Another Confused Testing Begginer

[Plonky]

Hi all.

My questions are to do with the ZE/ZS tests. I have only ever done these tests in a classroom environment. We were asked to build small ring mains or lighting circuits on a wooden board, we would do all the required tests, R1-R2 ZE etc, then take them apart and build a different circuit. When we did the tests we only ever had one circuit connected to the CSU at a time. However in the the real world there is going to be several circuits on the CSU, ring main, lighting cooker etc.

I am going to do some electrical jobs in my house for my Part-P assesment. I am going to rewire the cooker and shower circuit. Iam also going to rewire the electrics in the garage including a new CSU with RCD. Finally I am going to rewire the central heating circuit.

Question 1

I understand that the ZS is a test if the whole system so can this test be done anywhere within the electrical installation, ie on a ring, lighting cicuit or wherever is most convienent?

Question 2

I have recently rewired my central heating circuit, new controller stats etc and was wondering if I can do the ZS tests on a nearby socket outlet?

Question 3

Also I understand that you need to unplug everything to do these tests. I assume this includes all hard wired appliances?

Question 4

The electrics in my house were kind of bodged by the previous owner and not every socket outlet is connected to the new CSU, some are still on the original rewirable fuses. If I do the ZE at the new consumer unit will I have to a second one inside the older style fuse box or will these cables be tested as they are all connected to one common source?

Thanks in advance

 

[sparkytim]

Hi

Yes it can be a bit different in the Real World..

Q1

No Ze (External Earth loop impedance) is the Test for the whole system done at the origin to prove you have an Earth connection and obtain a value.

These should have a Maximum value of 0.35 for TNCS and 0.8 ohm for TNS.

Zs is the value of Earth loop impedance obtained from the furthest point on EACH circuit.

If circuit shock protection ONLY relys on Fuses or MCBs then a Max value is given in the Regs to ensure disconnection within the max time allowed i.e. 0.4 secs for most circuits on a TN system.

Q2

The heating system Zs is measured at the Fused connection unit for it.

Q3

You do not need to unplug for Zs tests.

Q4

Zs tests do not Test cables they only verify the earth path

What level training have You achieved so far?

Further training may be required to satisfy "Part P" assessment

 

[ADS]

I don't think you should be allowed near a test meter and you certainly shouldn't be doing any of the work/testing that you describe - you're going to kill yourself or someone else. :red card

 

[Plonky]

Yeah thanks for that ADS. I suppose you were born with all your current wisdom

 

[ADS]

Yeah thanks for that ADS. I suppose you were born with all your current wisdom

No, but I knew not to run before I could walk

 

[ADS]

To be fair, if you really want to learn, have a good read of GN3 - read it a couple of times if you have to.

I was having a dig, but I'm deadly serious about attempting live tests when you don't know what you are doing.

 

[Nicky Tesla]

im going to take my driving test tomorrow so i just need to know a few things

1. wots the middle peddle for

2. do i need to stop or go at a red light, we did this in theory using toy cars but i cant remember

3. is the engine cover a bonnet or a bootWet Fish

 

[tom1]

To be fair, if you really want to learn, have a good read of GN3 - read it a couple of times if you have to.I was having a dig, but I'm deadly serious about attempting live tests when you don't know what you are doing.

on site guide runs through them and nic eic do a good book and dvd.

who did you train with?

 

[ADS]

Me?? - or the Op

 

[Plonky]

I did my training at 'Able Skills' in Dartford Kent

 

[tom1]

Me?? - or the Op

the op mate

 

[ADS]

the op mate

Sorry mate, just with you quoting me, then asking the question ha ha

 

[PC Electrics]

Guys, this just has to be a wind up, surely.

