The commonly used turbidimeters are as indicated below: 1. Jackson Turbidimeter (or Jackson Candle Turbidimeter): It consists of a graduated glass rube placed in a metal cylindrical container which is supported on a metal stand. At the bottom of the stand a standard candle of bees wax is fixed. The candle is so designed that it burns within the limits [...]
Complex waveforms are most accurately measured with a true rms reading voltmeter. This instrument indicates the rms value of any waveform (such as a sine wave, square wave or sawtooth wave) by using an rms detector that responds directly to the heating value of the input signal. To measure the rms value of an arbitrary waveform, we may feed an [...]
In this article we will discuss about the connection of an ammeter for measuring heavy current. When the line current is high, total current of the supply line cannot be sent through the coil of the ammeter. For carrying high current, the cross-section of the coil must be large, and it becomes very difficult to make coil of a conductor [...]
In this article we will discuss about the disadvantages of ampere-hour meters. Ampere-hour meter actually measures electrical energy in ampere-hour. It is equal to current in ampere flowing through the current coil of the meter multiplied by the time in hour during which the current flows. But as the B.O.T. unit of electrical energy is kilowatt-hour, the scale of the [...]
In this article we will discuss about the use of earth testing megger, explained with the help of an example. Earth testing megger has either three terminals or four terminals. The three terminals of the instrument are marked as E, P & C. In some instruments the word 'Earth' is used in place of E. The main earth electrode under [...]
In this article we will discuss about the commonly used D.C and A.C energy meters. 1. D.C. Energy Meters: (A) Ferranti Mercury Meter: It is a very commonly used energy meter of mercury ampere-hour type. The construction and connection of this meter are shown in fig. 68. Ferranti mercury meter consists of a disc revolving between two permanent magnets,—one acting [...]
After reading this article you will learn about:- 1. Description of a Transit Vernier Theodolite 2. Terms Used While Manipulating a Transit Theodolite 3. Fundamental Lines of a Transit Theodolite 4. Adjustments of a Theodolite. Description of a Transit Vernier Theodolite: [Figs. 9.1. a&b]: A transit vernier theodolite essentially consists of the following parts: 1. Levelling Head: This supports the [...]