Ratings of Circuit Breaker - Detaily Explained...

Short Circuit Breaking Current of Circuit Breaker :    This is the maximum short circuit current which a circuit breaker can withstand before it. Finally cleared by opening its contacts. When a short circuit flows through a circuit breaker, there would be...

What is Operating Sequence in Circuit Breaker ? What does O-0.3- CO- 3-CO Means ???

This is the Rated Operating Sequence (Duty Cycle) of the circuit breaker. Which denotes the sequence of opening and closing operations which the circuit breaker can perform under specified conditions. The operating mechanism experinces sever stress during the auto-reclosure...

What are the types of CT Cores... What does 5P20 Means...???

        CT's are categorized as Protection CT, Special Protection  CT and Measuring CT. Based on this, the CT's are  classified. Here is the meaning of the CT classes: Class 5P20:  The letter 'P' indicates it is a protection CT. The...

Importance of Substation Earthings - Detaily Explained

Functions of an Earthing System The two primary functions of a safe earthing system are i) ensure that person who is in the vicinity of earthed facilities during a fault is not exposed to the possibility of a fatal electrical shock, ii) provide a low impedance path...

What are the types of Class I, II, III, 0, 01 in Electrical Appliances ?

    Basically, a Portable appliance is given a Class rating by the manufacturer depending on how the user is protected from Electrical Shock.      Electrical appliances classes defined in IEC 61140, and are categorized into one of...

Why crest factor is so important in UPS ???

          The crest factor of an AC current waveform is the ratio of waveform’s peak value to its rms value:           crest factor = |peak current| / rms current The crest factor for a sinusoidal current waveform is...