high reading

[sparkies2306]

Hi guys,

Was doing a bit of testing on a new house today i was doing a test on mains on a tncs system or pme for short

the regs states reading can be a max 0.35 when i done the test i was gettinmg 0.41 have checked all supplies and earth to make sure of good connections but all is ok

would anyone have any sugestions on how to get this down the supply to house seems to be coming a fair distance to house as its out in the country would this have any bearing on it

any help appreciated

 

[Deleted member 26818]

Hi guys,

Was doing a bit of testing on a new house today i was doing a test on mains on a tncs system or pme for short

the regs states reading can be a max 0.35 when i done the test i was gettinmg 0.41 have checked all supplies and earth to make sure of good connections but all is ok

would anyone have any sugestions on how to get this down the supply to house seems to be coming a fair distance to house as its out in the country would this have any bearing on it

any help appreciated

Which Regs. state that the max reading is 0.35?
As far as I'm aware, guidlines suggest the max resistance should be 0.35, nothing states that it must be.
If you were to inform the DNO, that the reading is 0.41, they would probably take no action, and will inform you that the 0,35 is just a guidline.

 

[sparkies2306]

apologies spinlondon i did mean resistance i understand what your saying but just wanted to put it out there to see what others think to be honest i have never had as high a result on a pme job before so wanted to check with you guys
i ave an inspection next week with niceic and a very fussy inspector its something he will look at
cheers

 

[Deleted member 26818]

The high reading could be down to a poor PME connection somewhere on the network, or it could be just that the installation is a long way from the supply.
However, it could also be due to an incorrectly calibrated meter, or even poor connection of probes/terminals.
I would suggest that you report the situation to the DNO, but as I posted earlier, be prepared for them to fob you off.

 

[SirKit Breaker]

Make sure you have got really good connections with your leads, it is easy to drop a bit of resistance into the mix if your probes aren't pushed fully on to the leads etc. Been there, done it, and got the red face when YEDL eng came out for nothing! I wont elaborate except to say it had something to do with the aftermath of a night on the ale, and fused test leads........you can work out the rest for yourselves.

Cheers.........Howard

 

[mattmoo1974]

NULL your leads ^_^

 

[IQ Electrical]

It's impedance as it's a live test.

I'd be surprised if you can null leads on a Zs/Ze test, I've never seen a tester with this option.

 

[sparkies2306]

All leads were perfect and once i got the reading nulling my leads was the first thing i done. originally it was 0.43 went down to 0.41 using the fluke 1653b all in tester

and i think i agree with spinlondon the instalation is along way from the supply which is why i thought may be the high reading

thanks for help guys and advice

 

[sparkies2306]

Hi iq you can null the leads on a three lead tester they actually give you a 3 lead connection plate to do it with this is the fluke 1653b tester

 

[Guest123]

The 1653B asks you to null the laeds for EFLI when you first use it.

It even comes with a special adapter to allow you to do it.

 

[telectrix]

it's why they're called fluke, because it's a fluke if you get it right 1st time.

 

[IQ Electrical]

I've been a Megger man for so long now I forget other manufacturers exist, I live and learn!

 

[telectrix]

always had megger, starting with the wind up model, circa 1970. used to be called an apprentice alarm clock.