Fluke 1652b tester new to electrics learning to test help appreciated

[Dews84]

Hi all help is appreciated
I'm trying to figure out what I am doing wrong

Fluke tester domestic single phase Tncs system
ze test..circuits and main switch open circuit....hi current loop setting on tester......crop clip main earth once removed from busbar... Line to line on supply(live side incoming) of consumer unit neutral lead to (neutral side incoming) press test gives ze reading say .26. Also gives pefc of 910amps.
now from what I under stand I must reconnect main earth and put croc clip on earth bulbar to obtain the true pefc so I do this press test give reding. Now from reading the manual of tester says to press f1 to toggle from l-pe to l-n not moving any of the leads from there position of pefc test to get the pssc result obviously needing to press test again, but here is the problem as the tester makes a buzzing sound and gives no reading clearly it doesn't like it. I have therefore tried this test t. Friends house on another tncs system. Please help this is really annoying me is it because it will only give me a pefc dude to the neutral and earth being one as a tncs system?
If u can help please do and also describe to me the testing sequence for three phases system with this tester

 

[SirKit Breaker]

Hello mate,

As you are new to testing and have an excellent piece of kit to test with, do these two things first, and i am not trying to belittle you. Have a good read through the test instrument instruction manual and CD. Buy yourself IET Guidance note 3, and spend a bit of time studying it.

How to do a Ze test:

Isolate the installation (switch off the main switch)
Disconnect the main earthing terminal from the dist board.
Connect red lead to live on supply side of main switch
Connect black lead to Neutral on supply side of main switch
Connect green lead to the earthing cable that you have disconnected
Set tester to correct range and press test.
You will get the Ze value displayed, and it will also give you PEFC, it wont display PSSC because you are on single phase, and you havent got 2 phases to to give you PSSC.

Unless the tester is suitable for measuring PSSC between phases you shouldnt do it, it is very dangerous.

Three phase method is exactly the same, but do the same test 3 times, once on each phase, then double the highest of the 3 PEFC readings to give you PSSC.

GN3 explains it very well, and it is illustrated.

Cheers...........Howard

 

[Sharpend]

On single phase toggle f1 to l-n disconnect earth lead leaving live and neutral connected hit test button. Should give you a reading. (The earth can remain connected if you wish, shouldn't make any difference) if the tester is warbling at you then it is generally a live that is not connected, if it comes up with >2000 then it's a neutral not connected.

 

[Richard Burns]

If you are testing L-N to get your PSCC then is it not a 2 wire test i.e. no green wire connected to earth?

 

[Sharpend]

Correct, however the earth plays no part so can be left connected.

 

[biggsy]

This is live test have you got the lviltage symbol on screen like lighting flash f1just toggles leade

 

[Dews84]

Thanks for all replies although confusing as ppl seem to have altering opinions.
i have gn3 amendment one just arrived today as well as Chris kitcher third edition of inspection testing and certification on it way.
So can we all be in agreement that pscc is not a test that can be done on single phase installations such as domestics property's 1 phases 2 pole for example.
yes I agree that f1 just toggles between l-pe to l-n and the manual states that no leads need disconnecting.to be fair I have only seen psCC done on a three phase board. So just to clarify three phase board ze would be

L1-n-e
L2-n-e
L3-n-e highest recorded for ze

Reconnect main earth
f1 toggle to l-pe
L1-n-e
L2-n-e
L3-n-e highest is the pefc

F1 toggle to l-n

L1-n-e
L2-n-e
L3-n-e highest is the pscc

Pscc / pefc highest equals pfc x2 for three phase

Thanks again reading is okay but then you can be second guessing yourself on hand tutors theres no alternative

 

[Richard Burns]

I am slightly surprised by Sirkit breakers response since PSCC is a very common test and is applicable to both single and three phase. PSCC is the prospective short circuit current either between a phase and neutral for single phase or, for three phase only, between phases. The PEFC value is the same for single or three phase and is not doubled.

However I would await Howards response as I would normally expect him to be correct.

If your tester can only test between phase and neutral then the rule of thumb is that the phase to phase current will be twice the phase to neutral current.

