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1.0 Educator of the Year Award 1

Lecture1.1


2.0 The Distinguished Gentlemen's Ride 1

Lecture2.1


3.0 Start Here! 1
A good place to start, vital information!

Lecture3.1


4.0 Men System 4
What is the MEN system, special considerations for outbuildings

Lecture4.1

Quiz4.1

Lecture4.2

Quiz4.2


5.0 Circuit Design 7
Maximum demand calculations, coordination of circuits, current carrying capacity, voltage drop

Lecture5.1

Quiz5.1

Lecture5.2

Quiz5.2

Lecture5.3

Lecture5.4

Quiz5.3


6.0 Circuit Protection 12
Short circuit temp rise, discrimination, fuse and circuit breakers, prospective fault current, fault loop impedance

Lecture6.1

Quiz6.1

Lecture6.2

Quiz6.2

Lecture6.3

Quiz6.3

Lecture6.4

Quiz6.4

Lecture6.5

Lecture6.6

Lecture6.7

Quiz6.5


7.0 Legislation and Standards 5
A guide to looking at legislation and standards

Lecture7.1

Lecture7.2

Lecture7.3

Lecture7.4

Lecture7.5


8.0 Testing 18
Testing requirements, associated methods and safety

Lecture8.1

Lecture8.2

Lecture8.3

Quiz8.1

Lecture8.4

Lecture8.5

Quiz8.2

Lecture8.6

Lecture8.7

Quiz8.3

Lecture8.8

Quiz8.4

Lecture8.9

Lecture8.10

Lecture8.11

Lecture8.12

Lecture8.13

Lecture8.14


9.0 Other Theory 2

Lecture9.1

Lecture9.2


10.0 Examination Questions 10
Test yourself with these questions, they are more in depth than the quizzes.

Lecture10.1

Lecture10.2

Lecture10.3

Lecture10.4

Lecture10.5

Lecture10.6

Lecture10.7

Lecture10.8

Lecture10.9

Lecture10.10


11.0 Wrap Up 1
Finishing up

Lecture11.1


11.0 Armchair Observations  Just my opinions! 8

Lecture12.1

Lecture12.2

Lecture12.3

Lecture12.4

Lecture12.5

Lecture12.6

Lecture12.7

Lecture12.8

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In reference to the last question on exam 1 and 3 just wondering why you have calculated the Rphe by multiping 0.8 rather than 0.64?

Hi,
Good question referring to Exam 1 Q3 & Exam 3 Q3. A bit of background first. The Rphe from Table 8.2 is calculated by taking 64% of Zs from Table 8.1 which are live figures, this is because for a dead test we are not measuring the supply so a reduction of 80% also the cables will be “cold” assuming 20 Deg C so a further reduction of 80%, hence 0.8 x 0.8 = 0.64 or 64%. Now back to the exam questions. In this question we are just looking at the final circuit hence we can forget about the 80% for supply. We do however need to have a reduction of 80% for the cables from Tables 34 or 35 as these tables are for live conductors, we know they are live as these tables are “A.C. Resistance (Rc) at 50Hz” if they are at 50Hz then they must be live. So, we make them the equivalent of dead figures by applying an 80% reduction. So there it is, instead of 64% due to supply and live conductors just 80% as we are not including the supply but making the live cable figures cold or dead.
Hope I haven’t confused you, read it through a few times and if you are still having a few problems I’ll make a short video explaining it.
Cheers, Brett


hello, in these problems you assumed Rph = Zph, so does this mean you didn’t take cable reactance (T42) into consideration? Why wouldn’t you include reactance?
Regards Mike
This has been the bane of my teaching FLZ and PFC. Please look at lesson 6.5 “Important – Before we start looking at FLZ and PFC calcs” it will explain why and you will need to check your training organisation for the method they use. Sorry, but a lot of training organisations are not aligned in this matter.

4 Comments
In reference to the last question on exam 1 and 3 just wondering why you have calculated the Rphe by multiping 0.8 rather than 0.64?
Hi,
Good question referring to Exam 1 Q3 & Exam 3 Q3. A bit of background first. The Rphe from Table 8.2 is calculated by taking 64% of Zs from Table 8.1 which are live figures, this is because for a dead test we are not measuring the supply so a reduction of 80% also the cables will be “cold” assuming 20 Deg C so a further reduction of 80%, hence 0.8 x 0.8 = 0.64 or 64%. Now back to the exam questions. In this question we are just looking at the final circuit hence we can forget about the 80% for supply. We do however need to have a reduction of 80% for the cables from Tables 34 or 35 as these tables are for live conductors, we know they are live as these tables are “A.C. Resistance (Rc) at 50Hz” if they are at 50Hz then they must be live. So, we make them the equivalent of dead figures by applying an 80% reduction. So there it is, instead of 64% due to supply and live conductors just 80% as we are not including the supply but making the live cable figures cold or dead.
Hope I haven’t confused you, read it through a few times and if you are still having a few problems I’ll make a short video explaining it.
Cheers, Brett
hello, in these problems you assumed Rph = Zph, so does this mean you didn’t take cable reactance (T42) into consideration? Why wouldn’t you include reactance?
Regards Mike
This has been the bane of my teaching FLZ and PFC. Please look at lesson 6.5 “Important – Before we start looking at FLZ and PFC calcs” it will explain why and you will need to check your training organisation for the method they use. Sorry, but a lot of training organisations are not aligned in this matter.