Testing...how far do you go?

D

Dave 85

Be honest here guys...When you do your testing, do you do it exactly the same as you would during a college assessment on every installation you work on/install
I dont, and I've never known a sparky who does
Feel free to accuse me of being a cowboy but here are the things I do different...

If im IR testing an old install and I get, say 50Mohms across the main Neutral/Phase and earth bars I'll write down every circuit as >200 rather than rip the fuseboard apart trying to find the circuit/circuits with less than 200. It doesn't really acheive anything IMO and takes time..
I never IR 500volts between L and N on an existing installation if the reading to earth is good, the risk of damaging the clients property is too great IMO

If im testing a new ring circuit installed by myself I'll test end to end on all 3 conductors but won't carry out cross connected ring continuity tests. On my own circuit I know its wired as a ring so this test is completely pointless.

On my own installations, if I know the chances of parallel paths etc are zero I sometimes gain my R1+R2 reading for a radial by testing Zs at the furthest point and deducting Ze. IMO this proves beyond all doubt you have a good R2. Now I know you're supposed to prove the circuits are compliant before energizing but we're all trying to make a living here and whats the worst that can happen when you know you do good connections every time and its all RCD'd

Also when I do a consumer unit change I do not test and inspect the installation to the same extent as I would an EICR. I just test ring end to end, IR L/N-E, RCD time, Ze and Zs at the end of each circuit-The going rate for C/U's (£350) does not really allow for a whole day of testing and inspection and the house is gonna be 10 times safer than before I turned up anyway.

Hopefully this should arouse some fiery debate
Seems a bit of a case of common sense vs blindly following the rules you've been given without questioning the neccessity....
 
Do rcd tests at the board with all mcbs turned off to reduce " electronic noise " from appliances.
2 rcd CU = 2 separate tests at the device.

Aye bloody obvious really, I've been doing it that way a while now, Was taught at college to RCD test every circuit. Nonsense
 
i tend to test RCDs at sockets. reason is that i generally use the auto test function and it's not easy to keep probes in contact with the RCD terminals whilst resetting the RCD after each trip. also, IMO, in the real world thae RCD is expected to trip if necessary with circuits and loads connected, so why test with circuits OFF. ?
 
It's your name on the cert not anyone else's so you do what YOU think is necessary.

Shock horror I sometimes do no IR on a CU change instead I bow to the good old bang test.

However I never leave a job without being confident that it is safe.


There I was honest.
 
i tend to test RCDs at sockets. reason is that i generally use the auto test function and it's not easy to keep probes in contact with the RCD terminals whilst resetting the RCD after each trip. also, IMO, in the real world thae RCD is expected to trip if necessary with circuits and loads connected, so why test with circuits OFF. ?

I like this method too. Much easier to plug in MFT and place on floor or kitchen worktop and leave on auto test and not be trying to hold probes and reset the RCD.
 
.......... so why test with circuits OFF. ?

The rcd manufacturers themselves recommend the testing is done off load.
Some brands are suseptable to give inaccurate readings if loads are active downstream.
In many cases it doesnt make much difference but that is the guidance given anyway.
 
Last edited by a moderator:
wow a very good honest chat i'm impressed indeed . i've always thought this site should be called to good to be true electrics .

its a weight of my mind i thought i was the only one living in reality
 
Do rcd tests at the board with all mcbs turned off to reduce " electronic noise " from appliances.
2 rcd CU = 2 separate tests at the device.


or


Switch Off all loads at their switches
Use Plug-Lead of the MFT on auto-test to test the RCD's, at the most convenient socket
 
wow a very good honest chat i'm impressed indeed . i've always thought this site should be called to good to be true electrics .

its a weight of my mind i thought i was the only one living in reality
Yes, I totally agree. It didn't start too well, I thought I was gonna get hung out to dry after the first 5 responses from incompetent illiterate fools, but the naysayers have gone suprisingly quiet since the proper sparkies who know what they are about have spoken up.
 
It's your name on the cert not anyone else's so you do what YOU think is necessary.

Shock horror I sometimes do no IR on a CU change instead I bow to the good old bang test.

However I never leave a job without being confident that it is safe.


There I was honest.


Well said!
I have to say, mind, that recently I have taken to IR testing each circuit as I go when doing a C/U change just to prevent myself tearing my hair out when I turn it on the RCD'd wont hold.

The guy I used to work for, when 17th ed boards first came out, on several occasions, replaced both rcd's with main switches after a CU change because he couldn't ever work out how to get them to hold in and fault finding was completely beyond him. Have you ever heard anything like it? Its insane.

For the record he did a full 2360 apprenticeship, AM2, 16th edition, NVQ the lot. Far more qualified and experienced than I ever was.

He went bankrupt three years ago in a year where he turned over about £150-200k with just me and an apprentice.

Proof that incompetence catches up with everyone in the end....
 
Alot of good sparks dont get their heads round testing , which is why 2391 has only 30% pass rate.
Of course i did mine back in '97 when the exams were really hard :-)
 
Yes, I totally agree. It didn't start too well, I thought I was gonna get hung out to dry after the first 5 responses from incompetent illiterate fools, but the naysayers have gone suprisingly quiet since the proper sparkies who know what they are about have spoken up.

you started this thread as a wind up,as for being called a incompetent illiterate fool,Ihave worked with some right nobs
who don't give a stuff about looking out for them selfs or anybody else,so in my case because i work on forecourts & fuel storage depots with petrol/diesel, i am a little sensitive to people not working safely.
 
Interesting thread: I am from the earlier version of sparky (industrial background)
Anything new and anything i have not installed gets full 500V treatment - so does anything like a simple radial where i am confident i know exactly what the cct is and there is no chance its spured off anywhere.
Everything else gets 250V - this has saved me numerous times when i have subsequently found additional equipment.
I spend at least half my time on visuals and making sure i have found everything i can. This is no mean feat in a factory environment with so much electrical equipment fed from control panels rather than from Dbs.
RCDS tested from nearest socket with MFT on auto.
Grouped IR numbers repeated across whatever group i have done.
I usually find i have to get my hand into the board so when i have finished i generally put the DB cover back on and do Zs tested to ensure i have not put a fault on and then test the device.
I am not generally testing to a fixed price but overall i am more likely to mess up on missing a broken socket / switch/isolater etc etc that fails basic insulation of live parts as is the environment i am working in so this takes my priority. To be honest if i cannot find a circuit it goes down as "not found", if i cannot get an IR reading cos i know there is sonmething plugged in out there, it goes down as Limitation with comment. If stuff is too high to reach - ditto.
Don't do much house stuff but suspect IRs on sockets and lights could be interesting.
Much of the work i do is live, whether i am in a DB adding ccts or testing. I work as if everyhting is live and rarely get a belt (mostly off neutrals).
If i am working on lighting i am more likely to work live as i hate being in the dark so will always try and keep the lights on - TBH its no big deal and i honestly cannot see what all the fuss is about, after all its only 240V !!
 

OFFICIAL SPONSORS

Electrical Goods - Electrical Tools - Brand Names Electrician Courses Green Electrical Goods PCB Way Electrical Goods - Electrical Tools - Brand Names Pushfit Wire Connectors Electric Underfloor Heating Electrician Courses
These Official Forum Sponsors May Provide Discounts to Regular Forum Members - If you would like to sponsor us then CLICK HERE and post a thread with who you are, and we'll send you some stats etc
Back
Top