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Transient-voltage-suppression diode

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Transients are temporary spikes or surges in  voltage or current  that can impact circuits in minor glitches to complete failure. A voltage transient can be anywhere from a few millivolts to thousands of volts, and they can last from nanoseconds to hundreds of milliseconds. Some transients are repetitive, such as those caused by inductive ringing in a motor, while other transients are more sporadic, such as ESD events. The symbol of TVS diode is as shown below. Circuit Connection   Reverse standoff voltage (V RM ) This voltage is also known as maximum working peak voltage.   This is the normal operating threshold voltage of the device. The TVS diode will appear as high impedance to the protected circuit when the applied voltage across the diode is less than this threshold. Reverse breakdown voltage (V BR ) This voltage is also known as breakdown voltage, this is the voltage threshold at which the TVS diode begins to conduct a specified amount of current. Voltage V BR  should

What is Ammeter | Definition, Types, Summary

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What is ammeter? Ammeter is a meter used to measure electric current flowing in a circuit. The unit of electric current is ampere hence the name ammeter (ampere +meter). The symbol of ammeter is as shown below. Ammeter is always connected in series with the circuit whose current is to be measured. In other words the current flows through the ammeter. As shown below. The ammeter consists of set of coils. These coils get deflected when current flows through them. Below are types of ammeter based on their construction and working. 1.       Permanent magnet moving coil 2.       Moving iron ammeter 3.       Electro dynamometer ammeter 4.       Rectifier ammeter Also ammeters are classified as AC ammeter and DC ammeter. Let us discuss every type in detail. 1.       Permanent magnet moving coil – here the coil comprises of a conductor and magnetic poles. Conductor is placed between the two magnetic poles. Whenever current flows through the coil the conductor gets deflec