AM2 fault finding help

[Bradley6969]

Hi don’t do that much fault finding and could do with some help, AM2 7 faults to find using on a continuity tester so can only be one of four things, but not really sure what readings to expect?
Short circuit = tester should show a few ohms but may have some resistance in leads and bleep
Open circuit = tester will show 0L and won’t bleep
High resistance = by high reading
Crossed polarity = cross over connections?
Anyone know a best way to do these as have a clue but not sure is it just the same as dead testing as you would normally

 

[Toneyz]

Have you/going to be taught this on the course ?.

 

[The Ghost]

Bradley your profile says you have no qualifications, how is it you are considering AM2? Sounds like you are trying to run before you can walk.

 

[Richard Burns]

The resistance values you measure will be similar in magnitude to those you see when you are testing an installation.
A direct connection along a cable will tend to be in the 0.00 to 2.00 Ω ragne depending on length of cable.
A non connected cable will show an effective infinite resistance, or OL, or >2000Ω or such like i.e the maximum the meter can read.
High resistance values on a continuity tester would be in the hundreds of ohms to over limit ranges.
Crossed connections will show over limit values instead of low resistance if you are measuring from one point of connection to a remote point of connection, say from CU to end of circuit and testing the line terminals then you would expect a very low result for the length of cable but instead would get a non connected reading.

 

[Bradley6969]

Have you/going to be taught this on the course ?.

3rd year apprentice got AM2 in few weeks

 

[Bradley6969]

Bradley your profile says you have no qualifications, how is it you are considering AM2? Sounds like you are trying to run before you can walk.

I’m 3rd year apprentice have AM2 in few weeks but have little knowledge fault finding

 

[Bradley6969]

The resistance values you measure will be similar in magnitude to those you see when you are testing an installation.
A direct connection along a cable will tend to be in the 0.00 to 2.00 Ω ragne depending on length of cable.
A non connected cable will show an effective infinite resistance, or OL, or >2000Ω or such like i.e the maximum the meter can read.
High resistance values on a continuity tester would be in the hundreds of ohms to over limit ranges.
Crossed connections will show over limit values instead of low resistance if you are measuring from one point of connection to a remote point of connection, say from CU to end of circuit and testing the line terminals then you would expect a very low result for the length of cable but instead would get a non connected reading.

Ok thanks I understand a bit more, will these tests basically just be how you would dead test normally? Eg for ring main do end to ends and R1+R2, I just get confused as your only allowed a continuity tester and they’ve all got to be a wiring fault

 

[Richard Burns]

Just a diagram of some possible examples and likely readings, this is shown on a socket circuit but could be any circuit. This is probably more complex than required for AM2 that will usually just be point to point testing.

e.g is there line continuity through the switch, no, so the switch is either off, faulty or has a loose connection.
Test for these possibilities: OK switched line connector has become disconnected on inspection of the switch.
So re connection of this conductor on a safely isolated circuit will resolve the problem:
Fault resolution: isolate circuit, reconnect conductor, test continuity is now normal and restore power.

 

[Bradley6969]

Just a diagram of some possible examples and likely readings, this is shown on a socket circuit but could be any circuit. This is probably more complex than required for AM2 that will usually just be point to point testing.
View attachment 38731
e.g is there line continuity through the switch, no, so the switch is either off, faulty or has a loose connection.
Test for these possibilities: OK switched line connector has become disconnected on inspection of the switch.
So re connection of this conductor on a safely isolated circuit will resolve the problem:
Fault resolution: isolate circuit, reconnect conductor, test continuity is now normal and restore power.

Thanks that’s helped a lot, my problem is I over think to much

 

[Strima]

Fault finding is done on a switched fault board, you will be given seven faults to identify, there is no need to rectify. All you need to give is type of fault, location and rectification method.

There are too many faults that you may be given to list here but the types of fault can be:

• Short circuit
• No continuity
• Polarity
• High resistance

Work through the faults, if you get stuck ask if you can come back to it later and crack on with the others. This should give you time to clear your head.

All the faults will be wiring faults so ignore the accessories.

Common failure points:

• Candidates do not correctly identify the faults
• Candidates do not record a correct method for rectifying the faults

 

[Bradley6969]

Fault finding is done on a switched fault board, you will be given seven faults to identify, there is no need to rectify. All you need to give is type of fault, location and rectification method.

There are too many faults that you may be given to list here but the types of fault can be:

• Short circuit
• No continuity
• Polarity
• High resistance

Work through the faults, if you get stuck ask if you can come back to it later and crack on with the others. This should give you time to clear your head.

All the faults will be wiring faults so ignore the accessories.

Common failure points:

• Candidates do not correctly identify the faults
• Candidates do not record a correct method for rectifying the faults

Thanks appreciate it, I just over complicate things too much but should be fine I’m all good with testing just gotta take my time and read faults thoroughly