Urgent - Earth Fault Loop Paths

[paul2k]

Good morning,

I'm wondering if someone could help with explaining EARTH FAULT LOOP PATHS in a competent way for TT, TN-S, TN-C-S systems. I can draw them on a diagram however find it difficult to explain things. I'm currently doing a HND in Electrical Engineering and unfortunately have poor materials to reference an explanation.

Your help would be greatly appreciated.

Regards,

Paul

 

[Plonker 3]

A drawing will be the best way to explain them.

Although you may need to explain the difference in each of the esrthing arrangements you have mentioned. Do you know this?

 

[telectrix]

here. have a read:

https://www.google.co.uk/search?q=e...0l5.8543j0j8&sourceid=chrome&es_sm=0&ie=UTF-8

 

[Pete999]

https://www.google.co.uk/search?q=e...-8&oe=utf-8&gws_rd=cr&ei=zATOVJmuJIrpaPiMgIAJ

 

[paul2k]

Yes the diagrams are not an issue, however I don't have good enough materials to explain the earth fault paths correctly, hence I'm finding it a little difficult. The diagrams are already provided as all we have to do is explain the path.

 

[Geordie Spark]

https://www.google.co.uk/search?q=e...PvZLsP_UvXwgtgF&ved=0CD0QsAQ&biw=1024&bih=646

 

[trev]

So why is this so urgent on a Sunday morning marra? Homework due in tomorrow?
You could always try the time honoured "my dog ate it sir" excuse.

 

[baldsparkies]

Can you not just explain the various methods employed by which the earth fault current returns to the transformers centre point.
How that's achieved, along with the different resistance values and means of disconnection within the prescribed times.
You know the theory behind (DNO values of) TNC-S (PME) @ 0.35, TN-S @ 0.8, or TT @ 21.
Just take it from there and put pen to paper.

 

[Deleted member 26818]

I would probably start my description with a description of the current path in a normal circuit.
Gen set/transformer to current using device in installation, then return path via the neutral conductor to the star point at the Gen set/transformer.
I would then explain that in the event of a line to earth fault, the return path uses the means of earthing instead of, or as well as the neutral return path.
I would then go on to explain that with TT installations, the mass of the earth is used as part of the earth fault path, with TN-S, a separate earth conductor is used, and with TN-C and TN-C-S, the neutral conductor is used.

 

[baldsparkies]

Feels like your in a school playground first thing Monday morning.
Your mate hasn't done his homework and your frantically helping him to get it all written down before the teach asks for it.
Alternative is bend over lad, and a cane across yer backside.
Oops, they don't do that anymore !!
Just showed my age. :icon12:

 

[Geordie Spark]

Feels like your in a school playground first thing Monday morning.
Your mate hasn't done his homework and your frantically helping him to get it all written down before the teach asks for it.
Alternative is bend over lad, and a cane across yer backside.
Oops, they don't do that anymore !!
Just showed my age. :icon12:

Me too.

I remember it wasn't just the cane- it was the gym slipper, strap and blackboard ruler. In fact almost anything that came to hand, but no matter what it was it bloody hurt!!

Happy days!!