In real life there are very often situations when it is necessary to test devices with non-linear parameters. In such cases, the use of a single measuring tool may not bring the desired result.
One typical example is Power line filter testing, the task of which is to filter out unexpected spikes in the supply network for homes or industries. Real loads are usually non-linear, namely a combination of inductive and capacitive loads coming on at unpredictable moments. Such loads cause unwanted harmonics in the power line, and it is therefore important to have reliable test results for filters designed to reduce harmonic distortion in the power lines. The presence of harmonics in the power grid can be cause equipment malfunctions, such as overloads in the neutral conductor, increased losses in transformers, disturbances in motor torque, etc.
Harmonic filters could be passive, active and combined. The most common solution, as also illustrated in the IEC EN 61642 standard, is to appropriately connect an inductive reactor in series with the capacitor. The inductor parameters must be adjusted to achieve a resonant frequency lower than the lowest harmonic frequency of the voltage present in the circuit.
The purpose of this article is not to paraphrase the testing techniques, they are well described in a number of documents. The main purpose is to show the possibility of creating a universal testing toolset on the example of the capabilities of one company - Computer Controls.
To solve such testing tasks Computer Controls together with well-known manufacturer GoodWill Instek offer a wide range of measuring equipment. For example, on the picture you can see:
The low cost GoodWill Instek MDO-2xxxA series of digital storage oscilloscopes has follow key features:
In addition to advanced oscilloscope specifications, the MDO-2000A series is also a dual-domain test platform. For frequency domain analysis, the spectrum analyzer measurement mode is provided to allow users to have frequency domain analysis with higher resolution.
Series of high-frequency LCR meter LCR-82xx, which has four models, and the maximum test frequency up to 30 MHz has follow key features:
The measurement results can be presented numerically or graphically according to the selected measurement mode, allowing users to optimally interpret the characteristics of the DUT. At the same time, a full range of standard interfaces such as USB device, RS-232C, Handler and GPIB allow users to control the instrument by the most familiar interface without worrying about additional hardware investment costs.
GW Instek recently introduced the flagship model (200VA output capacity) safety analyzer – the GPT-12000 series, which is the first safety analyzer in the world to comply with IEC 61010-2-034 (Safety requirement for electrical requirement for measurement, control and laboratory use – particular requirements for measurement equipment for insulation resistance and test equipment for electric strength), which stipulates that the requirements of the software and hardware interfaces must be followed while designing high voltage and insulation resistance test and measurement instruments so as to ensure that users are provided with necessary protection and warning while using the instruments.
It has follow key features:
The value of such a versatile tool as a digital multimeter does not need to be proven again. A precision inexpensive DMM is absolutely required in any laboratory and the DMM series GDM-906x can provide such parameters:
Such set of equipment can be used to solve the widest range of tasks. Moreover, replacing one device with another similar one with other characteristics expands this spectrum even more.