Some help needed please

[Macwillis]

im a 3rd year apprentice and need some help on a few questions:

State the procedure and equipment required to perform each of the following tests

a) insulation resistance for alarm cables

b) continuity of alarm cables

c) Safe isolation of a 230Vac supply


for b) i was thinking multi-metre set on resistance shorting all the cores together at one end and testing between each one. and then checking them again un-shorted to make sure i dont have any shorts i shouldnt have.
and c) was thinking metre set on voltage

test the supply at my IAP for 230v remove the fuse from my 3a unswitched fused spur and put the fuse in my pocket. test at IAP again making sure the supply is dead.



any help would be greatly appreciated

 

[Spark123]

a) Have a look for the required tests required for ELV cables, the required test voltage and maximum allowable insulation resistance.
b) You can do continuity like that, or you can do continuity using a wander lead.
c) Nope - think of the safe isolation procedure. A multimeter can be incorrectly set. Always use approved voltage testers. Always prove the tester before and after checking the isolation.
http://www.niceic.org.uk/inc/file-g...(sec).pdf&RURL=/en/contractor/section.asp||13

 

[RF Lighting]

Are you an apprentice electrician or an apprentice alarm installer?

 

[Macwillis]

im an apprentice alarm engineer.

 

[ban-all-sheds]

At what point in your training do you cover off the Wiring Regulations, and the Building Regulations, and get a qualification relevant to electrical installation work that will let you register with a Competent Person scheme?

 

[Macwillis]

in my 1st year i did electrical principles.

 

[ban-all-sheds]

Yes, but at what point in your training do you cover off the Wiring Regulations, and the Building Regulations, and get a qualification relevant to electrical installation work that will let you register with a Competent Person scheme?

I ask not because I'm sniffy, but because if you don't then you'll not be able to effectively work in the domestic field.

 

[Macwillis]

i havent covered that in my course.

im doing a NVQ3 In emergency and security alarm systems.

im only asking because its part of my course, its a question on a project im doing.

 

[ban-all-sheds]

i havent covered that in my course.

im doing a NVQ3 In emergency and security alarm systems.

Not good, really, that they can turn you out with an NVQ3 but not get you qualified to work in domestic dwellings...

im only asking because its part of my course, its a question on a project im doing.

If it's part of your course did they not teach you it?

State the procedure and equipment required to perform each of the following tests

a) insulation resistance for alarm cables

Insulation resistance tester, often called a Megger. Don't know enough about alarm devices to know what precautions you should take before zapping the cables..

b) continuity of alarm cables

Continuity tester - either bridge cables at the origin and test at each point or use wander leads.

c) Safe isolation of a 230Vac supply

Approved indicating device and proving unit.

Check that it works, check that the supply is live, isolate the supply, check it is no longer live, check that the indicating device still works.

Depending on the environment you may need to install a lock-out of some sort to prevent the circuit being re-energised without your knowledge.

 

[Macwillis]

thats what i thought for B and C

ovs. if its a spur next to the panel i dont really need to worry about somebody turning it on.

ill ask about A at college.

thanks

 

[ban-all-sheds]

if its a spur next to the panel i dont really need to worry about somebody turning it on.

Not even if you've installed temporary links and have gone walkabout with your continuity tester?

 

[Macwillis]

im only testing for continuity at the panel tho.

 

[ban-all-sheds]

Does that work?

 

[ban-all-sheds]

c) Safe isolation of a 230Vac supply

http://cgi.ebay.co.uk/Martindale-Sa...ryZ25411QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

 

[Macwillis]

if its a spur next to the panel i dont really need to worry about somebody turning it on.

Not even if you've installed temporary links and have gone walkabout with your continuity tester?

i wouldnt install temporary links anyway. if i needed to power up the IAP for any reason i would do so using 12V SLA's