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) of the Philippine Electrical Code 2017 states that
Design analysis shall be included on the drawings or shall be submitted on separate sheets of standard size, and shall show:
(1) Branch circuits, sub-feeders, feeders, busways, and service entrance;
(2) Types, ratings, and trip settings of overload protective devices;
(3) Calculation of voltage drops.
(4) Calculation of short circuit current for determining the interrupting capacity of overcurrent protection device for residential, commercial, and industrial establishment;
(5) Protection coordination of overcurrent protective devices;
(6) Arc-flash Hazard Analysis to determine the required personal protective equipment (PPE) in other than dwelling place - (see Appendix H for PPE)
The Fine Print Note in this section, however, states
FPN No 1: This analysis is not required for dwelling units but required for service equipment and other electrical equipment not part of the individual dwelling units of residential condominiums and individual detached dwelling units.
What does this FPN mean?
Though FPNs are for information only, FPNs are supplementary to the rules in the PEC. This means that design analysis is not required for individual dwelling units however, design analysis is required for the multi-dwelling units main service equipment and conductors to support the electrical plans.