PFC & Earth Loop Imp Tests.

[OldskoolUpNorth]

Alreet all,

Went for an interview for a FM company recently and got asked a couple of, what I thought were, ambiguous questions.

Thought i'd find out what everyone else thinks.

1) What would you expect to find during PFC test?

&

2)What would you expect to find during Earth Loop Imp test.

Answers on a postcard.........


Neil.

 

[Former Sponsor TM]

Possibly the following:

1) A result in kA that determines the fault current likely to flow in the event of a fault. The lower the external impedance of a supply, the greater the fault current would likely to be. I'd also explain to make a note to check whether the MCB's/RCBO's and switchgear within an installation are likely to be rated to the prospective fault current.

2) A result in ohms, which complies with the relevant earth system value, TT, TNC-S, TNS etc. The Zs result that you obtained may also need investigating if it is greater than your Ze test and your R1+R2 test results combined.

Any comments welcome!!

 

[OldskoolUpNorth]

Thanks Test-Meter,

Answers,

1) No more than 16kA except in parts of London
2) Max 1 Ohm

Now call me crazy but that doesn't sound to me like the question they were asking.

I thought they were after an explaination of the relevance and not a max value.

I got No1 right but went into the details of Ze with No2.

Why can't they say what they're looking for rather than being vague... Jeez!

 

[telectrix]

2) Max 1 Ohm

if they've ever worked on a TT system, they're dreaming, unless the rod/s were installed by eng54. LOL.

 

[somersetsparks]

Thanks Test-Meter,

Answers,

1) No more than 16kA except in parts of London
2) Max 1 Ohm

Now call me crazy but that doesn't sound to me like the question they were asking.

I thought they were after an explaination of the relevance and not a max value.

I got No1 right but went into the details of Ze with No2.

Why can't they say what they're looking for rather than being vague... Jeez!

Well, 1 Ohm is the maximum for which system? Its 0.8 for TNS and 200+ For TT, this was a pretty poor question.

 

[OldskoolUpNorth]

Can you see my confusion?

I was on about a range of values dependant upon blah blah blah...

and the answer I got

'Your over thinking it'

No specific system mentioned, no details whatsoever, just the question.

 

[telectrix]

typical suits. read a few bits and think they know it all.

 

[somersetsparks]

Can you see my confusion?

I was on about a range of values dependant upon blah blah blah...

and the answer I got

'Your over thinking it'

No specific system mentioned, no details whatsoever, just the question.

Thats a rubbish question probably taken straight from a city and guilds paper, they seem to be the main crap question purveyors!

 

[telectrix]

typical suits. read a few bits and think they know it all.

my answers would have been.1. expect my 1552 to show a PFC reading. 2. expect it to show a Ze value.

 

[OldskoolUpNorth]

telectrix..

that would of been a top answer.. ha ha.

Somerset,

they do tend to go the C&G 'can you guess what we mean' question!

 

[somersetsparks]

telectrix..

that would of been a top answer.. ha ha.

Somerset,

they do tend to go the C&G 'can you guess what we mean' question!

Yet I doubt they listed clairvoyancy as one of the 'essential skills' that they needed from their applicants, bl*ody companies!

 

[Sparky Ninja]

I'm very familiar with C&G's type questioning, and even they wouldn't try some imaginary nonsense like that.

I'd have offered him some educating.


I've seen things like this before myself. I once went for an interview at a company in Leather head and the interviewee wrote down three formulas, each with a symbol missing and he asked me to find them. The answer to all three was 'I' and I think maybe I intimidated him from asking any more..

I got the job, but I wasn't interested any more.

 

[Farmelectrics]

did you get the job

 

[Sparky Ninja]

did you get the job

good question...

 

[Farmelectrics]

old skool on edge here did you get the job lol