June 2011 2391 exam

[Richard]

Did any of you sit it? I didn't think it was TOO bad, couple of questions I was a little unsure of but overall ok. How did you guys find it? I can never think of the bloddy questions afterwards!

 

[Jurasic Spark]

Q5)

State three inspection checks that may be carried out on an armoured cable installation using the sense of touch?​

Any answers?​

Q11)
State the effect on measured values of insulation resisLance of a230 V circuit if an​

insulation resistance test is carried out

i) between live conductors to earth with a tungsten lamp in circuit

ii)between live conductors with a switched fused connection unit, having a
neon indicator. left in the off position.

Any answers?

i) The instrument would display a dead short, reading through the filament.
ii) In the off position it would not effect the reading.

 

[Jurasic Spark]

Q14) State the minimum degree of lP code protection to be afforded by the

a) front surface of a distribution board?......IP2X?

b) horizontal top surface of a motor starter which is accessible?......IP4X?

c) front surface of a conduit box contain ing live terminals?......IP2X?



Q16) State the test instrument to be used to carry out a resistance measurement of an earth electrode

a)that forms part of a TT system that ls protected by a 100'mA RCD? Earth fault loop impedance tester?

b)used to earth a three phase transformer? Earth fault loop impedance tester?

c)used to earth a generator? Earth eclectrode tester?

b) Earth electrode resistance tester

 

[Jurasic Spark]

Q5)

State three inspection checks that may be carried out on an armoured cable installation using the sense of touch?

Any answers?

​

SWA adequately supported so as to avoid any mechanical stress.
Steel wires secured into gland and effectively connected to earth.
Glands tightened correctly
Shroud fitted over gland correctly
Connection of conductors​

 

[kennydeeee]

Cable not overheating feel
Temperure with hand

Check glands are secure shake with hand

Ensure Terminations are tight using suitable screwdriver

 

[IQ Electrical]

Originally Posted by abingdonjon
Q5)

State three inspection checks that may be carried out on an armoured cable installation using the sense of touch?

Any answers?

Q11)
State the effect on measured values of insulation resisLance of a230 V circuit if an​

insulation resistance test is carried out

i) between live conductors to earth with a tungsten lamp in circuit

ii)between live conductors with a switched fused connection unit, having a
neon indicator. left in the off position.

Any answers?

i) The instrument would display a dead short, reading through the filament.
ii) In the off position it would not effect the reading.

Is that exactly how the question was written in i?

'Between live conductors to earth' could mean between L+N joined together to earth in which case the lamp would have no effect.

Not that I'm in any way suggesting ambiguity in a City & Guilds question!

 

[kennydeeee]

That's the way I read the question put down no effect for the first part put down 500v dc for the second part then went back and change it to 250v dc and record as a limitation if the lamp cannot be removed think I lost a mark for this 1

 

[sparks_114]

Originally Posted by abingdonjon
Q5)

State three inspection checks that may be carried out on an armoured cable installation using the sense of touch?

Any answers?

Q11)
State the effect on measured values of insulation resisLance of a230 V circuit if an​

insulation resistance test is carried out

i) between live conductors to earth with a tungsten lamp in circuit

ii)between live conductors with a switched fused connection unit, having a
neon indicator. left in the off position.

Any answers?




Is that exactly how the question was written in i?

'Between live conductors to earth' could mean between L+N joined together to earth in which case the lamp would have no effect.

Not that I'm in any way suggesting ambiguity in a City & Guilds question!

Yes, I nearly got caught out on that one and only noticed it when I was checking my answers over and managed to change it thence. It should have no affect as the test is to earth.

 

[kennydeeee]

That's the way I read the question put down no effect for the first part put down 500v dc for the second part then went back and change it to 250v dc and record as a limitation if the lamp cannot be removed think I lost a mark for this 1

 

[Richard]

It just says state the effect....So if the neon is out of circuit, then no effect.....surely!!

 

[abingdonjon]

Totally screwed up on that question then. It's so obvious when answers are in front of you, and you draw a complete blank at the time! I stated it would record an inaccurate reading for first answer, 2nd answer stated the entire length of the circuit will not be tested.....duurgh! live and learn I guess!

 

[kennydeeee]

Just marked mine up think I got in around 85%

 

[72-van]

85% wow

 

[kennydeeee]

Just hope it's enough with the floating pass mark

 

[72-van]

Well if your just hoping for a pass with more than 85% i aint got no chance at all

I was feeling quite content with myself when i got a few questions i knew the answer to .Shame i had so many bad guesses..maybe next time

72-van

 

[kennydeeee]

Chin up mate I'm sure you will do fine