How to choose a suitable generator set?

I. First, distinguish the purpose of use: Primary/Standby, never choose the wrong power rating

1) Definition of Use (90% of people make this mistake)

– Primary Power Supply (24/7 continuous power generation, construction sites/remote areas without mains power)

PRP (Power Proportion) = Total Load×1.1, can run continuously indefinitely

– Backup Emergency (Hospitals/Factory/Property Management, only used during power outages)

Standby Power = Critical Load×1.2; only 1 hour of full load is allowed within 12 hours

⚠️ Never run the backup unit continuously for extended periods, as this will burn out the motor and significantly shorten its lifespan.

2) Power Calculation (Essential for Motor Loads)

– Resistive Loads (Lights, Heating): 1:1 calculation

– Inductive Loads (Water Pumps/Fans/Air Compressors): Starting current 3–7 times, must have a larger margin

– Unit Conversion: 1kVA ≈ 0.8kW, don’t be fooled by vendors using kVA to inflate power ratings.

– Simple rule of thumb: Total power consumption (kW) × 1.3 = Recommended generator set (kW)

3) Altitude/Temperature Correction

– For every 1000m increase in altitude, power decreases by 8%–12%, fuel consumption increases.

– For temperatures >40℃, reduce capacity and increase cooling.

II. Engine Selection (The Heart of the Machine–Determining Fuel Consumption and Lifespan)

Prioritize major domestic brands: High cost-performance ratio (for construction sites/factories)

– King of cost-performance, extremely cheap parts, fuel-efficient, 20–800kW range, first choice for civilian use.

– Heavy-duty and durable, suitable for long-term loads in mining/industrial applications, long lifespan.

– Quiet operation, preferred for hospitals, hotels, and residential areas.

If budget allows, consider imported brands (data centers/hospitals/uninterrupted critical loads).

III. Generator (Avoid aluminum core generators)

– Always choose a full copper brushless motor. Aluminum cores heat up quickly, are prone to burning out, have unstable voltage, and a high failure rate.

– Voltage regulation accuracy: ≤±0.5%, precision equipment (UPS/servers) ≤3% harmonics. Insulation Class H, AVR automatic voltage regulation, domestic standard 380V three-phase/50Hz

IV. Unit Type Selection (by Site)

– Open rack type: Inexpensive, good heat dissipation, high noise → Factory/Field

– Silent enclosure type: ≤65dB → Residential areas, hospitals, hotels, urban areas

– Mobile trailer: Temporary power supply for construction sites, mobile power supply in the field

– Fully automatic ATS cabinet: Automatic restart 10 seconds after mains power failure, essential for unattended operation

V. Control System Configuration

– Basic: Manual start/stop, voltage/water temperature/oil pressure protection

– Advanced: Automatic ATS switching, parallel grid connection, remote monitoring, mobile APP

– Use high-quality brands, quality guaranteed

VI. Cooling & Accessories

– <50kW: Air cooling, inexpensive and simple

≥50kW: Water cooling, stable, high temperature resistant, essential for long-term operation

– Standard configuration: Fuel base tank (≥8h range), muffler, battery, protection

– Optional Equipment: Low-temperature preheating, external large fuel tank, rainproof canopy, noise reduction system

VII. Warranty & After-sales Service (Crucial)

– Industry Standard: 1 year/1000 hours warranty for the whole machine, whichever comes first

– Major Brands: 2 years/2000 hours nationwide warranty

– Must have a local service center, 24-hour on-site service for faults, and readily available parts

VIII. Avoid These Pitfalls (Don’t Buy From These Brands)

1. Falsely Labeled Power: Using kVA to impersonate kW, labeling small machines as high power

2. Refurbished machines, assembled generic engines, no certificate of conformity

3. Aluminum-clad copper motors, inferior generic controllers

4. Failure to label common/standby power, confusing consumers

5. No ATS, no full overload/water temperature/oil pressure protection