Portable machine analyzers

Portable data collectors, PDCs, are similar to check sheets in that they can be easily moved around. In injection molding, these devices are often referred to as portable machine analyzers, PMAs. They have some important advantages ... 

A simple DAS is a chart recorder that can track important variables like screw speed, diehead pressure, melt temperature, motor amperage, etc. More useful is a computer-based DAS these come in two forms portable data collectors/machine analyzers and fixed-station data acquisition system. 

Portable sound level meters are also available which can measure percentiles. These either hold the results in a memory which can be separately interrogated or may be connected to a computer for a printout. Larger machines (known as environmental noise analyzers) are available which can record percentiles and Leq readings and produce a printout. These are resistant to weather and can be left on-site for up to a week. 

Computers may be used for noise analysis when connected to dedicated hardware devices. One machine incorporates a narrow-band analyzer, octave and one-third octaves with all the features of an environmental noise analyzer. These devices cost much less than purchasing all the dedicated instmments separately. They may be obtained in portable form but are rarely weatherproofed for outdoor use. 

Vibration data are obtained by the following procedure (1) mounting a transducer onto the machinery at various locations, typically machine housing and bearing caps, and (2) using a portable data-gathering device, referred to as a vibration monitor or analyzer, to connect to the transducer to obtain vibration readings. 

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