Engine Load Testing And Its Importance

Engines, particularly diesel ones, are expensive and known to have a long lifespan. Engines

are built to run within an environment and load limit. However, the improper operation

conditions often kill the engines prematurely. Overload is one of the top three common

reasons [1]. An overloaded engine cannot reach its rated Revolutions per Minute (RPM)

under a full load of fuel and water tanks capacity [2]. Continued operation of an overloaded

engine leads to excessive black smoke emission during cruising, high exhaust temperature

beyond manufacturer’s specification, excessive fuel consumption, slow acceleration,

reduced engine life, and exhaust flow components failure.

Engine RPM denotes the number of times the engine crankshaft rotates around its axis and

translates to the torque or power produced. The piston movements during engine cylinder

combustion drive the crankshaft’s rotational motion [3]. In engine commissioning test, the

RPM test is one of the tests to ensure that the end user complies with the engine build

specifications.

The engine RPM measurement involves the measurement of the crankshaft gear's

rotational speed. This gear contains a fixed number of teeth (Figure 1.0).

Figure 1.0 Crankshaft gear with fixed teeth

Conventional Engine RPM Measurement Methods

There are two conventional methods of measuring RPM [4] before proximity sensors'

ii) Stroboscopic using intense flash that strobes at high frequency. The measured

rotating object will appear to be stationary when the frequency of the

light synchronized with the RPM of the object. It takes multiple adjustments to

get the synchronized frequency and requires manual logging of the result.