Lots of small and medium-sized equipment builders today have the Tier 4 Diesel Blues. Building a new machine with a diesel engine used to be simple. You mounted the engine, supplied a fuel system, supplied a cooling system (unless it was an air-cooled diesel!), and electricity to turn the starter motor. Voilà! Your machine was ready to run…Well, almost that simple.

Today, the electronic controls and exhaust emissions aftertreatment systems have made things much more complicated. But they have also given us much more potential control of the entire machine, as well.

Tier 4 engines are controlled by an Electronic Control Module (ECM) that monitors engine RPM, intake air temperature and flow rate, exhaust temperature, coolant temperature, exhaust gases, turbo boost, and several other variables. All of this is done in order to create an efficient prime mover that generates minimal air pollution. Because these engines have to operate within some pretty strict parameters, each engine application has to be tested, monitored, and approved for each new application to ensure that the engine will live a long, useful, and trouble-free life.

The ECM of the Tier 4 engine communicates on a vehicle bus called J1939 that was established by the Society of Automotive Engineers. This communication network allows a Programmable Logic Controller (PLC) to communicate directly with the Tier 4 engine and all of a machine’s controls. By having a main controller communicate with and coordinate all functions, a machine’s operation can be optimized for safety, productivity, and efficiency…but it’s complicated and not many small to mid-size OEM’s have the in-house capability to do all the design and programming that is required to commission their machines.