Sound pressure levels were measured by using four 1/2 inch Bruel and Kjaer 4189-type free-field microphones located 1 m away from the longitudinal centers of the vertical planes forming the smallest rectangle which completely encloses the bare engine
While the bare engine
weights 24 kilos, the weight of the complete unit jumps up to 47 kilos.
* Gross horsepower: Power measured at the flywheel of a bare engine
or a stripped engine not installed in a tractor; the engine is equipped only with the parts needed to make it run.
"We believe we have helped our OEM customers on two fronts; to meet the new noise directives by reducing bare engine
noise and to establish a new quality benchmark in terms of how equipment actually sounds in operation."
With noise a factor in all markets, but especially in Europe and Asia, Perkins said the new combustion technology, in conjunction with mechanical enhancements, has helped lower bare engine
noise in excess of 3 dB(A) and as much as 5 dB(A) at the top of the four- and six-cylinder range, further, subjective noise at idle is improved, traditionally a yardstick for equipment manufacturers.
Perkins said at full load, bare engine
noise has been reduced by an average of 1.6 dB(A) across its full range of running speeds.
noise has been reduced with the help of the specially designed CTD fuel injection pump and developments in the combustion chamber design.
Both models are also available as bare engines
, designed for easy packaging with generators.
At the end of the assembly process in the various production plants, before assembling of the accessories required for Iveco's vehicular applications, the bare engines
for power generation and marine applications, as well as the ones sold on the open market to the various OEMs, are muted to the Pregnana Milanese plant.