help practical exam tomorrow :-(

[iancornwall]

hi i am new here and am after some help please please. am going though my books as i have just found out my my level 2 practical exam tomorrow witch i thought i had a couple weeks untill got to do it. and and am having a problem. . i havent had much to do with testing and think im going to fail on the testing side. as due to family comitments i have been been able to attend limit practical lessons. i passed my my both level theorys with flying colours so am not a complete dumb ---. would just be very help full in what testing i have to do. i know i have to do a new installation and test. (dont beleve any fault findings) will i need to do cable calcs during the test to show how i have decided what cables to use?
i also beleve i will have to do a test on 3 phase to test voltage and amp pull.

what tests will i have to do and has any one got a quick noobie guide for the installation test and the 3 phase voltage and amp pull test please. i cant seem to find anything on the 3 phase. any help would be great as am pulling my ears out right now :-( practical work i am find its just testing as havent really done it before. really scared am going to fail.

 

[devon1]

I'm not sure what they do on the level 2 exam, but the 3 phase test maybe just to check with an approved voltage tester each phase to earth (230 volts), each phase to neutral (230 volts), then between each phase (400 volts). Make sure before the test you check the approved voltage tester on a proving unit. You should pass if you thoroughly read through your course material, i'm sure you'll be ok.

 

[Phil]

if it`s the l2 prac you should only really have to do a cont test and a ir test. don`t stress too much mate

 

[iancornwall]

thanks for the replys guys, i got the single phase starting to set in my head now just gotta try n rember witch ones to use for each test.

does anyone if i would need to know cable calcs of the top of my head for it? if so guess would need to refresh myself on mcb selection to. kinda things just do with out the maths when at work.

 

[pushrod]

Is it C&G level 2?

I remember we had a simple 3 phase test where we were just measuring the current in each phase with a 100 watt bulb connected firstly in each phase - we took current readings - all the same and then were asked what the current would be in the neutral - answer = zero, because it was a balanced load..

Then we were asked to to take readings with a 40W, 60W and 100W bulb in each phase ( remember I = P ÷ V, so you should be able to predict the approx value you get) and asked to predict what would we find in the neutral - answer = a current this time because the loads are unbalanced.

just remember that you connect the ammeter in series.

 

[Adam W]

I seem to remember doing the voltage testing on a different day to the AM1. You basically just have to put a clamp meter around some wires and write down the result, then explain that the
line voltage = phase voltage x √3.
Phase voltage will be around 110v, line voltage around 230.
In the AM1 I think you just have to test R1 + R2 and IR, you don't need any cable calcs but you will need to do safe isolation.
For R1 + R2 connect the cpc and line together in the cu and test between them both at the furthest points of the circuits (do both sides of the strappers on the lighting circuit) and write down the highest result.
For IR there is no sensitive equipment so you can just clip the leads on the busbar and earth bar and push the button, then move the clip from the earth bar to the neutral bar and do it again. (Again, remember to do both sides of the strappers).

You've got 2 days to do it all, which should be plenty of time.

 

[iancornwall]

thanks peps for the help, i going in today. will let you know how i get on.

 

[iancornwall]

well got on fine today got my installation all done and first half of the papper work. just gotta go back and do the tests and finish paper. im a lil confused thou. i think i now understand the 3 phase test after reading the paper, looks like the are gonna make it a unbalanced load and just gotta show that the current is returning back down the n and explain why. but the single phase i think they have worded it wrong.
in the results table i have to fill out, it asks for "continuity of protective devices(ohms) i guess they mean r2 or r1+r2 for this?
and then " insulation resistance (megohms) " but that is all it asks for not live to live and live to neutral. so am just a lil confused on what they are atually wanting. its only giving me one box per curcit for this ie the coninuty isnt broken down into 2 boxs and the same for resistance. any one know what they atually want? thanks