Answer / sharad

A soft starter is a solid state motor starter that is used
to start or stop a motor by notching the voltage waveform,
thereby, reducing the voltage to each phase of a motor and
gradually increasing the voltage until the motor gets up to
full voltage/speed all at a fixed frequency. The profile of
the increase of voltage depends on the application. The
voltage is reduced and controlled by 3 pairs of back-to-back
silicon-controlled rectifiers (SCRs), which are a type of
high speed thyristor. A soft starter takes the place of a
contactor and can also take the place of an overload relay
in a standard motor starting application.

I am getting above 60 V as open delta voltage against single phase unit ICT at tertiary delta formed and ICT getting trippped on NDR. ICT tested and found in order. PTs provided on tertiary are tested and in order. what may be the reason?

0 Answers  

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what is the method to calculate the voltage drop for number of meters Example 250volts I/p at one end if the cable length is 50 meters what could be the drop?, after 100 meters how much? needs formulae.

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How to know th details about an electrical Drawing ? Please mention the easy method.

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in the case of 6.6kv motor starter combination contain fuses on it VCB. but in 11KV motor starter combination Fuses are not using in it's VCB why?

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1 Answers   NK Power Systems, Reliance,

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Why we say three phase voltage 440v.

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is there any concept of armature reaction in Induction motor?

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why do we need transformers?

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why the field winding in dc motor is not short circuited eventhough dc supply is applied across the winding

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Can step down transformer works as step up one???

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Is a 300w induction motor used in a food processor as powerful as a 1000w DC motor.

0 Answers  

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What is online and offline ups? how does it works?

0 Answers   Call Centre,

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