Electromechanical systems are present in a wide range of complex and sophisticated vehicles such as ships, ground vehicles, aircraft, and the like. The way such standard systems work is through the software that operates on a controller. The physical components and mechanics are thus regulated by the controller, enabling the vehicles’ moving parts.
HIL testing replicates actuality by transmitting real signals into a system from the controller into a simulated product. The controller operates at a typical pattern and does not change its behavior, rehearsing the pretended real-system process. Such a method enables sophisticated and high-risk equipment such as modern aircraft to conduct abundant tests before achieving the required high safety standards. These tests save time, money, and above all, make the equipment safer.
This guide will cover how-to setup Site Master: Measurement Type, Frequency, Amplitude, Markers, Limit Line, and DTF.
Anritsu’s handheld cable, antenna, and spectrum analyzer family, known as the Site Master series is designed for engineer’s in-field measurements.
This brief, basic guide will review some measurement setups involving the following models: S331E, S332E, S361E, and S362E.
The specific characteristics of a signal can be measured by a variety of instruments. For example, a counter can measure a signal’s frequency or its period, and an ac voltmeter can measure the RMS value of the signal. Although these instruments are very useful and can be more accurate than the oscilloscope, their application is mainly limited to the measurement of one parameter of the signal. With an oscilloscope, one can visualize the signal of interest and also observe whether the signal contains properties that would not be made apparent by most other instruments (for example, whether the signal is superimposed on a de level, or whether there are noise or relative hf oscillations present with the signal at the test point). Thus the oscilloscope is a more valuable instrument because it gives an exact visual representation of the signal waveform.
There are many different types of amplifiers. The first type to be discussed is operational amplifiers. These are also known as op-amps. Op-amps are integrated circuits where the chip contains the transistors of the stages and resistors and capacitors as well. An op-amp is a differential amplifier on a chip, in which most points in the circuit are accessible through terminal connections. The terminals can be linked, so different parts or all of the differential amplifier can be used for different functions. Since both stages of the differential amplifier produce opposite outputs, either stage can be used as an inverting or noninverting amplifier. Since the first stage feeds the second stage as an emitter follower, the emitter follower output can be used. It can be used with one or two inputs, or one or two differential or emitter-follower outputs. If external resistors for feedback or stabilization are added, the op-amp can also function as oscillators, gates, counters, and various others. Op-amps are used extensively in digital meters.
Multimeters are current meters, voltmeters, and ohmmeters contained in one case. There are separate current, voltage, and resistance circuits interconnected by switches and they share the same meter movement. A function switch is utilized to choose the type of measurement: position 1 is for de volts and resistance, position 2 is for de and ac current, and position 3 is for ac voltage. The jack on the right, the COMMON jack, is used for all measurements. For every type of measurement, the range switch is set for the correct scale reading. Positions I and 2 are resistance ranges, positions 3 to 6 are current shunt settings, and positions 7 to 9 are voltage multiplier settings. Rectifiers D1 and D3 are linked for ac current measurements and rectifiers D2 and D3 are used for ac voltage measurements. Fuse FI safeguards the meter movement from overload. Resistors R1, R2, R7, R8, and R9 are switched in and out of the circuit by the range switch. The current shunts, R3 to R6 are only linked into the circuit in position 2 of the function switch. The range switch then chooses portions of the ring shunt.
Whether you install, operate, repair, or design electrical equipment, you must know how to measure and test many types of electrical characteristics. The most imperative of these are electrical current, voltage, and resistance. Additionally, there are various applications that also require the testing and measuring of power, power factor, frequency, impedance, and sensitivity, as well as special component characteristics, such as capacitance and inductance.
For circuit operation, the variations between de and ac functions are not too dissimilar. For de signal voltages, the individual stages of the instrument are directly coupled. Direct coupling can also be used for ac voltage signals, but typically capacitors are used to pass only the ac signal voltages from one stage to another. The test indications for ac must be handled slightly differently because of the nature of ac waveforms and the different ways of describing their levels. One ac wave has average, effective (RMS), and peak values. The analog meter movement responds to the average ac value, but we all use the effective or RMS value to describe a waveform, such as 120-V ac line power. The ac meter is calibrated for the effective value, even though it reacts to the average value.
Displaying readings on an analog scale, where the digital characters are printed on the scale in the different locations that the pointer swings is not an issue. But, putting digits on a digital readout where different digits must share the same location, is more difficult. Three ways have been used: the solid character, the dot matrix, and the bar segments. The solid character can be the most pleasing way of displaying digits, but it is problematic since they must all share the same space. This was the way the servo wheels worked, and electrically, it was done with Nixie tubes. These used ten transparent in-line wafers enclosed in neon gas. Each wafer had electrodes in the shape of numerals, which glowed when the wafer was electrified. Although the unused wafers were still discernible while one wafer glowed, it was tolerable. The Nixie tube was used for years and can still be found on special equipment. However, this method is costly and the tubes are fragile.
Sampling is the taking of a specimen, or a part, to illustrate the whole. For example, when a ship’s cargo of sugar must be checked for the amount (%) of water in the sugar, specimens of the sugar are taken from various places in the ship. The more specimens are taken, the more information is available about the quality of the cargo overall. It is evident that to be 100% sure about the condition of the cargo, all the sugar present in the ship would have to be checked; however, this is not possible.