Isolator or disconnectors, as the name indicates, is a switching or isolation device, intended to disconnect an equipment or electrical Circuit from the supply. It is an offload device, which means it can be operated only when the current passing through it is zero. Unlike circuit breakers, it lacks a built-in arc suppression system. It can be operated only during offload conditions. (more…)
Transformer action is a phenomenon by which EMF(Electro-motive force) is induced in from one coil to the other coil by electro magnetic induction. It is the basic principle of electric transformers.
MCB (Miniature circuit breaker) is a re-settable device designed to protect a circuit from short circuits and overcurrents. Trip curves of MCB's (B, C, D, K and Z curves) tell…
Stalling is a condition at which a motor stops rotating even when there is sufficient voltage at it’s terminals. This condition occurs when the torque required by the load is more than the maximum torque (Breakdown torque) that can be generated by the motor. At this condition, the motor drains the maximum current and the speed comes zero.
This is a very common question asked by those who are starting up with transformer science. You may come across the same question during interviews too. (more…)
MCCBs and RCCBs are circuit protection devices with two different application. When the former protect against overload and short circuit, the later protects against Residual currents and electric shock.
Contactors and relays are two closely related terms. Both of them are electrically operated switches used for control and switching of loads.
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