2391-10 Written Exam - 01/12/11

[cr0ft]

Just sat this tonight. What does everyone that sat it tonight think of the paper?

 

[Jurasic Spark]

Q1 I think was the list on page 17 of GN 3?

Q4 was something along the lines of why do we do an initial verification:-
1, Confirm installation/circuit complies with designer's intentions
2, Designed, Installed and Inspected & Tested to comply with BS7671
3, Not damaged so as to impair safety
Just seen it in some notes, not sure where it came from though as nothing in GN3.

Don't you have to add a x1.2 correction factor to the volt drop formula to allow for the rise in temp when the circuit is under load?

Good luck to everyboby, only a couple of months to wait.

Q4 was something along the lines of why do we do an initial verification:-
1. All installed equipment complies to relevent standards.
2. Everything has been selected and erected in accordance with BS7671
3. No visual damage to impair safety
GN3 p17

 

[exnavysparks]

v drop Q.... was it.... (R1+RN) X Ib
0.38 ohms x 30A = 11.4 ???????

 

[SHOCKNOT]

Thats the answer i got 11.4, which i got to 4.95% so I think thats ok because all circuits you are allowed 5% except for lighting circuits (i think?).

 

[Banjo]

For the TN-C-S question i pit down Exibitions, shows and stands.

What did people put down for the max voltage on socket outlets with surge protection devices?

 

[firemanowl]

v drop Q.... was it.... (R1+RN) X Ib
0.38 ohms x 30A = 11.4 ???????

I think you have to apply a x1.2 correction factor to allow for the rise in temp when circuit under load?

 

[firemanowl]

250 v for surge protection

 

[Banjo]

250 v for surge protection

Good thats what i put. Then the next part of the question asked for wht are the test connections i put test between live conductors and live conductors to earth.

 

[firemanowl]

Thats what I put Banjo, i think it's only the test voltage that is different, the rest of the test is the same.

 

[fredrico]

Thats what i put Banjo. Is it a 60% pass mark for the exam? Its a total of 90 marks for section B and about 60 marks for section A ?? So you have to get 60% of 150 marks?? Also 1M ohm minimum resistance for the surge socket is what i put.

 

[Banjo]

I heard the pass mark floats at 60% to 70%, as they mark it so only a certain percentage pass i think. What didyou put for the question that asked the earth return parth on section A with TNCS, TNS & TT?

 

[firemanowl]

What test voltage did you put for the 25v question?

 

[Banjo]

What test voltage did you put for the 25v question?

I put 250v

 

[NMc]

There is no officially stated pass percentage by C&G. It is what is called floating. It depends upon a number of things, the main one being how hard the exam is deemed to be. As a general indicator you need to be aiming for 80% to be OK

 

[fredrico]

80%?? Thats me done for then.

 

[fredrico]

Look on the bright side, at least i have been promoted from Junior Member, to Member!!