Why do you need to have an Electrical System Design Analysis?

Electrical Design Analysis is the investigation of an existing electrical system or an electrical design for implementation to verify the capacity of the electrical system to function reliably and safely during normal and emergency scenarios. This is used to ensure that electrical hazards and malfunctions are mitigated to promote safety of the building occupants and support continuity of business occupying spaces on the building.

The minimum scope of the design analysis as required by the Philippine Electrical Code (PEC) and mandated by respective Local Government Units (LGUs) thru their Office of the Building Official (OBO) are as follows:

· Calculation of Branch Circuits, sub-feeders, feeders, busways, and service entrance

· Types, ratings and trip settings of overload protective devices

· Calculations of short circuit current for determining the interrupting capacity of overcurrent protection devices

· Calculation of voltage drops

Here are the reasons why there is a need to have a design analysis on every building being constructed:

SAFETY

Design Analysis is used to confirm adequacy of sizing and specifications of electrical components such as transformers, cables, and circuit breakers mitigating overload problems. The Professional Electrical Engineer need to perform proper calculation of circuit currents in the electrical system to be able to size and specify electrical equipment and components needed to operate and protect the electrical system.

This way, safety of the people and the equipment used in the building is ensured. The system may further be confirmed by asking your Professional Electrical Engineer to perform Arc Flash Hazard Analysis on your system.

RELIABILITY

After confirming the proper size of the Over-current protective device (OCPD), the Professional Electrical Engineer then needs to provide proper settings of the OCPD. During fault scenarios, the OCPDs must be confirmed to be:

· fast to open the circuit so as not to cause damage to the equipment,

· sensitive to trip the least possible electrical fault in the system,

· selective to trip the circuit that is only affected by the fault, and

· reliable to protect the whole system.

SELECTIVITY

Protection Coordination study is part of the design analysis. This is to ensure that OCPDs are reliable and selective in tripping the circuit that is affected by the fault while securing continuous operation of other circuits in the system. The professional electrical engineer provides a TCC (time-current coordination) curve with proper settings to ensure that protection devices are properly coordinated.

POWER QUALITY

Ensuring that power delivered up to the end circuits are suitable for use of user equipment is another part of the Design Analysis. This is done by checking the voltage drops on every circuit and confirm that the drop is within the limits as required by all the equipment and electronic devices to be plugged-in to the system.

COMPLIANCE

As part of the requirements for the issuance of Building and construction permits, the local government units (LGU) requires submission of design analysis as per the Philippine Electrical Code signed and sealed by a Professional Electrical Engineer.

For existing establishments, it is required to update the design analysis of the electrical system prior to every modification to the system in order to maintain the reliability and security of the electrical system.

If there are no modifications made, it is recommended to have an updated design analysis to maintain the reliability and security of the system based on the changes in the utility power system.

Sigma Engineering is comprised of competent licensed Professional Electrical Engineers who caters inquiries for design analysis for both the new “for construction” buildings and the existing buildings. They confirm that your building’s electrical design is safe, reliable, and complying with the local and international standards. This enables you to focus more on your business without much worrying on your system.

Improve your business continuity and promote public security, consult your licensed Professional Electrical Engineer.

For more details, contact us.