Electrical nightmares

[ians]

I get a call from a customer (i have been doing work for more than 15 years) the new boiler maker had got his mate to connect a machine... and had told the customer that whoever was doing their electrical was an idiot and had no idea what they were doing... wow not lets have a look at what might be wrong ...straight the sparkie is an idiot.

I get in my vehicle and drive to site... i am only human ...maybe i did make a mistake... imagine that ...he had the machine connected to a 3 phase orange 4 wire (not 5 wire)plug with no neutral ...so to create a neutral ...he connected the earth to the neutral point to create a neutral ...because some of us do actually use 3 phase earth leakage units on our 3 phase sockets ...there was no way on this earth that you could switch on the earth leakage ...even with all the circuit breakers off ...if you switch off the main switch it will reset ...however as soon as you switch the main switch on ...the earth leakage will trip... i pointed out the problem did a temp connection to show them it would work if wired correctly with the neutral and earth not connected ... i used a 5 pin plug and imagine that the new machine ran without a problem

[ians]

Hi Dave

1. I have never in my 41 year career as electrician come across an earth leakage tripping as a result of an earthed neutral without any current through the live.

If i were you i would get a piece of 3 core cabtyre with a plug top... put a connector on the live wire so that it is safe ...join the neutral and earth together...plug the plug top into a socket where you know the earth leakage trips at around 25 mA and come back and tell us what happens.

I would bet all my punctured bicycle tubes that there is no way on this earth that you will be able to reset the earth leakage unit with the main switch turned on ...even with the plug socket switch turned off and all the circuit breakers turned off...in fact i dont know why the clever sparkie they used to trick the fella interfered with the integrity of the electrical installation by creating a fault... he basically made the COC if there was one for that property invalid...unless he repaired it tested it again and added a supplement COC... if you can switch on the earth leakage then you have an even bigger problem ...best you get a loop impedance tester and start checking where you have an earthing issue.

[GCE]

1. I have never in my 41 year career as electrician come across an earth leakage tripping as a result of an earthed neutral without any current through the live.

I find it difficult that you could not have come across that scenario in 41 years - We come across it weekly -
Is also the quickest and quietest way to find a circuit in a commercial type environment , just short neutral and earth , reduces the amount of CB that you need to look for in a bigger DB .

[GCE]

I've asked the KZN Regional Director about this Friday last week.

I'll ask her to check with all the RDs and the Contractual Committee.

I believe that figure given by ECA was a thumb suck type figure to get to something - Mark up's vary according to contract size and desperation to win tenders and can vary from 1 % to 50% and higher when you come across Andy's situation - The tender course offered by ECA tries to teach the guys how to work out a mark up and what to take into account with regards to risks and unforeseen.

If somebody phones ECA and ask the question - "I am submitting a tender how much must I mark up " then 20% could be a safe number to throw out there with the statement "depends on the circumstances ".

If ECA had said 50% in the interview everybody would be shouting rip off , and likewise if he had said 3 % everybody would have shouted madness - 20 % seems to have attracted a bit high and others saying a bit low - Everybody prices differently , some say mark up to cover incidentals and profit , others price a mark up for incidentals and GBA , and still add profit.

I have heard of bigger MIE contractors complain because labour gets marked up by 90% whereas they would add 25 cents per person to cover admin, 50 cents for profit - If you work in small teams of 2 or 3 you need to mark up labour by 300% to cover lost time

Different horses for different courses

[ians]

Interesting... so i have customers who buy their own material ...I just do the install.

This year i will be increasing my hourly rate by an additional 10 % for those customers...actually busy with it right now ...maybe 10 % is too low....what are your thoughts ...am i being unreasonable?

There is an advantage to not supplying materials...you dont have to carry the warranty ...ie the product breaks ...they pay your full rate for you to remove and replace the item.

[Derlyn]

I find it difficult that you could not have come across that scenario in 41 years - We come across it weekly -
Is also the quickest and quietest way to find a circuit in a commercial type environment , just short neutral and earth , reduces the amount of CB that you need to look for in a bigger DB .

I did a COC inspection and testing on an installation today.

It was an unoccupied flat. I love those. No need to move furniture etc to get to socket outlets.

