Please need some help

[lim15]

Hello

I am new to the forum but would like to ask you for some help.

I am doing my electrician course and for that course have to complete some assessments. There is few questions in witch i struggle, This is my third time when they ask me to correct some of the questions. I keep working on them but i have few with cant find answer, maybe somebody could help me a bit with them :

Anyway the questions are:

1.Does BS7671 define a plug and socket outlet as a means to secure isolation?

2. What senses do you use in fault finding.

3. Why would an induced over voltage occur and what damage may occur if this happened while working on an unprotected computer.

4. Provide two examples of user instructions?

5. Which regulation is concerned with the identification of protective conductors and which colours are required to be used?

6. An installation of six circuits have individual resistances of 5MΩ, 3.6MΩ , 8MΩ , 200MΩ , 200MΩ, and 200MΩ, what is the total resistance and is this value for the circuits satisfactory for a domestic installation

I may have some more latter but first i want to try find my self the answer.

I would really appreciate if anybody could help me with the questions above.

Thank you.

 

[M107]

Hello I am new to the forum but would like to ask you for some help.

I am doing my electrician course and for that course have to complete some assessments. There is few questions in witch i struggle, This is my third time when they ask me to correct some of the questions. I keep working on them but i have few with cant find answer, maybe somebody could help me a bit with them :

Anyway the questions are:

1.Does BS7671 define a plug and socket outlet as a means to secure isolation?

Look at table 53.2

2. What senses do you use in fault finding.

common (dont use only joking)

Sight

smell

touch

hearing

3. Why would an induced over voltage occur and what damage may occur if this happened while working on an unprotected computer.

A guess on my part...

Lightening strike & pc would be fried if unprtected by surge protection

4. Provide two examples of user instructions?

Verbal

manufacturer user manuals

5. Which regulation is concerned with the identification of protective conductors and which colours are required to be used? Look around 514

6. An installation of six circuits have individual resistances of 5MΩ, 3.6MΩ , 8MΩ , 200MΩ , 200MΩ, and 200MΩ, what is the total resistance and is this value for the circuits satisfactory for a domestic installation

Rt = 1/5 = 1/3.6 + 1/8 + 1/200 + 1/200 + 1/200=

0.2 + 0.28 + 0.125 + 0.005 + 0.005 + 0.005=

0.62=

1/0.62=

1.61 Mohms

Now look in the BRB to see if 1.61 Mohms is acceptable, or if not what action would you need to take...if any

I may have some more latter but first i want to try find my self the answer.

I would really appreciate if anybody could help me with the questions above.

Thank you.

My go for you, I've not given all answers as you do need to look in the BRB.

 

[lim15]

Thank you so much, This will do. You point me to the wright directions. Thank you!

 

[M107]

No problem, so long as you (or any others at college) put some effort in & dont just expect to get the straight answers you'll get all the help you need here.

 

[Manator]

So very true, a part of learning is to know where to look. If answers are given you will never learn this basic rule.

 

[Doc Hudson]

Hello Lim15, welcome to the forum, as Manator & M107 said this forum is very helpful and friendly to all levels of experience. But I would emphasis there is generally more respect and help from other members when an attempt has been made at answering a question first. Such as I have question 'xyz' I think the answer is 'abc' does this sound right? Rather than just 'can you do my homework answers for me'. No one gets ridiculed for asking a valid question.

Doc H.

 

[lim15]

Thank you for all replays. I don't mind to look for the answer is i know where to look for. An the help i got from here was very useful Thank you for that!

I have 3 more questions in with i need a help.

They are about drawings but i have no clue about it.

Unfortunately, I am no able to post them on a forum as i need to shown you the drawing plan with i cant attach to the post . If anybody have a time and like to have a look i can send the question by email with attach drawing.

I would appreciate any help on this.

Please send me PM with email if you interested.

Thank you.

 

[Doc Hudson]

You can use a link to an image you have saved to Photobucket, Flickr or a similar service etc..

http://photobucket.com/

http://www.flickr.com/

http://tinypic.com/

http://www.picturetrail.com/

http://www.theimagehosting.com/

Doc H.

 

[a1]

You could always attach them as an attachment to your post.. If you are struggling with a Photohosting account.

 

[lim15]

Ok with your advice i have open account with flicker. now I will post the questions

1. Using the drawing shown below you are required to complete a list of quantities for the installation as provided on the following pages.

http://www.flickr.com/photos/53587922@N03/4953485391/

List of Quantities

Location Circuit Rating Switches Points

1w 2w Int Pendant Batten Fitting

Dining

Kitchen

Breakfast

Garage

Hall

WC Down

Location Circuit Rating Sockets Spurs Control Sw

SW U/sw SW U/sw Cooker

Dining

Kitchen

Breakfast

Garage

Hall

WC Down

I hope this make sense.

Question 2

2. What extras have you identified from the drawing which do not fit on the list of quantities.

Question 3

3.What installation method accurately describes the wiring system shown in the picture.

http://www.flickr.com/photos/53587922@N03/4954093004

I hope all of this make sense to you?

 

[SPECIAL LOCATION]

Hello Lim welcome to the forum....

stuff the questions for one minute

have you found the virtual bar yet??

GuinnessGuinnessGuinnessGuinness

Thats better..... :^O

now then...

First of all question 3...

Installation methods... do you have a Regs book or On-Site Guide?

Installation methods start on page 261 in the big red book...

or

page 52 On site guide....

remember the on-site guide is predominantly a short summary of key bits relating to Domestic and light commercial (single phase stuff!)

Installation methods are things like...

Clipped direct on surface,

Embedded in masonry wall,

Buried in insulation,

Run in conduit or trunking,

Cable trays,

Grouped with other cables run single

etc..

etc..

if you look in the books they all have number codes..

so try and find the most suitable match for your second picture.

Q1

List Of Quantities....

You need to be thinking of all the physical bits you would need to buy and fix to the wall to get that installation working....

e.g.

Light switches (how may gang single double / One way or Two way etc.....)

Socket outlets, single double etc..

Cable size and length,

Cable clips fixings..

Screws plugs,

Sleeving,

Mounting boxes

etc..

etc..

I would approach it by looking at your first drawing and go through room by room

Question 2...???

I am guessing that may be to do with the stuff that is described as "If Required" on the drawing..

e.g. it says Alarm board 'If required'..

& a fused spur & phone link 'If required'

i.e.

You list of quantities is what you actually have got to get from the wholesalers..

But you don't want to go purchasing stock until you have confirmed if the "if required items" are actually needed...

HTH

 

[lim15]

Thank you for great help . You really help me guys. all this questions i answered correct, but, failed on two other questions.

And hope you can help me again

The two questions i failed are:

1. A Hewden RCD protected socket outlet is installed in a greenhouse that is always damp and quite humid. What wiring system should be used and what IP rating is required for the enclosure

2.You have been asked to provide a supply for a new Information Technology centre within an existing installation. What type of wiring system should be used and why are

 

[M107]

1. A Hewden RCD protected socket outlet is installed in a greenhouse that is always damp and quite humid. What wiring system should be used and what IP rating is required for the enclosure

pvc conduit & singles or micc. IP rated at.......well the table is in the regs but take a look here

http://www.tlc-direct.co.uk/Technical/DataSheets/IPNumbers.htm

What would you go for in a green house where water is a given ?

2.You have been asked to provide a supply for a new Information Technology centre within an existing installation. What type of wiring system should be used and why are