W e have had meters to assist us in our day-to-day activities for decades. They date back to the early 1800s and have helped us verify designs, check compliance to standards, teach students and to trouble shoot problems as well as many other functions. These meters came in all shapes and sizes, built into wooden boxes, and measured parameters such as temperature, volts, amps, resistance, capacitance, signal

strength, earth resistance, insulation resistance, light, and the list goes on and on. They were delicate and required gentle handling. The interpretation of the results from these meters was very subjective in the early days. We relied on the operator’s reading of the pointer position for which the viewing angle played a major role on the accuracy in the results. Temperature and humidity also played a major role in

the accuracy of the measurement. In many cases these two conditions accounted for as much as a 5 to 20% error in measurement.

A mirrored surface was incorporated behind the pointer right next to the scale in the early 1900s to assist the operator in reading the pointer position correctly. The operator could now line up the reflection of the pointer shaft with the scale marking and get a much better result.

It was still necessary for the operator to write down the measurement results in a notebook or on a pad or somewhere if they were to be used at a later date or in a report.

As time progressed two more developments occurred that advanced the measurement, interpretation and record keeping process.

One of these events was the development of the digital display. Now meters and instruments could present the measurement results directly in numeric form thus eliminating the interpolation errors of the past.

During this time the emergence of paper chart recorders began to gain wide acceptance. The meter movement became an ink pen that recorded the results on a paper chart. This gave us the ability to record results over time without the presence of an operator continuously looking at the meter for results and the first form of documentation of the measurements. Interpretation still remained an issue in that the ink traces were crude and sometimes bled over a wide area of the chart. Inking systems got better and eventually were replaced by thermal writing systems and finally with solid state printheads that added the ability for text to be printed as well as traces on the paper. Although this brought us into the modern era of measurement, data collection and reporting, it still left a lot to interpretation of data and manual report generation. The systems were big and not conducive for portable, hand held applications. Computers were big and expensive and not the ideal choice of meters.

In the late 1970s the microprocessor came on the scene. This development began the revelation of measuring instruments into what is now a measurement and reporting system both affordable and compact in size.

The first uses of microprocessors in metering added the ability to combine the functions of several instruments into one compact sized instrument. One example is the venerable clamp-on ammeter. Initially

they were only available to measure AC current and required a meter with a display to be attached to read out the measurement. Today they incorporate their own displays that can display both graphs and text and can measure all the parameters that were once the responsibility of the multimeter. Added to this is

the ability to compute results from the measurements taken by the meter. For example, AC voltage and current can be measured and power can be calculated from these measurements and displayed and recorded in the meter. Phase angles can be calculated and in-rush current can be recorded. Even phase rotation can be computed and displayed all in a device that fits into your shirt pocket. As computer systems advanced and the cost and size of memory chips came down, these devices found their way into every type of modern instrument. Communication techniques improved in both reliability and speed making it now practical

to send large amounts of data from the instrument to the computer and for the computer to configure the instrument and even calibrate the instrument on an as needed basis.

Today the 21st century versions of those early meters that measured temperature, volts, amps, resistance, capacitance, signal strength, earth resistance, insulation resistance, light etc. now measure, compute, record and report results with amazing speed and accuracy. Gone are the days of interpreting measurements,

hand calculating and writing down results and generating reports. Mulitmeters, Megohmmeters,

Clamp-on meters, Ground Resistance meters, Oscilloscopes and Power Analyzers now come standard with adequate internal memory to store hundreds of thousands to millions of test data points. They incorporate displays that clearly present the measurements and computational results with crystal clear accuracy without interpretation errors.

They communicate with computer systems and PDAs via RS-232 or USB connections or wireless using technologies such as Bluetooth. Now you don’t even need to go to the job site to collect the data on some instruments, just retrieve it using the internet and your web browser.

These intelligent meters come with application software to store and graph the collected data and to print out reports from pre-defined templates or allow the user to custom design his or her own report templates.

Configuring the instrument to measure, compute and record exactly what you want is also a standard feature of today’s instrument and software. Comparing newly collected data with historic data from a week or a month or a year ago is effortless and judgments and corrective actions are far more accurate today than they were “back in the day”.

Even the lower end instruments today can store data and send it to the computer allowing the user to incorporate spreadsheet software or other application packages to generate their own reports.

When looking for a new meter, you owe it to yourself to look at these intelligent meters with automatic report generation capability. You will be impressed with these features capability and pleased with the cost of ownership not only from the purchase price but the time savings as well. ❑