Tested all socket outlets with earth leakage tester. Earth leakage tripping on 25mA. In order.

Only the plugs are on earth leakage on this installation.

I then turned off the plugs circuit breakers, shorted the earth leakage neutral bar to earth and the earth leakage relay refused to trip.

Is there anyone who can explain to me why ?

I'm willing to learn.

Cheers and peace out ... Derek

[Rifrug]

Interesting... so i have customers who buy their own material ...I just do the install.

This year i will be increasing my hourly rate by an additional 10 % for those customers...actually busy with it right now ...maybe 10 % is too low....what are your thoughts ...am i being unreasonable?

There is an advantage to not supplying materials...you dont have to carry the warranty ...ie the product breaks ...they pay your full rate for you to remove and replace the item.

Hi Ians, I agree with you about charging the customer more when they supply the materials, because you will still end up wasting your time on making spares lists in your own time, and you will probably end up supplying that extra, ferrule, lug, or brother labels. Because if you have to go around and having to request these things your 4hour quoted job can become a 8hours wasted time. Also these type of customers are normally the ones who show you the other electricians quotes and offer you the job if you can beat that price. That to me is unethical but for these guys its normal bussiness.

[GCE]

Interesting... so i have customers who buy their own material ...I just do the install.

This year i will be increasing my hourly rate by an additional 10 % for those customers...actually busy with it right now ...maybe 10 % is too low....what are your thoughts ...am i being unreasonable?

There is an advantage to not supplying materials...you dont have to carry the warranty ...ie the product breaks ...they pay your full rate for you to remove and replace the item.

We generally don't work unless we are supplying material , especially domestic type installations as you tend to lose time waiting for materials or the wrong items where bought because it was cheaper.
Sometimes on bigger capital items we will allow it to slide.

Any time we do work without supplying material, I still work the price out including material , to get a feel for the job and also see what the percentages look like between labour , material , mark up and profit.
I then deduct the cost of material off my price so that I least still make the material mark up

[Justloadit]

1. I have never in my 41 year career as electrician come across an earth leakage tripping as a result of an earthed neutral without any current through the live.
Cheers and peace out ... Derek

I have experienced this fault before. I have tested this before by shorting the neutral and earth, and it did trip my ELB

[Justloadit]

I did a COC inspection and testing on an installation today.

It was an unoccupied flat. I love those. No need to move furniture etc to get to socket outlets.

Tested all socket outlets with earth leakage tester. Earth leakage tripping on 25mA. In order.

Only the plugs are on earth leakage on this installation.

I then turned off the plugs circuit breakers, shorted the earth leakage neutral bar to earth and the earth leakage relay refused to trip.

Is there anyone who can explain to me why ?

I'm willing to learn.

Cheers and peace out ... Derek

I would suspect that the distance the DB is from the transformer may play a part in this. The closer to the transformer the less likely to trip.
It may also be influenced by other loads/DBs connected to the transformer before the ELB under test.

[ians]

I started a thread to discuss hourly rates and what i would regard as a reasonable rate ...i decided to can it by the third line.

There are just toooooooooo many factors to take into consideration ...that saying... you get what you pay for... is generally right.

Are you being ripped off if the electrician charges you more than 20 % markup ...I dont think so.

Is charging a customer for the time spent travelling to the site and at double time for after hours work against the law... I dont think so.

Interfering with the integrity of an electrical installation to prove a point the way to do thing... I dont think so.

It is interesting that this got to this point ...with the technology available and considering you can access prices with the tap of a finger...you could call a 24 hr number and get a price for callouts....but even more important ...if you calling a person to do a job surely you ask the callout fee and if the figue sounds way over the top ...you shop around.

Until all the "facts" are presented in a manner in which we can see where this fella was at fault ...the bill (labour...material...travelling etc) is itemised and you can prove he has committed fraud... hear his side of the story ...I am not convinced he is 100 % to blame.

Did they get their message across and crucify him... hell yes.

[Derlyn]

If i were you i would get a piece of 3 core cabtyre with a plug top... put a connector on the live wire so that it is safe ...join the neutral and earth together...plug the plug top into a socket where you know the earth leakage trips at around 25 mA and come back and tell us what happens.

