Selective Catalytic Reduction (SCR), a process where a gaseous or liquid reductant (most commonly ammonia or urea) is added to the flue gas stream and is absorbed onto a catalyst. The reductant reacts with NOx in the flue gas to form H2O and N2.

Specialty Catalytic Converters are required to make an SCR system work, the current options being a Vanadium based catalyst, or a catalyst with Zeolites in the washcoat. In some jurisdictions use of a Vanadium based catalyst are frowned on (California) and the Zeolite type preferred, however Vanadium ....etc

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silicon control rectifier -scr

Content

Introduction
What is SCR ?
Characteristic of SCR
Two transistor analog connection
Series connection of SCR
Parallel connection of SCR
Advantages
Disadvantages
Conclusion

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sir i want the abstract of automatic battery charger using scr ....etc

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Battery charger circuit using SCR.


Description.

A simple battery charger based on SCR is shown here.Here the SCR rectifies the AC mains voltage to
charge the battery.When the battery connected to the charger gets discharged the battery voltage
gets dropped.This inhibits the forward biasing voltage from reaching the base of the transistor Q1
through R4 and D2.This switches off the transistor.When the transistor is turned OFF,the gate of
SCR (H1) gets the triggering voltage via R1 & D3.This makes the SCR ....etc

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BRIEF DESCRIPTION OF COMPONENTS:
1) Transformer:-
A transformer is a static device which consists of two or more stationary circuits interlinked by a common magnetic circuit for the purpose of transferring electrical energy between them.
• E.M.F equation of a transformer:
e=4.44Baft
B=maximum flux density in the magnetic circuit.
a=area of cross-section of the core.
f and t are frequency and no. of turns respectively.
• Step up and step down transformer:
A step up transformer is one whose secondary voltag ....etc

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Selective Catalytic Reduction (SCR), a process where a gaseous or liquid reductant (most commonly ammonia or urea) is added to the flue gas stream and is absorbed onto a catalyst. The reductant reacts with NOx in the flue gas to form H2O and N2.

Specialty Catalytic Converters are required to make an SCR system work, the current options being a Vanadium based catalyst, or a catalyst with Zeolites in the washcoat. In some jurisdictions use of a Vanadium based catalyst are frowned on (California) and the Zeolite type preferred, however Vanadium ....etc

[:=Read Full Message Here=:]

Selective Catalytic Reduction (SCR), a process where a gaseous or liquid reductant (most commonly ammonia or urea) is added to the flue gas stream and is absorbed onto a catalyst. The reductant reacts with NOx in the flue gas to form H2O and N2.

Specialty Catalytic Converters are required to make an SCR system work, the current options being a Vanadium based catalyst, or a catalyst with Zeolites in the washcoat. In some jurisdictions use of a Vanadium based catalyst are frowned on (California) and the Zeolite type preferred, however Vanadium ....etc

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PHASE-ANGLE CONTROL OF SCR USING AT89C51
Silicon-controlled rectifiers (SCR) are solidstate semiconductor devices that are usually used in power switching circuits. SCR controls the output signal by switching it ‘on’ or ‘off’, thereby controlling the power to the load in context. The two primary modes of SCR control are phase-angle fired-where a partial waveform is passed to regulate the power.
In the phase-angle controller, the firing pulse is delayed to turn on the SCR in middle of every half cycle. This ....etc

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SCR Applications
Resistor R1 limits the magnitude of the gate current.
When the SCR turns on, the anode-to cathode voltage (VF) will drop to the gate circuitry.
For the negative region of the input signal, the SCR will turn off since the anode is negative with respect to the cathode.
The diode D1 is included to prevent a reversal in the gate current.
Variable – Resistance Phase Control
A circuit capable of establishing a conduction angle between 90° and 180° is shown in Fig. 20.12a.
The circuit is similar to that of Fig ....etc

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I request you to send me the application areas of SCR phase angle control using AT89S52. What are the advantages and disadvantages of this method? In today's time, where is it used? What modifications can be made? Please mail the reply on [email protected] or [email protected]
Thank you. ....etc

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