Select a solar pump inverter by checking three systems together: the AC pump motor, the photovoltaic array and the required water delivery. Matching only the panel wattage to the motor kW can miss important voltage and hydraulic limits.
What does a solar pump inverter do?
A solar pump inverter converts DC electricity from photovoltaic modules into AC power for a compatible pump motor. MPPT adjusts operation to use the available solar power as conditions change. Water output therefore depends on sunlight and the hydraulic system as well as motor size.
INOMAX MAX500-PV is intended for AC pumping applications. A DC or BLDC pump with a dedicated controller is a different product category and must not be assumed compatible.
Start with water demand and the motor
Define the required daily water volume, flow rate, total dynamic head and source conditions. For a borehole, consider drawdown and pipe losses rather than using well depth alone. Review the pump curve and the operating speed range with the pump supplier.
Then obtain the motor voltage, phase count, rated current, power and starting requirements. The inverter’s output configuration must suit the actual motor; a three-phase output model should not be selected for a single-phase motor without explicit compatibility confirmation.
Check the PV array over its temperature range
| Check | Reason |
|---|---|
| Cold-weather string open-circuit voltage | It must remain within the selected inverter maximum DC input limit. |
| Hot-weather operating voltage | The array must support the required operating and MPPT voltage range. |
| Array current and input limits | Parallel strings must be assessed against the permitted input current and protection design. |
| Available solar power | Daily pumping depends on irradiation, temperature, shading and system losses. |
| Output voltage and boost requirement | A voltage-boost version is a specific configuration, not a feature to assume on every solar VFD. |
MPPT does not create extra solar energy
MPPT helps locate a useful operating point on the array’s power curve. It cannot compensate for an undersized array, severe shading or insufficient sunlight. Water storage may help meet demand outside peak sun hours; any battery or backup-power arrangement requires a separately defined system design.
Where INOMAX MAX500-PV fits
The MAX500-PV solar pump inverter is INOMAX’s dedicated MPPT AC pump drive offering. Specify the motor, PV input, any voltage-boost requirement and the installation environment so the correct version can be selected.
For outdoor or harsh locations, confirm the actual enclosure and installation provisions. Ask how dry-run detection, tank-level signals and backup supply are implemented in the supplied version. Do not assume all options or wiring arrangements are standard.
Information for an accurate quotation
Send the motor nameplate, pump curve, daily water requirement, head, location, PV module datasheet, proposed string arrangement, cable lengths and enclosure requirement. State whether an existing array or pump must be reused.
Frequently asked questions
How many solar panels do I need?
It depends on module ratings, string voltage, available sunlight, pump duty and the selected inverter. A fixed panel-to-motor multiplier cannot replace these checks.
Can I connect PV and mains directly together?
No. Use only the input arrangement, switching and protections approved for the exact inverter and system design. Input compatibility must be confirmed before wiring.