Instrument Transformer-Current Transformer and Voltage Transformer

Instrument transformer are special type of transformer. Because we use them to increase range of ordinary ammeters and voltmeters. We use them in AC system measurement for measurement of electrical quantities. It also find it application in protective relays for the protection of power system. The basic function of instrument transformer is to step down … Read more Instrument Transformer-Current Transformer and Voltage Transformer

Synchroscope Construction and Working

Electrodynamic synchroscope

Synchroscope is used to synchronize two alternators. Synchronize means that the machine of equal frequency and voltage are operating parallel to each other. We connect the alternator in parallel with one another with bus bar to shore the load. In electrical power system, a synchroscope is a device which indicates the degree to which two … Read more Synchroscope Construction and Working

Galvanometer Type Measuring Instrument

Galvanometer is a basic electrical instrument. We use it to detect current in a circuit. Sometimes for measuring their magnitude also. PRINCIPLE OF OPERATION OF GALVANOMETER It works on the principle of conversion of electrical energy into mechanical energy. When we place a current carrying conductor in a magnetic field. Then it experiences a force. … Read more Galvanometer Type Measuring Instrument

Difference Between Moving Iron and Moving Coil

The basic difference between the Moving iron and Moving coil instruments is that. A moving iron instruments uses a soft iron whereas moving coil instrument uses a coil as moving mechanism. Comparison Table Properties Moving Iron Moving Coil Construction Iron is used as moving mechanism Conductor Coil is used as Moving mechanism Working Principle Magnetism … Read more Difference Between Moving Iron and Moving Coil

Dynamometer Type Instrument Construction and Working

DYNAMOMETER TYPE WATTMETER

Dynamometer type measuring instruments are similar to PMMC instrument. Except that the permanent magnetic field coil is replaced by a coil which carries the current to be measured. Such instruments may also serve as transfer instruments. A transfer instrument is that which may be calibrated with dc source and then used on ac without any … Read more Dynamometer Type Instrument Construction and Working

Permanent Magnet Moving Coil Instruments-PMMC Instruments

As we know that there are different types of measuring instruments which we had discussed in previous articles. In this article we will discuss one of the type of moving coil instrument which is permanent magnet moving coil type instrument. What is Moving Coil Instrument The coil rotates between the magnetic field of a permanent magnet … Read more Permanent Magnet Moving Coil Instruments-PMMC Instruments

MOVING IRON INSTRUMENTS

As we know that there are two types of measuring instruments named moving iron and moving coil which we have discussed in  article. In this article, we will discuss moving iron instruments. These instruments are widely used in laboratories and switchboards at commercial frequencies. Because these are cheaper in cost, robust in construction and can … Read more MOVING IRON INSTRUMENTS

TYPES OF MEASURING INSTRUMENTS

Some of the instruments are used for dc measurements only and some are used for ac measurements only. Some are used for dc as well as ac measurements. In this article we will be discussing about types of measuring instruments. DC MEASURING INSTRUMENTS The instruments, whose deflections are proportional to the current or voltage under … Read more TYPES OF MEASURING INSTRUMENTS