An Awful Feeling This

[jerrybouncer]

Good luckwith your exam. Relax and you'll be fine!!

 

[gap30]

dont get too excited the next part of the question got me puzzled

State
i. a suitable observation to be recorded on the periodic report if the voltage drop fails to comply
ii. one action which could be taken to rectify the situation in i. above

i. circuit blah blah failed volt drop test code 2
ii. reduce length of circuit?

anyone?

 

[brucelee]

have i got this right, i know this has already been discussed somewhere but wanted to try it off the top of my head

sorry to be a pain in the butt

during the course of the inspection one of the single phase radial circuits supplying an item of fixed electrical equipment is to be checked for voltage drop compliance. The circuit has the following characteristics
load current = 45 amp
circuit length = 80 metres
live conductors = 10mm
a. using the information given in figure 1 determine whether the circuit meets the requirements for voltage drop. Show all calculations

80 x 1.83 x 2 x 1.2/1000 = 0.35136

v = ixr

vd = 45 x 0.35136 = 15.8 volts

230v circuit 5% = 11.5 volts

so circuit does not comply

is this correct?

Hi mate

use formulae number calculation
eg
R =m/ohm/m x 2 x mf x Lenght /1000
=1.83 x 2 x 1.2 x 80 /1000
=0.35136
= 0.35 rounded down
vd = I X R



good luck mate

 

[IQ Electrical]

1 I'd be looking at a code 3 depending on the stated manufacturers tolerances for the fixed load (525.1)

2 Go for increased conductor CSA.

 

[gap30]

just got back, long questions were a doddle, short ones i reckon i got about 5 wrong

State three conditions that must apply before the issue of a minor electrical installation works certificate 3 marks

could i feck answer that one

state the test to be carried out to ensure safety before testing the rcbo 2 marks

hummed and harred for 20 minutes this was the last question, i put Ze then scribbled it out and put PFC

anyways quite optimistic as the long questions were easy, earth fault path drawing for tn-s, resistance one, conduit and trunking inspection which i have studied to the hilt so i prob failed lol

 

[russty]

state the test to be carried out to ensure safety before testing the rcbo 2 marks

hummed and harred for 20 minutes this was the last question, i put Ze then scribbled it out and put PFC

I put functional test of intergral test button!!

 

[gap30]

I put functional test of intergral test button!!

what result did you get for the insulation resistance?

i got 2.11 megohms

 

[russty]

correct here aswell. Finished the exam with an hour to go, just went over everything again. Feel if i dont do this one i need shooting!

 

[gap30]

correct here aswell. Finished the exam with an hour to go, just went over everything again. Feel if i dont do this one i need shooting!

ha ha know what you mean

 

[tony mc]

I would have a few days off now gap or you will go bonkers!!

After going over this post it looks like you have put in a lot of time and effort into your studies and have been encouraged by a lot of the forums members.

Fingers crossed and I do hope you have passed.

Regards

Tony

 

[pirhead]

Hi Mate
here are some things to help your remember stuff

Periodic inspection you are looking for a SADCOW. issues of Safety. Ageing, Deterioration. Corrosion, Overloading, Wear and Tear.

Also Insulation resistance is like a teabag the longer the cable the more perferations so more area to leak out of hence Insulation resistance decreases with length.

Cable resistance is like linking sausages togethr the longer the length the more sausages you have so greater resistance

Also learn the proper terminology for protective conductors. See little map at end of appdx 2
Circuit protective conductors connect to exposed conductive parts to MET. Exposed parts of electrical equpt motors lights etc

Main protective bonding connects gas and water Extraneoues conductive parts to MET. Any EXTRA METAL is Extraneous



Earthing conductor connected between MET and earth electrode

Hope this helps

 

[pirhead]

I think the answer shoud Zs as this verifies the presence of a circuit protective conductor in the first place. No cpc no effective operation

 

[IQ Electrical]

I think the answer shoud Zs as this verifies the presence of a circuit protective conductor in the first place. No cpc no effective operation

Correct, it's Zs, Guidance Note 3 2.7.18

 

[gap30]

all i had going round in my head was Zs but i thought that only applied to TT, with it being a TN-S i was looking at it for 20 mins, anyway now when i think about it i know Zs is the answer, actually during the exam i was pretty thorough and did not rush any questions but i just could not get the answers in my head to some of the questions

as i said i think i have dropped maybe five or six short questions

 

[brucelee]

dont worry Gap mate I reckon you will have done enough easy to doubt the answer during the exam always zs before rcd or rcbo tests all about the test sequence

you know now easy to get confused in exam conditions your gut was telling ypu one thing your head the other go with first thought usually correct unless your certain its wrong 100%

You done it now
the wait begins and goes on and on and on but not forever lol

good luck mate hope ya passed for your effort you deserve it