what do you make of this???

[Apache]

That's useful to know Applaud Smiley. With that in mind, when's the best time to change the batteries then? What should I use as a guide on the Fluke 1652 when doing a battery test?

14.00-14.10 or 23.20-23.35

:coat

 

[steptoe]

Im really getting confused now,

this started out as a 4mm radial SWA,

its now turned into a 2.5mmT&E ring final circuit.

??? ??? ??? ??? ??? ???

 

[steptoe]

OH, and remember to ZERO your leads, even on the Zs test.!!!

 

[SPECIAL LOCATION]

Funny you should mention that! I changed them today. Should I go over the tests again?

If you tested it on your calcard... old or new batteries...

and the readings were within tolerance then meters OK.

 

[SPECIAL LOCATION]

I've only had the tester since last June. Thought I was getting some funny readings last year, so returned it to manufacturer who said it was fine. Bought the Calcard and only tested it over the weekend - all results were within tolerances.

Sounds like your meters all right to me?

CalcardApplaud SmileyApplaud SmileyApplaud Smiley

good move!Guiness Drink

Have you got a spare full or near full drum of cable..

you can do another quick test on known good cable just to verify your meter..

You could also open up a few sockets and break the circuit down into two or three smaller sections make it easy to identify where the dodgy bit is? :|

*****WARNING*****

this sort of problem sounds like the classic situation when you can end up driving yourself round in circles doubting your own common sense.

Keep it back to basics..

have a notepad & pen handy to write down test results and the point on the circuit where you have tested, as you do them.

Remember:- 2.5mm C.S.A.

1m of 2.5mm will have 0.00741ohm per meter

so 10m of 2.5mm will be 0.074ohm

and 50m of 2.5mm will be 0.37ohm.

1.5mm C.S.A.

1m of 1.5mm will have 0.0121ohm per meter

so 10m of 1.5mm will be 0.121ohm

and 50m of 1.5mm will be 0.605ohm.

i.e use table 9a pg 166 On Site Guide to check your values relative to the actual real world cable lengths at your job.

AND...

don't beat yourself up thinking your hopeless...

all good sparks at various times go though the old "head scratching this don't make sense job"!

 

[avinalarf]

Im really getting confused now,this started out as a 4mm radial SWA,

its now turned into a 2.5mmT&E ring final circuit.

??? ??? ??? ??? ??? ???

Apologies again - the OP was regarding the R1+R2 differences which is on a 4mm SWA radial.

I then snuck in with another query regarding IR differences on a ring main within the same installation (thought it was wired in 2.5/1.5) but as AndyC has pointed out, cpc could be 1mm - shall check that again.

 

[ianmacd]

as AndyC has pointed out, cpc could be 1mm

:_|

 

[avinalarf]

I'm back!!!

The meter tails on this CU change need to be 25mm as they're only 16mm. The Siemens guy said that the earthing would have to be changed to, even though it's 10mm.

Can someone confirm this, as i've checked the OSG (pg 29) and it says that for TT, the cable can be as small as 4mm (unprotected) if it's not buried.

 

[Apache]

I'm back!!!The meter tails on this CU change need to be 25mm as they're only 16mm. The Siemens guy said that the earthing would have to be changed to, even though it's 10mm.

Can someone confirm this, as i've checked the OSG (pg 29) and it says that for TT, the cable can be as small as 4mm (unprotected) if it's not buried.

Nat

I asked about size of earth's in this thread and post 10 Batty says the DNO want 16mm. You got to give them what they wants.......

 

[avinalarf]

Thanks Apache

The earthing (on TT) is the consumer's responsibility so how can the DNO give the orders on cable size then?

 

[a1]

Thanks ApacheThe earthing (on TT) is the consumer's responsibility so how can the DNO give the orders on cable size then?

That's the way it is - You don't give them what they want and they'll refuse to connect.

 

[Andy™]

the regs do state smaller than 16 is enough, but some DNO staff seem to think 16 is needed. looks like you got an idiot there who doesnt know a thing about ohms law and the fact you will never get enough current flowing for 16mm to be needed (unless you stake their lead sheathed cable!)

 

[avinalarf]

Thanks for that AndyC. I thought that as well, but didn't want to get on my high horse as I'm not that experienced!!!

 

[steptoe]

hes prob being a nob cos your a gurl.

 

[avinalarf]

hes prob being a nob cos your a gurl.

:^O yeah! Fortunately [for him] I wasn't there and am just going by what the neighbours have told me. Spent nearly an hour speaking to various other nobs at EDF?Siements trying to find out who this engineer was and what EXACTLY was the problem...still waiting for them to get back to me.

 

[Andy™]

:^O yeah! Fortunately [for him] I wasn't there and am just going by what the neighbours have told me. Spent nearly an hour speaking to various other nobs at EDF?Siements trying to find out who this engineer was and what EXACTLY was the problem...still waiting for them to get back to me.

Be prepared for a long wait

 

[avinalarf]

Applaud Smiley - time for some :Y

 

[green-hornet]

Is there a dist board in the summer house?

Reason I ask is that if the circuit is protected from the main db and then a rod is inserted the earth path is extended, by connection through the linked earth from the main db.

Effectivly giving you two seperate earth paths, which could give you the test results you mention.

More often the main earth is carried across various rods whilst still connected to the main db.

Disconnect the cables and use a wander lead to test end to end continuity, remove any links to any rods installed.

You could test the Za of the rods if you have a tester which is cabable of this to establish the effective continuity to earth.

I would expect a break or connection through the length of the circuit as opposed to the earth rod but all avenues should be checked.

 

[avinalarf]

Siemens engineer returned this afternoon. Told me he'd come to change installation to PME! I was told by call centre that he was only returning to check the current system to see if it was ok to change, so I hadn't done anything to prepare for him. His response to this was that most areas are ok to change to PME, so they don't usually have to check.

Anyway, he begrudgingly gave me some 25mm tails and said he'd wait whilst I connected at the CU, then he connected to the meter. He then asked me to do a loop test, which came out at 0.34ohms.

Anyway, my query is:

When I upgraded the CU, the system was TT and all my tests were right for a TT system. Am I now obliged to re-test, because it's PME???

Cheers

 

[ianmacd]

Have you finished all the work and completed testing? The only think that should change is Ze and Zs of each circuit.

Ian.