Loop Impedance Test

[mbrooke]

I refuse to accept the need for the things you want.

I refuse to believe the fact an item or test procedure exists is a reason to mandate into code

These concepts should be considered and tested before being disregarded. Condemnation without investigation is the highest forum of ignorance.

I am not advocating they be mandated into the code, however further investigation is worthy. The fact so many codes require testing raises a flag. Even bare bone codes that let most anything go require testing. If this method does indeed help with the practical safe guarding of life and property its worth using it field.

Tony asked me the exact same question not more than a couple of weeks ago, he asked I answered and then he asked again in this thread. I am not going to keep answering the same question.

And you still kept insisting they nuisance trip by taking his words out of context despite him saying otherwise. When he kept explaining they do not nuisance trip you simply bailed and then kept posting the same. If you can discredit someone who works with RCDs first hand on a daily basis (as well as knowing others who do the same) while you (probably) have never even seen one in real life clearly speaks for itself. I dont think you are here for an honest debate or discussion. Either that you do not want to admit being wrong.

I did not disagree with that view.

Part of the problem is you make your posts so damn long and covering so many topics in one post makes it very difficult to respond via moble.

My posts were long because the topic being discussed which was (AFCIs).

Perhaps you should do some more self examination.

Please, I am ok. I do not want to be Ego driven, that would be an awful fate. Id rather see the whole picture while knowing where I am wrong and where I am right.

For example, main RCDs you will tell me that the fact they use them in Europe is all the proof we need to justify main or sub main GFP here. That's your proof, that and your personal feelings.

I never said it was all the proof or justification. I brought up main RCDs because they are a cheaper way of providing protection and my intent was to have the concept debated in the forum if its worth or not being considered here as a cost saving alternative. So far I heard two good reasons against them which is what I wanted to see.

When people point out that sub main GFP at the trip levels you advocate would cost the consumers more you simply ignore that or try to say troubleshooting won't be needed.

Again, you keep insisting those trip levels are inadequate to cover your nuisance tripping claim which Tony knows is wrong. Whether we use 50ma of 4 amps, if a fault is on one circuit it will trip the GFP. 8 typical circuits with typical electronics are not likely to ever produce leakage currents over 25ma, so a 50ma RCD will hold just fine and only trip for a fault.

That is not proof of a need for sub main GFP, I know you are sure it is but many of us experienced folks disagree.

It is proof that either testing or some type of GFP is needed. I can buy the arguments a sub main GFP would be to much burden when an issues actually arises, so individual GFCI or GFPE beaker would be the way to go.

But no one can deny new homes (as well as buildings) are being built with wiring errors. 1/2 the AFCI nuisance tripping claims come from GFP, and every one of those homes now has an electrical system thats safer then it would have been without GFP.

 

[iwire]

QED more house fires

Tony, I could not possibly be concerned any less what a 40 year English industrial electrician has to say about American dwelling unit wiring practices.


That is not to say you could not teach me about industrial controls or wiring practices but your knowledge of our dwelling unit wiring is zero.

 

[mbrooke]

No I can not, Don has mentioned it a few times. You could try asking him.

It's $325 to download so I am not that interested. :happyno:

Or you could down loaded it here for free


iwire removed link

If you know the section I will happily go through it.

 

[user 100]

These concepts should be considered and tested before being disregarded. Condemnation without investigation is the highest forum of ignorance.

I am not advocating they be mandated into the code, however further investigation is worthy. The fact so many codes require testing raises a flag. Even bare bone codes that let most anything go require testing. If this method does indeed help with the practical safe guarding of life and property its worth using it field.

Heres the thing-they have been considered. Debating ELIT being utilized in homes over here isn't anything new and it has been studied and decided that that solution isn't really applicable to our situation and I agree. To understand this mbrooke, one must look at exactly what an egc does and if its continuity is that critically important in most situations when its needed. Most devices in a home have a 1-15 cord cap and do not take advantage of an egc, so if an egc gets dropped where it isn't likely to be needed anyway....you see where I'm going.

Most other areas of a home that would contain accessories that would need an egc (kitchen, outdoors, garage, etc) are already largely protected by a gcfi that doesn't need an egc to function-true having an intact egc tied to that gfci would be more ideal, but still. So where is the need for a lot of this testing in a new house?

There is NEVER a reasonable excuse for a loose joint of any kind in a home, but invariably its going to happen-remember humans still install electrical systems and some of those loose joints aren't as dangerous as others. And those same humans can also falsify an ELIT result.

