The Effect of Earthing Methods
Earthing the System Neutral Most earthed systems employ some method of earthing the system neutral at one or more points. Effectively Earthed System A system is effectively earthed when the …
Normative and Informative Annexes Compliance
The terms ‘normative’ and ‘informative’ are commonly used in IEC and other derivative standards to define applications of annexes. A normative annex is an integral part of a Standard which …
Philippine Electrical Code – Number of Supplies
Section 2.25.2.1 of the Philippine Electrical Code specifies that incoming supply to a building or other structure shall be supplied by only one feeder. 2.25.2.1 Number of Supplies. Number of …
Skin Effect Derating Factor on Conductor Ampacity
What is Skin Effect? The skin effect refers to the tendency of an alternating current (AC) to become distributed non-uniformly within a conductor, such that the current density is higher …
When Standards is Withdrawn
When a Current Standard is not Available Engineers are dependent on standards to ensure that their designs are compliant to the current standards.The dilemma of engineers is when the current …
Philipine Electrical Code – Is Design Analysis Required for Dwelling Units?
The Philippine Electrical Code has provisions for safe and reliable application of overcurrent protective devices based on short circuit study and a selective coordination study. Design Analysis Requirement Section 1.3.2.1(F) …