Haifeng Machinery

Cummins 4B3.9-G12 vs SDEC 4Z3.0-G12

The Cummins 4B3.9-G12 and SDEC 4Z3.0-G12 are both diesel generator engines in a similar power class. Both are rated at roughly 38 kVA. Displacement is 3.9 L versus 3 L. The table below compares their full specifications side by side.

SpecificationCummins 4B3.9-G12SDEC 4Z3.0-G12
Headline rating38 kVA38 kVA
Standby (50 Hz)30 kWe30 kWe
Prime (50 Hz)25 kWe27 kWe
Standby (60 Hz)35 kWe30 kWe
Prime (60 Hz)28 kWe27 kWe
Displacement3.9 L3 L
ConfigurationL4L4
Cylinders44
Rated speed1,500 / 1,800 RPM1,500 / 1,800 RPM
FuelDieselDiesel
CoolingLiquid-CooledLiquid-Cooled
EmissionsUnregulatedChina National Stage II / Unregulated
Dry weight
OriginChinaChina

Choosing between Cummins 4B3.9-G12 and SDEC 4Z3.0-G12

Use this comparison as an engineering shortlist, then confirm the complete generator package against load profile, voltage, 50/60 Hz frequency, duty class, emissions rules, cooling margin, altitude, ambient temperature, enclosure design, controller features, and alternator sizing.