 

[don_resqcapt19]

...A fire developed in a panel just last week in my neighboor. The cause determined was loose breaker jaws. Anyone who has worked in the trade a long time has seen this problem happen countless times. ELit testing would pick out this problem before it occurs.

How old was the installation? What makes you think a test at the time of installation would have prevented this?

 

[don_resqcapt19]

Can you post what section you are referring to?

I am not sure of the section in their code, but their equivalent to 300.20(B) does not apply under 200 amps.

 

[iwire]

For the simple reason you can’t answer the question.

Tony, you asked me the same question about 3 weeks ago, I answered the question at that time.

It's not my job to keep answering it.

 

[iwire]

Or you could down loaded it here for free


iwire removed link

If you know the section I will happily go through it.

We do not allow those links here.

 

[mbrooke]

One of our regular service accounts has some branch circuit hots and neutrals scrambled between conduits. No smoke, no fire, no shocks. Sure it needs to taken care of, but it has been that way longer than I have been alive.

Of course, do you really believe the blanket rules for 14, 12 and 10 gauge wire along with already conservative current carrying capacities are an accident? :lol: The CMP knows nothing is there to prevent inductive heating of conduits, hence the extra safety factor. No matter what we pay for it, one way or another.

 

[iwire]

I am not sure of the section in their code, but their equivalent to 300.20(B) does not apply under 200 amps.

It looks like it might be 12-106(5).

 

[iwire]

The CMP knows nothing is there to prevent inductive heating of conduits,

So you don't believe 300.3(B) exists? :huh:

 

[mbrooke]

So you don't believe 300.3(B) exists? :huh:

300.3 (B) does exist, and thats to knock down the risk during installation. However the CMPs know that 300.3 (A) & (B) does not remove all inductive heating risk, hence another motivation to increase the safety factors built into current carrying capacity tables.

 

[mbrooke]

It looks like it might be 12-106(5).

Id quote that section if you allow me to, but my understanding is (5) applies to a single conductor cable? A single conductor can dissipate heater better then multiple conductors.

 

[iwire]

, but my understanding is (5) applies to a single conductor cable? .

It looks like it, I am not a CEC expert.

A single conductor can dissipate heater better then multiple conductors

The heating of the conductor is not the issue, it is the heating of the material it passes through is the issue.

 

[iwire]

300.3 (B) does exist, and thats to knock down the risk during installation. However the CMPs know that 300.3 (A) & (B) does not remove all inductive heating risk.

IMPO you are not making a bit of sense here.

 

[growler]

IMPO you are not making a bit of sense here.

That means that Mbrooke is probably planning to run for some high political office in the next election and is just getting warmed up. :lol:

 

[Tony S]

Tony, I could not possibly be concerned any less what a 40 year English industrial electrician has to say about American dwelling unit wiring practices.


That is not to say you could not teach me about industrial controls or wiring practices but your knowledge of our dwelling unit wiring is zero.

I know nothing of your wiring methods? YOU know absolutely nothing about me.

The moderators on the forum I run have a rule, “Get to know the members”.


Amongst the boring things I had to study was “test methods and reliability”. Strangely enough it didn’t just cover industrial systems. Control of the AC arc was particularly boring until things like AFCI’s rear their ugly head.


PS, I’m a qualified teacher. Anytime you’re ready to learn I’ll teach.

 

[mbrooke]

IMPO you are not making a bit of sense here.

300.3 (A) and (B) do a good job of reducing inductive heating from a physical wire routing standpoint, however 300.3 will not prevent or stop inductive heating from a grounded neutral.

 

[mbrooke]

I know nothing of your wiring methods? YOU know absolutely nothing about me.


Amongst the boring things I had to study was “test methods and reliability”. Strangely enough it didn’t just cover industrial systems. Control of the AC arc was particularly boring until things like AFCI’s rear their ugly head.

The moderators on the forum I run have a rule, “Get to know the members”.

PS, I’m a qualified teacher. Anytime you’re ready to learn I’ll teach.

Im ready to learn

 

[iwire]

I know nothing of your wiring methods? YOU know absolutely nothing about me.

The moderators on the forum I run have a rule, “Get to know the members”.


Amongst the boring things I had to study was “test methods and reliability”. Strangely enough it didn’t just cover industrial systems. Control of the AC arc was particularly boring until things like AFCI’s rear their ugly head.


PS, I’m a qualified teacher. Anytime you’re ready to learn I’ll teach.

And I believe you.

Yet still you are not an electrician here and you don't wire homes here. To me that makes you an observer that has no business telling us we are doing things wrong.