 

[a1spark]

Hi, Plonky mate . Listen the best advice I could give is to try and team up with an experienced Spark and improve as you go along. You are correct we did all have to learn at the outset but we took are time before jumping in. The overwhelming opinion is that you are not yet ready to carry out any serious Sparking on your own...beleive me mate your receiving good advice here tonight and it will save you comming a cropper. I hope you take the advice and Good Luck for the future !

a1 Spark

 

[Nicky Tesla]

Part P is a scheme for COMPETENT electricians not for those who ask those types of questions.

 

[kme]

I`m afraid I must agree with Nicky & ADS here mate - you really aren`t competent to undertake the works you describe above - no offence intended, but there IS a minimum standard of knowledge & competence expected, and your questions demonstrate a distinct lack of understanding of fundamentals.

Yes, we`re here to help; but we cannot (and indeed shouldn`t) be a "learning centre" where people come to learn rudimentary skills.

KME

 

[paul b b]

Plonkey,

i would get hold of the company you trained with and ask if you can go back down for a day to do some more testing, get a real good feel for it, you wont pass an assesment with the questions you are asking, ... if you think about what a Zs test is for you will understand it, you are making sure that the circuit you are working on has an earth and that it will be in the relevent limits, so if you put a immer circuit in and leave the earth disconnected then do yor Zs from a socket near by you are not confirming that your new circuit is safe!

get the nic dvd it will help, watch it loads and undrestand it, test your house as much as poss, i cannot stress how important it is to test correctly

 

[steptoe]

I suggest you follow the advice so far,

or better still,

become an apprentice and learn how to do something,

rather than spend 3 or 4 grand learning how to kill someone, and have the papers to prove you are an authorised killer.

anyone can learn to be an electrician and know how to wire a house,

the chosen few learn to be sparks and know how not to fry people.!

 

[green-hornet]

I suggest you follow the advice so far,or better still,

become an apprentice and learn how to do something,

rather than spend 3 or 4 grand learning how to kill someone, and have the papers to prove you are an authorised killer.

anyone can learn to be an electrician and know how to wire a house,

the chosen few learn to be sparks and know how not to fry people.!

I can not blame anyone who tries these courses, the system has been put in place for them to do them. I also can not blame anyone who tries to better themselves, however if I had any power I would ban these training institutions for misleading people into thinking they can be an electrician in a few weeks, and often rob them of any life savings or redundancy payments.

If anyone wants to be an electrician go to your nearest college, enrol on some proper courses, talk to local electricians who may give you some on job training, and save your hard earned cash for your family.

 

[PC Electrics]

I think the quality of the training Plonky has recieved has to be questionable. I am a natural born engineer and was able to understand the training I took easily. The training itself was also top notch. If this OP reflects acurately the standard of training at some centres, then I have had my eyes opened as to why some of you have such a massive chip on your shoulders about those who've changed careers.

The only other possibilities I can think of are that he hasn't actually got that far in the training yet (see below, this would suggest this is not the case) and is trying to jump the gun, or as originally stated, this is a wind up.

I believe, however, that there is no way anyone displaying this (inadequate) level of knowledge could ever pass an assessment and so would never be let loose on the general public.

Hi all. It's my 1st time so please be gentle. I have been installing central heating timer switches for a while now. This is my only experience in electrics. I have never done anything else electrical. Recently I went and did an electrical course to get me ready for Part-P and I am waiting for a assesor to come round from ELECSA.My question is how do you test a central heating system, ie R1, R2, ZS etc? I was taught how to test lighting circuits and ring mains and this seemed to be done at where ever the furthest point was. Do I just test in the junction box where all the cables from the stat's, valves etc join up. I apologise if this is a stupid question, but I really don't know!

Sorry matey, you will not pass. You will be questioned about testing and your lack of knowledge will let you down.

It would also be interesting to know how you managed to "pass" the course and what qualifications you gained. I did the EAL Dom Installers Cert as one of mine and remember it being 17 modules which included written tests and practical assessments (one was being assessed by the tutor at all times and had to demonstrate the necessary understanding at all stages).

So again, i question the quality of the training (and the integrity of the centre).

I did my training at 'Able Skills' in Dartford Kent