After a two-year hiatus due to Covid, Weschler Instruments resumed its normal trade show and conference schedule in 2022. The major event for the year was the IEEE Transmission & Distribution Conference in New Orleans on April 25-28. (more…)
Instrumentation Switches Explained
An instrumentation switch (or instrument switch) is a special-purpose switch used in conjunction with an electrical meter in a control panel. It allows a single meter to read multiple circuits. The most common application is monitoring three-phase ac power systems. The meter is switched into the circuit to make a measurement. (more…)
Advantages of An Analog Multimeter
The Simpson 260 has been an industry-standard multimeter for over 70 years. It is now available in 13 versions including industrial, ruggedized, safety rated, and high accuracy models. Why is this analog product still used, despite the abundance of digital multimeters? More generally, what advantages does an analog meter have compared to its digital counterpart? (more…)
AC Current Instrumentation
Last month’s posting covered the popular methods for sensing AC current (shunt, current transformer, Hall sensor, Rogowski coil). Here we will review some of the instruments available for fixed, portable, local and remote AC measurements. (more…)
AC Current Measurement Methods
There are two general methods for measuring ac currents:
- by direct connection with the current-carrying circuit
- by utilizing the magnetic field or flux generated by the current