Course Content
Electricity Refresher
As we are obviously using electricity to test our electrical equipment, it makes sense that we need to understand what electricity is and how it works. This is a brief section, as anyone carrying out 'PAT Testing' should already have a good understanding.
Environment Check
"The safety of electrical equipment is directly related to the environment it is being used in". A perfect item could still be unsafe if it is being used in the wrong environment.
User Check
Electrical equipment is often very safe, until it is put in the hands of the user of the equipment. Potentially, the user of the equipment has a greater responsibility, especially if they are using it on a regular basis.
Equipment Construction
Not every piece of electrical equipment is the same. Obviously they have different jobs to do, but what about the safety features built into them? We need to understand what safety features should be present prior to deciding what tests we need to carry out.
Formal Visual Inspection
Around 90% of electrical equipment which fails a 'PAT Test' will fail due to physical defects. Arguably, the formal visual inspection is more important than the electrical tests.
Electrical Tests
The test device acts like an x-ray machine... it gets to the parts of the electrical equipment which we can't usually get to, without taking the item to pieces. The tests we carry out vary from item to item and must be carried out correctly and in the right order.
Interpreting Test Results
Your test device says the electrical equipment has 'passed', but does the test device know everything about the item being tested? Unlikely, so it is up to you to check the results against industry standards.
Recording Results & Labelling
What if there is an incident and someone gets hurt? Your paperwork is evidence of due diligence, but only if it is filled out accurately.
Final Exam
Hopefully the previous topics and your prior knowledge of 'PAT Testing' will have prepared you for your final test. There are no trick questions, but they are not that easy either. Take your time and remember to READ THE QUESTION.
PAT Testing Online Refresher Course
About Lesson

An electric current is a stream of charged particles, such as electrons or ions, moving through an electrical conductor or space. In electric circuits the charge carriers are often electrons moving through a wire.

The SI unit of electric current is the ampere (symbol: A), or amp, which is the flow of electric charge across a surface at the rate of one coulomb per second.

To keep things simple, we will say that current is the flow of electricity, measured in Amps (A).  

When you plug an item of electrical equipment with a BS1363 plug into a standard BS1363 socket on the wall, we have 13 Amps available to us (although technically we have more, depending upon the size of the breaker in the distribution board).  However, the item isn’t greedy and will only take as much current as it needs in order to operate i.e. if it only needs 1 Amp, it will take 1 Amp, but if it needs all 13 Amps, it will take all 13 Amps.

Q. What happens to the flex when the item draws it’s required current from the socket and through the flex?  

A. The flex will get warm, due to resistance in the copper wire of the flex.

If the flex is going to get warm, what can we do to stop it from setting on fire?  Well, firstly the manufacturer should attach a flex which is able to carry the required amount of current without getting too warm.  Secondly, we put a fuse in the plug.  This is a ‘sacrificial device’ which is calibrated to break (and cut the circuit) if more than a specified amount of current passes through it.  In simple terms, if the electrical equipment is going to draw 2 Amps under normal operation, the flex could be rated at 3 Amps (better than we need) and fused at 3 Amps.  If the device develops a fault and draws too much current (more than 3 Amps), the fuse will ‘see’ the problem and break before the excess current passes into the flex and causing a fire.

Therefore, the BS1362 fuse in the plug has one job to do… protect the flex

Q. What rating of plug fuses do we have available to us?

A. Officially we have 3 Amp (red) and 13 Amp (brown) BS1362 plug fuses available to us.  Over the years, 1 Amp, 2 Amp, 5 Amp, 7 Amp and 10 Amp BS1362 fuses have been added to the list…each of which is coloured black.

Exercise Files
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