The Cummins CM850 is an engine control module designed to work specifically with Cummins generator-drive engines. Cummins has designed and manufactured diesel engines since 1919. G-drives are diesel-powered engines used to provide a prime, standby or continuous power source. G-drive engines are used by almost all sectors of business, including industrial, commercial, financial, construction and healthcare.

On Engine

The CM850 engine control module provides integrated on-engine fuel and feature controls. It has a simplified original equipment manufacturer’s interface with the capability for hard-wired and electronic multiplexing operation. It also has an integrated engine sensor suite and harness, and it is certified for operation with most genset controllers.


The CM850 also features engine control software that incorporates three G-drive control features. These include fixed speed operation at 50, 60 or 400 hertz; adjustable speed bias, frequency offset, droop and engine response gains, and idle/rated and alternate frequency controls. It has high-speed serial data communications, engine operational data and diagnostic messages. The CM850 is also OEM adaptable with service tool trims.

Engine Protection

The engine control software also has engine protection features that include overspeed, low-oil pressure and high-engine-temperature functions. It also includes a diagnostic and fault management system that provides fault reporting, duty cycle mapping, trend logs and fault snapshot logs. Engine torque and speed management with high-pressure common rail fuel injection and Cummins service support are also included.


Cummins offers more than 50 G-drive engine models, in both 50 hertz and 60 hertz, that range from 1.3 liters to 78 liters in size. The line includes the B-Series of small and light engines and Cummins’ most economical models. The QSB-Series feature greater engine manipulation capabilities with full-authority electronic controls. The KTA19 has a six-cylinder, in-line configuration that provides combustion efficiency and fuel economy. Cummins’ QSK19-Series is the company's first diesel engine that is 650-kilovolt-amps capable in six cylinders. The Cummins QSK23-Series was designed to meet present and future worldwide emissions regulations, but also provide high fuel economy and high power density.


The Cummins QSK78 is the company’s most powerful engine in its class. It is a 78-liter, 18-cylinder engine. The QSK78 also has base engine components that produce a high power density. The QSK78 has service options that can provide extended oil and filter change intervals. It provides 3,000 kilovolt amps of standby power and 2,740 kilovolts of prime power output.