From your post above:

L1-n-e
L2-n-e
L3-n-e highest recorded for ze Correct

Reconnect main earth
f1 toggle to l-pe
L1-n-e
L2-n-e
L3-n-e highest is the pefc Correct

F1 toggle to l-n

L1-n-e
L2-n-e
L3-n-e highest is the pscc Highest x 2 is the PSCC

Pscc / pefc highest equals pfc x2 for three phase PEFC is not multiplied by two, only the L-N PSCC is multiplied by two (to give the approx phase to phase PSCC).
Your overall PFC will then be PSCC (twice the L-N fault current) as this will always be higher than PEFC for three phase.

 

[SirKit Breaker]

Sorry mate it was late and id had a few, a grey moment!!!

 

[telectrix]

could it be the fact that as it's TNC-S, you are performing the same test twice (as N and E are connected together at the cut-out) so the fluke doesn't like it.

 

[Jay Sparks]

Sorry mate it was late and id had a few, a grey moment!!!

I have these alot, but with me its a blonde moment and doesnt always include drink!!lol

 

[Dews84]

Well thanks again ppl. Yes I thought this could be the case as a tncs supply but mr burns says can only do pscc on three phase board. Which does sound correct although I don't know why as basically the test I've been doing on signal phase board for pscc is tester on hi current press f1 toggle to get l-n ...leads are already on line and neutral (earth on bus bar but not been used for this test) and as said before won't give a reading now if this was three phases I'd have my leads on the same connects and be doing one phase at a time therefore why would it give me a reading to not give me a reading on a domestic supply after all when doing three phase I'm measuring one phase at a time to neutral... I don't mean to challenge what you say I'm just a little lost mr burns if you could explain be helpful.
Also someone mentioned phase to phase testing how is this done and does my tester allow me to do this safely thanks again

 

[DJ Ovengloves]

OP, I mean this in a nice constructive way for you to think about, but is it possible to have a short circuit in a 1 phase board and how (if it was possible to do so ) would you measure and calculate it!

Well thanks again ppl. Yes I thought this could be the case as a tncs supply but mr burns says can only do pscc on three phase board. Which does sound correct although I don't know why as basically the test I've been doing on signal phase board for pscc is tester on hi current press f1 toggle to get l-n ...leads are already on line and neutral (earth on bus bar but not been used for this test) and as said before won't give a reading now if this was three phases I'd have my leads on the same connects and be doing one phase at a time therefore why would it give me a reading to not give me a reading on a domestic supply after all when doing three phase I'm measuring one phase at a time to neutral... I don't mean to challenge what you say I'm just a little lost mr burns if you could explain be helpful.
Also someone mentioned phase to phase testing how is this done and does my tester allow me to do this safely thanks again

 

[Richard Burns]

Well thanks again ppl. Yes I thought this could be the case as a tncs supply but mr burns says can only do pscc on three phase board. Which does sound correct although I don't know why as basically the test I've been doing on signal phase board for pscc is tester on hi current press f1 toggle to get l-n ...leads are already on line and neutral (earth on bus bar but not been used for this test) and as said before won't give a reading now if this was three phases I'd have my leads on the same connects and be doing one phase at a time therefore why would it give me a reading to not give me a reading on a domestic supply after all when doing three phase I'm measuring one phase at a time to neutral... I don't mean to challenge what you say I'm just a little lost mr burns if you could explain be helpful.
Also someone mentioned phase to phase testing how is this done and does my tester allow me to do this safely thanks again

I have not said that PSCC can only be done on three phase.
PSCC can be done on both single and three phase.

You will need to read the instruction manual to check if your tester can do phase to phase short circuit testing (I think it can but you MUST check first). The tester must be able to manage the voltage and current and will really not like it and can produce dangerous voltages / fry itself if it cannot do this test.
If it can do this test then it is the three tests L1-L2, L1-L3, L2-L3. This will give you your measured PSCC directly (and this will also be your PFC).

From your description I cannot tell why the tester is not giving a reading, are there any warning triangles or error messages showing up when you try the test that may indicate why it does not work?