Несоответствие частоты может привести к снижению номинальных характеристик импортного винтового компрессора примерно на 17% еще до того, как машина будет введена в эксплуатацию. You pay the invoice, clear customs, and wire the panel, only to find the motor runs hot or delivers less air than the production line demands. Specifying the right power supply and frequency for an imported compressor costs nothing at the quote stage and prevents the most expensive class of startup failures.
Specify power supply and frequency before you sign the order
Voltage and frequency are not afterthoughts for a screw compressor. They determine motor speed, airflow, current draw, охлаждение, and whether the control panel powers up correctly. If the purchase order only says “380V,” the supplier cannot know whether you mean 380V/50Hz, 400V/50Hz, or a 60Hz grid with a different phase balance.
- Nominal supply voltage. State the actual site voltage, such as 380V, 400В, 415В, or 460V, not a vague regional label.
- Частота. Confirm 50Hz or 60Hz; the motor and cooling fan behave differently under each.
- Phase configuration. Industrial screw compressors are almost always 3-phase. Record phase balance and voltage tolerance, commonly ±10%.
- Control circuit voltage. Ask whether the controller needs a separate 110V or 220V feed.
- Starting method. Check direct-on-line, star-delta, soft start, or variable-speed drive, because each changes inrush current and upstream breaker sizing.
The 50Hz vs 60Hz mistake that changes airflow and motor load
Frequency controls how fast a direct-coupled motor spins. A 60Hz motor run on a 50Hz supply turns about 16–17% slower, so it produces roughly 16–17% less free air delivery and the shaft fan also moves less cooling air. A 50Hz motor pushed onto 60Hz runs about 20% faster; airflow rises, but power demand climbs much faster, which can overload a motor that was not wound for that condition.
А винтовой компрессор с регулируемой скоростью gives you more flexibility, but the drive still has a rated input voltage and frequency range. Ask for the motor nameplate photo and a factory test report at your country’s frequency before shipment, not after delivery.
Field proof: the right protection prevents nuisance tripping
Imported machines are not the problem; unspecified electrical conditions are. Панруи, например, fits its flagship screw compressors with a D-type motor-duty circuit breaker instead of a C-type household breaker. That matters because compressor startup current can repeatedly trip the wrong breaker, shutting down a line that should have been running.
The same discipline applies to installation. A Shenzhen plastics manufacturer runs three 37kW Panrui two-stage screw compressors, a setup that works because the load, мотор, protection, and local 50Hz supply were confirmed before commissioning. That is the difference between a smooth start-up and a burned motor on day one.
Возражение: “The supplier says the motor is dual-rated”
Dual-rated does not mean every rating is available at the same output and temperature rise. A 50/60Hz motor may still need a different winding, service factor, or drive derating for your specific voltage. Ask for a nameplate that lists voltage, частота, full-load amps, and service factor, then confirm those values against the actual panel at your site.
Specification checklist for imported compressors
- Get the motor nameplate showing volts, hertz, amps, and service factor.
- Write the site voltage, tolerance, частота, and phase sequence into the PO.
- Confirm breaker type, cable sizing, and grounding before wiring.
- Request a factory test report at the buyer’s frequency.
- Keep the ротационный винтовой воздушный компрессор commissioning checklist tied to the same electrical data.
When the power supply and frequency are locked down early, the compressor arrives ready to run, not ready to rework. If you are specifying an imported screw compressor and want the motor, водить машину, breaker, and control circuit matched to your grid, связаться с Панруи with your site voltage and frequency before you approve the quote.
