Hahn & Sohn C28NG petrol generator

C28NG is a natural gas generator for locations where natural gas is available and three-phase 400 V / 50 Hz power is required. The Cummins 4BT3.9-G36 engine has 4 cylinders and a displacement of 3.9 l, and is turbocharged with charge air cooling. Rated speed is 1,500 rpm and engine speed is controlled by the engine control unit (ECU).

• The electrical section consists of a single-bearing Stamford S0L2-M1/20KW alternator with brushless self-excitation, IP 23 protection, class H insulation, and voltage regulation accuracy of ±0.5%. The alternator has 12 leads.
• Control is provided by the ComAp InteliLite 4 AMF25 with a 7-digit display, integrated speed governor and AVR. The controller monitors generator output (kW, kVA), protects against overload, and monitors start failure. The enclosure is fitted with an emergency stop button.
• Directly on the machine are four industrial sockets mounted on a common rail: one blue and three red, labelled L1-L4. The switchboard contains a main CHINT 40 A four-pole circuit breaker with leakage current protection and a set of circuit breakers for the individual outputs. The enclosure is secured with locks, and the engine compartment is accessible from both sides.
• The gas section of the engine compartment contains a solenoid valve, gas pressure regulator, pressure gauge, and gas detector with a digital display. The exhaust is fitted with insulation. The base frame has forklift pockets and lifting eyes for crane handling.
• Gas consumption at continuous output: 10 m³/h at 100%, 8 m³/h at 75%, 5 m³/h at 50%, and 3 m³/h at 25% load.

Why customers choose it

• Natural gas operation - runs on natural gas from a fixed supply, with no need to refill diesel or petrol.
• Cummins engine and Stamford alternator - branded components listed directly on the enclosure.
• Three-phase 400 V output - suitable for workshops, construction sites, commercial premises, and backup power.
• Quiet enclosure - 72 dB at 7 m.
• ComAp AMF25 controller with display, protection functions, and emergency shutdown.
• Industrial sockets directly on the machine and circuit breakers in a lockable switchboard.
• 12-month or 1,000 operating-hour warranty on both the engine and alternator (whichever occurs first).

Practical tip

When planning the installation, allow for a weight of 1,016 kg and dimensions of 2,288 x 950 x 1,400 mm. The base frame has forklift pockets and lifting eyes. Connection to the gas supply and exhaust system should be carried out by an authorised specialist company.

Key features

• Output 25 kVA / 20 kW (prime), 28 kVA / 22 kW (standby)
• Fuel: natural gas
• Voltage 400 V, 50 Hz, three-phase, rated current 36 A
• Cummins 4BT3.9-G36 engine, 4 cylinders, 3.9 l, turbocharged with charge air cooling
• Stamford S0L2-M1/20KW alternator, IP 23, class H insulation, AVR ±0.5%
• ComAp InteliLite 4 AMF25 controller, 7-digit display
• Noise level 72 dB at 7 m
• 40 A main circuit breaker, sockets on the machine, emergency stop button
• Gas detector, pressure regulator, and solenoid valve in the engine compartment
• Warranty 12 months / 1,000 hours

Use / Installation / Operation

• Designed for operation with a natural gas supply.
• The machine is supplied as one complete unit on a frame designed for forklift and crane handling.
• Installation of the gas supply, exhaust system, and connection to the electrical mains must be carried out by an authorised specialist company.
• The installation, operating, and maintenance manual (safety instructions including risks associated with natural gas generators, installation, handling, commissioning, battery maintenance) is available for download from the product page.
• Fluid capacities: engine oil 16.4 l, coolant (engine only) 10 l.