An Awful Feeling This

[gap30]

Which of the below instruments need leads compliant with GS38.

1. Earth fault loop impedance tester.
2. continuity tester. in 2391 land this does not exist
3. insulation resistance tester.
4 Approved voltage indicator.

:hat:

low-resistance test leads do not need to be compliant with gs38, insulation resistance tester does and all other 'live' tests/testers

finger guards
fused leads
4mm tip but pref 2mm

 

[Sparky Ninja]

this little sh*t has been bugging me for days

List, in the correct sequence, the first three tests to be carried out on a newly installed lighting circuit.

continuity of protective conductors
insulation resistance
polarity or earth loop impedance (Zs)

i have been speaking to a couple of very experienced lads about this today and even they were not sure i would be more likely to believe its

continuity of protective conductors
insulation resistance
earth loop impedance

you are fine with polarity.

the trick in the question which catches people out is the absence of the continuity of ring, which you've correctly identified already.

 

[gap30]

you are fine with polarity.

the trick in the question which catches people out is the absence of the continuity of ring, which you've correctly identified already.

so as to any 'radial' circuit it would always be polarity

first 3 test in general

cont prot cond
cont ring final cond
ins resistance

 

[JUD]

this little sh*t has been bugging me for days

List, in the correct sequence, the first three tests to be carried out on a newly installed lighting circuit.

continuity of protective conductors
insulation resistance
polarity or earth loop impedance (Zs)

i have been speaking to a couple of very experienced lads about this today and even they were not sure i would be more likely to believe its

continuity of protective conductors
insulation resistance
earth loop impedance

CRIPLE PF

Continuity of protective conductors including main and supplementary equipotential bonding -- Dead test
Ring final circuit continuity -- Dead test
Insulation Resistance -- Dead test
Polarity (This can be done at the same time as cpc continuity) -- Dead test
Live Polarity (Polarity of Supply) -- Live test
Earth Loop Impedance -- Live test

Prospective Fault Current -- Live test
F​unctional Tests -- Live test

I think that's right :biggrin5:

The full sequence of tests is on page 33 of GN3

 

[brucelee]

see part 7 regs they in there

yes for fire risks eg where combustible material hay stores flour stores, wood working facilities any fire risk
for tt other than socket outlets ie sub main and other circuits not moren than 300mA
exhibitions shows and stands eg
a cable intended to supply temporary structures 300mA rcd or s type if discrimination with rcds protecting final circuits
temporary electrical installations for structures ,amusment devices and booths at fairgrounds
amusemnet parks and circuses

 

[malcolmsanford]

so as to any 'radial' circuit it would always be polarity

first 3 test in general

cont prot cond
cont ring final cond
ins resistance

How can a Radial circuit have the ring final continuity test?

For a radial it would be as your lighting circuit, which are radials circuits as well

Continuity of protective conductors
Insulation resistance
Polarity.

 

[La Poste]

State three examples where you might need Supplementary bonding.

1. In a earth free installation
2. In a bathroom where circuits are not protected by an 30ma RCD.
3. In a circuit where the required disconnection times can not be met.

 

[johnboy6083]

State three examples where you might need Supplementary bonding.

1. In a earth free installation
2. In a bathroom where circuits are not protected by an 30ma RCD.
3. In a circuit where the required disconnection times can not be met.

it is a last resort option to lower Zs,if the circuit will not otherwise comply.

 

[La Poste]

Conductive locations with restrictive movement.

 

[IQ Electrical]

State three examples where you might need Supplementary bonding.

1. In a earth free installation
2. In a bathroom where circuits are not protected by an 30ma RCD.
3. In a circuit where the required disconnection times can not be met.

Don't forget that even with RCD protection, all extraneous-conductive parts of the location must still be 'effectively connected to the protective equipotential bonding' in accordance with 411.3.1.2

 

[La Poste]

Oh yeah in a milking parlour on an agricultural installation, to stop the cows getting a tingle.
Nearly forgot that one.
:alucard:

Some definitions.
1. main protective bonding conductor.
2. supplementary protective bonding conductor.
The reason for them is provide equipotential bonding

Are those the right terms to use?

 

[gap30]

Stick that in your pipe Spin!

514.9.1 a legible diagram, chart or table or equivalent form of information shall be provided indicated in particular:

the type and composition of each circuit
the method used for compliance with regs 410.3.2
the information necessary for the identification of each device performing the functions of protection, isolation and switching and its location
any circuit and equipment vulnerable to a typical test

a copy place within or adjacent to each db

page 93 of the regs

has anybody got a copy of one of these sheets

i see them all the time but never really took any notice of them

 

[brucelee]

mate only place i seen them when you buy ccus sometimes they in there

 

[gap30]

explain why it is necessary to determine the earth fault loop impedance value of a circuit (3 marks)

i aint going to lie i am guessing this one - i could look in the books right in front of me now but i would rather make a fool of myself lol

to verify if a fault current occurs in the circuit there is an effective fault path or something like that - brucelee or the REGS ON LEGS or someone will put me right

 

[IQ Electrical]

explain why it is necessary to determine the earth fault loop impedance value of a circuit (3 marks)

i aint going to lie i am guessing this one - i could look in the books right in front of me now but i would rather make a fool of myself lol

to verify if a fault current occurs in the circuit there is an effective fault path or something like that - brucelee or the REGS ON LEGS or someone will put me right

To determine that the value is low enough to allow operation of the overcurrent protective device within the time specified.