when faults began. If the app shows offline but the screen is normal, it is a connection issue; see solar app offline.
- Restart once, in the manufacturer's order. Follow the shutdown and start-up sequence in the Primax manual, with its waiting time. Our guide on how to restart a solar system safely explains why order matters.
- Stop if it comes back. If the same code returns after one restart, leave the system off (if safe) and call an engineer with your photos.
Safety box. Burning smell, smoke, crackling, water near the inverter or battery, a swollen battery, or a shock from any metal part are emergencies, not error codes. Do not touch the equipment. If it is safe, switch off in the order in your manual (loads and grid input, then the solar isolator, then the battery breaker), keep people away and call a qualified engineer. Solar panels make DC voltage in any daylight, so the panel cables stay live even with everything else switched off. Never use water on an electrical fire.
What an engineer will check
- Settings first. Battery type (lithium or lead-acid), charge voltages, cut-off voltage, maximum charge current and output mode. A lithium battery set as lead-acid, or the reverse, causes repeated battery alarms. Our LiFePO4 vs tubular battery guide explains why the two need different settings.
- Battery health and cables. Voltage under load, terminal tightness, cable size and the BMS log on lithium batteries.
- Solar input. String voltage against the inverter's limit, polarity, connector condition and insulation.
- Grid input. Voltage and frequency at the terminals, especially in areas with very low or very high supply.
- Heat. Fan, heat sink dust, clearances and ventilation.
- Internal faults. Bus or hardware codes usually mean a manufacturer's warranty or repair case. Keep your invoice and serial number ready.
How to prevent repeat alarms
- Ask for the battery settings to be written down at commissioning, and do not change them without advice.
- Keep heavy loads (AC, motor, iron) off the backup output unless the system was sized for them.
- Mount the inverter in shade with free airflow, and clean dust from vents regularly.
- Have strings designed for the coldest winter morning, not only for summer.
- Watch for warnings in the app or on the screen; act before they become faults.
If you are choosing a new inverter, our best solar inverter in Pakistan guide compares brands by use case.
How Solar Works helps
For systems we install, our own engineers handle after-sales, and our 1-year service warranty applies under the applicable project terms. Manufacturer faults go through the manufacturer's warranty process. If your Primax shows an error code, WhatsApp 0336 666 4321 with a photo of the screen and the inverter model from the side label.
Frequently asked questions
Where do I find the Primax inverter error codes list?
In the user manual for your exact model. Primax code numbers are not the same on every model, so a list for a different inverter can mislead you. If you have lost the manual, ask the installer or seller for the one matching your side label.
Why does my Primax inverter show a utility or grid fault?
Usually because there is no grid supply, an input breaker or voltage protector has tripped, or the grid voltage is out of range. During load-shedding this is normal. If it stays after the supply returns, call an engineer.
Why does my Primax inverter keep showing battery low after charging?
Common reasons are a heavy night load, a battery-type or cut-off setting that does not match the battery, loose battery cables, or an ageing battery. Note when it appears and what was running, and ask an engineer to check the settings.
Why is my Primax inverter beeping?
Beeping is a warning sound. It often means overload, low battery or grid loss. Read the screen, switch off heavy loads, and see our inverter overload and beeping guide.
How to fix Primax inverter overload?
Switch off heavy loads such as ACs, motors and irons, let the inverter recover, and restart by the manual if needed. If it overloads with only normal loads, the inverter or wiring needs checking.
Can I reset Primax inverter fault codes myself?
Once, using the sequence in your manual. Do not keep resetting PV over voltage, earth fault, battery communication or internal fault codes; call an engineer.
Do you repair Primax inverters installed by other companies?
Share the model, a photo of the code and a short description on WhatsApp 0336 666 4321 first.
Help across Punjab
Send the alarm name and a photo of the screen on WhatsApp. We inspect systems in Faisalabad, Lahore and across Punjab, including systems installed by other companies, as a paid visit.
Send us
Photos of the inverter screen or app alarm, your inverter and battery model, and when the problem happens.