I would bet all my punctured bicycle tubes that there is no way on this earth that you will be able to reset the earth leakage unit with the main switch turned on ...even with the plug socket switch turned off and all the circuit breakers turned off...in fact i dont know why the clever sparkie they used to trick the fella interfered with the integrity of the electrical installation by creating a fault... he basically made the COC if there was one for that property invalid...unless he repaired it tested it again and added a supplement COC... if you can switch on the earth leakage then you have an even bigger problem ...best you get a loop impedance tester and start checking where you have an earthing issue.

Report back

I tried it and did everything as per your instructions.
Tested ELR with tester. Trips at 25mA. A ok.

Main switch on, ELR on, all other breakers off (no load)
Plugged in the plug with neutral and earth connected to each other as per your recommendation and switched the socket outlet on.
However hard I try, NADA, earth leakage will not trip.

Cheers and peace out
Derek

[ians]

Report back

I tried it and did everything as per your instructions.
Tested ELR with tester. Trips at 25mA. A ok.

Main switch on, ELR on, all other breakers off (no load)
Plugged in the plug with neutral and earth connected to each other as per your recommendation and switched the socket outlet on.
However hard I try, NADA, earth leakage will not trip.

Cheers and peace out
Derek

I have just tested 5 heineman earth leakage units ...all different models (old and new) ...even the one with the earth wire hanging off the bottom...every single unit trips when the earth and neutral are connected together...it makes no difference with the circuit breakers on or off...the plug switch on or off ...you cannot reset the earth leakage unit...until you remove the bridge...did a loop impedance test at the socket outlet (1.2 ohms) ...test plug trips at 24-26 mA on the various units... 232.6 volts at the plug socket.

Does the trip button on the earth leakage work.

My advice to you is do a loop impedance test at the plug socket where you are testing...if the result is within spec... then i would strongly advice you get a second opinion... it is a pity you live so far away ...i love these kind of challenges ...its what keeps me interested in the doing what i do.

I have a new challenge i am busy with at the moment ...i have clearline trip connect units installed in 2 building next to each other... one is tripping all the time (indicating low voltage 179V) the other has no event recorded... i have removed the units sent them back to clearline ...with my backup unit... they were checked at clearline and returned... reinstalled ...however the one unit you cannot set the time ...and has now gone dead... the other is installed but keeps randomly dropping the contactor out...resets after 4 seconds as per the settings in the unit parameters... and the other has no events recorded...personally i am loosing faith in these units... i should just cut my looses and replace all 3 units ...however that would be too easy

[Derlyn]

My next mission is to find out how to post photo's and videos on this forum. At the moment, I don't know how to do this.

I will then post photos and videos to prove that the ELR does not trip on a neutral fault without a load connected.



Cheers and peace out ... Derek.

[Justloadit]

My next mission is to find out how to post photo's and videos on this forum. At the moment, I don't know how to do this.
I will then post photos and videos to prove that the ELR does not trip on a neutral fault without a load connected.
Cheers and peace out ... Derek.

We do not disbelieve you.

What we are saying is that the ELB should trip, and if not, then there may be an issue at the site.

The ELB measures the difference in currents through the Live and Neutral, and if the value is greater than its specification then it should trip.
The way that this differential works, is to place the Live and Neutral through a core. The current flowing through the Live and Neutral will cancel out under proper operation. If there is a leakage in either the Live or Neutral to Earth, the currents through the core no longer cancel out, and a voltage is induced in the pick up winding.This voltage is then compared to the setting of the unit, and will trip the mechanism if it exceeds the parameter.

Short neutral to earth on a circuit carrying a load, and part of the neutral current flows through earth conductor instead of neutral. The ELB sees an imbalance and trips. So an ELB trips on almost any live fault, but only trips on neutral faults if the circuit is carrying a load.

Usually the Neutral point at the supply transformer is connected to Earth. The further one is away from the transformer, the more potential difference will be between Neutral and Earth as the system is loaded.
As I said before it may be that you are very close to the supply transformer, and hence the leakage from Neutral to Earth when shorted does not trigger the ELB.