Periodic Electrical Installation Inspection – What to Inspect? 

By on

This is the second post in a series of two on periodic electrical inspections. In the first post, I discussed how often inspections should be carried out. If you missed that post, you may want to read it now:

Periodic Electrical Installation Inspection
– How Often?

As with how often, when looking at what to inspect there are two considerations – 1) inspection of systems, which businesses themselves have decided are critical to their operation and 2) the minimum systems which need to be inspected according to regulations.

The aim of any inspection is to ensure that the equipment is still maintaining the safety of persons, protecting equipment and property, providing the correct level of business continuity and has not been damaged or subject to defects.

Regulations such as the IEE Wiring Regulations in the UK and the National Electric code in the US give guidance on the level and detail of the inspection. Regulations tend to deal predominately with the safety of persons and property. Depending on the nature of the installation, it may be prudent for the owner to go beyond regulation by carrying out additional inspections to ensure business continuity.

Inspections will consist of visual investigations, supplemented by testing (for example checking the disconnection of times of protective relays).

  • In the UK, IEE Guidance Note 3, Inspection & Testing, lists items which should be considered for inclusion in any inspection and testing routine:
    • Inspection – joints, conductors , switchgear, fire barriers, extra low voltage systems, basic protection, protective devices, enclosures, marking and labelling
    • Testing – protective/bonding/ring-circuit conductor continuity, insulations resistance, polarity, earth electrode resistance, earth fault loop impedance and functional tests (RCD, circuit breakers)

In determining the extent of inspection and testing, considerable care needs to be taken to ensure everything is covered. On large installations, inspection and testing may cover a sample of the system – with subsequent inspections covering different portions of the system.

Inspections and testing will be carried out around live equipment and only suitably qualified personnel should be doing this work. Records and test results should be kept to verify that periodic inspections have been carried. Inspection and testing records can also be compared across time to evaluate changes in systems and aid in planning maintenance.



Steven McFadyen's avatar Steven McFadyen

Steven has over twenty five years experience working on some of the largest construction projects. He has a deep technical understanding of electrical engineering and is keen to share this knowledge. About the author

myElectrical Engineering

comments powered by Disqus



UPS - Uninterruptible Power Supply

A UPS is an uninterruptible power supply.  It is a device which maintains a continuous supply of electrical power, even in the event of failure of the...

Post Editing Tips

If you at all familiar with programs like office and outlook, then adding and editing posts is pretty straightforward and intuitive.  However, there are...

Electromechanical Relays

Electromechanical relays have been the traditional backbone of electrical protection systems.  While over recent years these have been replaced by microprocessor...

Power Transformers - An Introduction

One of the fundamental requirements of an alternating current distribution systems it to have the ability to change the magnitude of voltages.  It is more...

Aluminium Windings - Dry Type Transformers

The other day I was talking to a colleague who is a building services consultant.  Despite regularly specifying dry-type/cast resin transformers he was...

Motor Efficiency Classification

Electric motors are one of the most widely used items of electrical equipment. Improving motor efficiency benefits include, reduced power demand, lower...

Paternoster Lifts

These lifts were first built in 1884 by J. E. Hall and called a paternoster ("Our Father", the first two words of the Lord's Prayer in Latin) due to its...

Battery Sizing

This article gives an introduction to IEEE 485 method for the selection and calculation of battery capacity.

Induction Motor Equivalent Circuit

Induction motors are frequently used in both industrial and domestic applications.  Within the induction motor, an electrical current in the rotor is induced...

Maximum Demand for Buildings

Estimating maximum demand is a topic frequently discussed. Working out how much power to allow for a building can be very subjective . Allowing too much...

Have some knowledge to share

If you have some expert knowledge or experience, why not consider sharing this with our community.  

By writing an electrical note, you will be educating our users and at the same time promoting your expertise within the engineering community.

To get started and understand our policy, you can read our How to Write an Electrical Note