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Is anyone familiar with the use of devices (such as SDH) to introduce delays into the transmission time for data associated with current differential protection to synchronise this data when different communication paths are being used by the relays at each end of the protected line (eg when...

Hi, For a large motor (5MW) supplied from an 11kV bus connected to a 36MVA generator is it advantageous to also disconnect the motor should the generator CB fail to trip for a fault on the 11kV bus and is this common practice? If the motor remains connected to the fault will its contribution...

I am looking at an surface mining installation which has a 66/22kV substation suppling a large mobile electrical load (5-10MVA) via a 22kV above ground cable (max 2.5 miles long). The cable earth is connected to the 22kV neutral at the substation. The mobile load has operators and there is no...

Would anyone know what the operating time characteristics (and setting ranges) of a MOC-7B-D distribution protection relay are. I am not sure but I suspect the MOC-7B-D is a Mitsubishi IDMT Overcurrent device. Thanks

I have a substation Single Line Diagram that indicates the protection on the 11kV circuits (which I would have expected to be Overcurrent + Earth Fault ie 50, 51, 50N, 51N) is "ICPT". Can anyone help me identify what this is as I am unfamiliar with the term? Many thanks.

Does using a larger motor for the same load cause it to run at a lower power factor and result in a lower power consumption. If so what are the disadvantages of doing this which deter it from being a common practice.

I am trying to understand a problem that was explained to me in rather vague terms concerning condensation in electrical induction motors operating in a refrigerated room (15deg C). I understand the motors run continuously, 3x8hr shifts, and are sealed units (would this be correct?) but require...

I have been browsing this forum to gain an appreciation of motor circuit protection in an attempt to broaden my knowledge. It appears to me that motors are supplied from a MCC (Motor Control Cubicle/Centres?) which may be up to say 100m from the motor. The motor has a thermal overload...