A solar pump inverter needs three planned checks a year, not one annual visit: a check before the dry season when demand is highest, a check before the wet season when water, dust and corrosion do their damage, and a restart check after any idle period. At each checkpoint, work through the same five areas — seals and enclosure, wiring and earthing, heat and dust, fault history, and remote status where fitted — and write down what you find, so a change from one season to the next is visible before it becomes a trip. Only qualified electrical personnel should open terminals or work on live parts; other checks in this guide are visual inspections with the system isolated where the manual requires it.
The three checkpoints at a glance
| Checkpoint | Main focus | Why it matters |
|---|---|---|
| Before the dry season | Water level, array soiling, heat and dust | Demand peaks while water and cooling margins fall |
| Before the wet season | Seals, glands, drainage and corrosion | Rain finds every weak gland and standing water threatens the enclosure |
| Restart after an idle period | Parameters, fault history and water level | Settings, water and connections can change while the system is stopped |
Before the dry season
Check the borehole or tank level and recovery against the pumping duty, because a dry-run trip in the dry season is often a water-source change, not a drive fault. Clean the array and clear dust from heatsink fins and air paths, following the manual, so the drive does not derate in heat. Inspect gaskets and cable glands for cracking, dust tracks and loose fittings, and confirm shade and airflow clearance. On the QB100-PV Solar Pump Inverter White Plastic Shell 0.4–37kW page, MPPT efficiency is rated up to 99%, but that rating does not compensate for a soiled array or a blocked heatsink.
Before the wet season
Check that cable entries and glands face down where the manual requires it, that unused entries are sealed, and that the drive sits above local flood level and irrigation spray. Look for salt crust, corrosion on fixings and hinges, and water tracks at seals. For the difference between coastal and inland routines, see Coastal Salt Fog vs Dusty Inland: How Does Outdoor Protection Differ? and the mounting rules in IP65 Solar Pump Inverter: Outdoor Installation Without a Control Cabinet. IP65 means dust-tight and protected against water jets; it does not mean submersible, condensation-proof or corrosion-proof by default.
Restart after an idle period
Before the first run after idle, confirm the water level, check for obvious cable or junction-box damage, and confirm the drive motor parameters still match the pump nameplate. Record the fault history first and investigate any repeat trip instead of clearing it. The Solar Pump Inverter Fault Codes and Dry-Run Protection guide explains what low-voltage, overcurrent, dry-run, overvoltage and overheating indications usually mean, and why a repeat dry-run trip should never be silenced by disabling protection.
How to run a seasonal check, step by step
- Isolate for inspection where required. Isolate PV and any AC supply before opening covers or touching terminals, and follow the manual for safe access.
- Inspect seals and the enclosure. Check gaskets for cracks, swelling, salt crust or dust tracks, check cable glands for tightness and correct size, and seal unused entries.
- Inspect wiring and earthing visually. Look for damaged cables, wet junction boxes, loose connections and corrosion at fixings. Leave any terminal work to qualified personnel.
- Clear heat and dust paths. Clear heatsink fins and air paths, confirm shade and manual clearances, and check fans where fitted, following the manual.
- Review the fault history. Write down every fault indication, its time pattern and the conditions at the time, and compare it with the previous season before resetting anything.
- Check remote status where fitted. Confirm GPRS, 4G or Wi-Fi reporting, signal and alarm behaviour where a module is fitted. Remote communication is optional or model-dependent on the QB100-PV and IDEEI IP65 Solar Pumping VFD 0.4–37kW product pages, so confirm the module before treating an offline dashboard as a drive fault.
- Run a controlled test. Restore power, observe the display and MPPT behaviour, and watch flow, rotation and current on the first run. Use the wiring checklist in How Do I Wire a Solar Pump Inverter to Panels and a Pump? if anything was disturbed.
- Log the result. Record the date, water level, faults found, cleaning done and any part or setting that needs follow-up, and set the next checkpoint date.
Seasonal symptoms and the first check
| Symptom | Seasonal cause to check first | First action |
|---|---|---|
| Overheating or derating in hot weather | Dust-packed heatsink or lost shade | Clear fins and air paths and restore shade and clearance |
| Repeat dry-run trips | Falling water level or slower recovery | Check level, intake depth and duty; tune delay only as the manual allows |
| Trip after rain or washing | Water at a gland, junction box or seal | Isolate, dry and inspect seals and entries before restarting |
| Fault returns on restart after idle | Changed water, cable or parameter state | Record the code and pattern and diagnose before resetting again |
| Remote dashboard offline | Module, signal or antenna issue | Confirm the fitted module and signal before suspecting the drive |
Frequently asked questions
Do I need to shut down a solar pump inverter for the wet season?
No, and this is the trap. A correctly installed IP65 drive is made to stay outdoors in rain; shutting it down for the season only creates a restart problem later. What the wet season does require is a pre-season seal, gland and drainage check, and isolation only while you inspect or repair it. Never let the unit sit in standing water, because IP65 does not cover immersion.
How often should seals and glands be inspected?
At least once a year, and more often in salty, dusty or high-UV environments. In practice, that minimum is why the dry-season and wet-season checks both include seals: a gasket that was sound last year is not automatically sound this year.
Should I clear fault codes at the seasonal check?
Record them first, then clear only after the cause is found and fixed. A cleared code without a diagnosis hides the pattern that would have shown whether the fault is seasonal, a water problem or a wiring problem.
My remote dashboard is offline. Is the inverter faulty?
Not necessarily. Remote communication is optional or model-dependent, so first confirm which module is fitted, whether it has signal and whether its antenna and cable entries are intact. If the pump itself runs normally and only the remote link is down, the fault is in the monitoring path, not necessarily in the drive.
Low flow in the dry season: is it a maintenance problem?
Check water level and recovery, array soiling and heatsink airflow before changing drive settings. Low flow in the dry season is often a water or power problem, and raising a limit to force more flow can turn a water problem into a dry-run failure.