BS7671:2018+A2:2022 Let’s take a quick run through the new 18th Edition Wiring Regulations book, which includes Amendment 2 that was introduced in March 2022, BS7671:2018+A2:2022. We’ll go into more detail and get you ready to pass your 18th Edition exam when we go through the book together fully
READ MORELet’s take a look at what are possibly the three most used calculations within the 18th Edition Wiring Regulations for electrical installations. Calculation Voltage Drop Calculating the cross-sectional area of protective conductors Tabulated current carrying capacity of conductors ‘It’ 1. Calculating voltage drop… You won’t find this formula
READ MOREOne of the main reasons for using an alternating current a.c. supply is that we can easily change the voltage levels up or down by using a transformer which would be more difficult and expensive to do if using direct current d.c For efficient transmission the generated a.c.
READ MORE05: Cable Size and Protective Device Selection The cable most commonly used in domestic electrical installations is the 70 °C thermoplastic PVC insulated and sheathed flat cable which is often referred to as ‘Twin and Earth’ or ‘T&E’ and is available in various sizes ranging from 1.0 mm²
READ MORE01: Ohm’s Law Ohm’s law is one of the most important theories and a corner stone principle of the electrical industry. We are going to have a look at what Ohm’s law is and how it applies to the electrical world. Firstly, let’s look at the 3 key
READ MORETo become an approved domestic electrical installer who can self-certify their own work you will need to be a member of a Competent Person’s Scheme. Published in 2020 and in effect from September 2021 the IET Electrotechnical Assessment Specification sets out the minimum requirements to be met by
READ MOREInsulation resistance testing on a new installation(i.e. during initial verification) The object of this test is to verify that the quality of the insulation surrounding the conductors is satisfactory and has not deteriorated or been damaged causing short-circuits and earth faults. It is done at the consumer unit
READ MOREContinuity of Ring Final Circuit Conductors The objective of this dead test is to ensure that all ring circuit conductors are continuous throughout the ring, with no breaks and no interconnections and also that all connections are electrically and mechanically sound. This test also verifies the polarity of
READ MOREIntroduction… Initial Verification: Dead testing must be completed after your inspection and always before any live testing takes place. This is to ensure that all safety systems such as the main earthing, main bonding and all circuit protective conductors are in place and that there is no risk
READ MOREHow to connect a 2-way lighting circuit… When a single light needs to be switched on and off from two positions such as on stairs or landings a two-way lighting switch arrangement can be used. The most common and easiest way of doing this is to link both
READ MORE