Read the Nameplate Before You Buy
Wire a 380 V, 50 Hz compressor into a lower-voltage service and the contactor can fail on first start—before production begins. An air compressor nameplate is the fastest way to catch that mistake, but only if you read the right four fields: 流动, 压力, 电压, and duty. Get any one wrong and you either starve your tools or overpay for power. This guide explains each value so you can size the machine correctly and avoid a costly mismatch.
流动: Read Free Air Delivery, Not Motor Size
Free air delivery (FAD) is the real output of the machine—the volume of air delivered at inlet conditions, usually shown in m³/min or CFM. Compare two Panrui units: 一个 7.5 kW PR 7.5-8 delivers 1.1 立方米/分钟, 而一个 37 kW PR 37-8 delivers 9.6 立方米/分钟 0.8 兆帕. Motor power alone does not tell you usable air, because efficiency differs between designs. Also check whether the flow is stated as free air delivery or normalized volume; the difference changes how you size tools, 管道, and the air receiver.
压力: Bar vs. MPa and Why More Is Not Better
Working pressure is often printed as MPa or bar. On the nameplate, 0.8 MPa equals 8 酒吧和 0.7 MPa equals 7 酒吧. 规则很简单: set the pressure no higher than the highest-pressure tool plus piping loss. If a line loses 0.2 MPa between the machine and the point of use, 一个 0.8 MPa unit delivers only 0.6 MPa at the tool. Every extra bar raises specific power for the same flow, so an oversized pressure setting quietly increases the monthly electricity bill without producing more useful air.
Voltage, Phase, and Frequency
Industrial Panrui screw compressors are commonly rated 380 V / 50 Hz three-phase, while small dryers and accessories may be 220 V / 50 赫兹. Confirm all three values—voltage, phase, and frequency—before connection. A three-phase machine on single-phase service will not start correctly, 和一个 50 Hz motor on a 60 Hz supply can run faster and overheat. The nameplate is the final word for breaker sizing, cabling, and the transformer requirement, and it may also show the motor protection class, such as IP23 or IP55.
Duty Cycle: Know How Long the Machine Can Run
Screw compressors are typically rated for continuous duty, but verify the duty or load factor on the nameplate and controller. Duty cycle tells you how long a machine can run without overheating: S1 means continuous operation at rated load, while S3 means intermittent operation with a specified on/off cycle. Continuous duty supports a near-constant air draw; an intermittent-duty machine needs recovery time and can trip if pushed. Panrui variable-speed units use VFD starting to reduce inrush current and match output to fluctuating demand, which helps when your plant load is not constant.
Cross-Check the Nameplate Against the Whole System
A correct nameplate only pays off when the installation matches it. Panrui units are factory tested for 12 hours and designed for 52℃ ambient operation, with motor protection up to IP55 on some models. Check the supply voltage, pipe diameter, 接收器体积, and ambient temperature against those ratings. For help matching a unit to your demand, start with the main 螺杆空气压缩机 range and the variable-speed models.
Common Questions
- Which matters more, kW or m³/min? Use m³/min (FAD)—it is the actual air you can put to work.
- Can a 380 V unit run on 220 V? 不. Connect it to the nameplate voltage or provide the correct transformer and cabling.
- What does MPa mean? Megapascals. Roughly 0.1 MPa equals 1 酒吧, so 0.8 MPa is 8 酒吧.
- How do I convert m³/min to CFM? Multiply by about 35.31; for a rough estimate, 1 m³/min is close to 35 CFM.
Reading the air compressor nameplate is a five-minute check that prevents weeks of downtime and hidden energy cost. Match flow, 压力, 电压, and duty to your real demand, 然后 联系磐瑞 for a specification review before you commit.
