Combining the Best of Analog and Digital Indication
Measurements of process parameters have historically been accomplished by the analog panel meter (APM). As processes evolved, a need arose for more accuracy in readings. This led to the development of the digital panel meter (DPM). However, operators still preferred an APM for a quick indication of relative signal level. When a process condition became critical, a DPM was then used for more exact readings. The Digital Bargraph Meter was developed to combine the best features of analog and digital indication. This article reviews the development of bargraph meters and their use today in a variety of monitoring and control applications.