Originally Posted By: jmyers This post was automatically imported from our archived forum.
Joe F.
I agree with Dennis and I stated that when in our original conversation. If the cable sheathing becomes disconnected you lose the ground on everything from that point and beyond. In my book, whether it agrees with the NEC or not, that is cause for concern.
I am particurally hard on the electrical issues in the homes I inspect and it is because I have come to respect the truly deadly force of electricity. While the NEC is there for mininum standards, I am there for my own standards. If I can help direct my clients into safer installations I will.
There is nothing wrong with you stating in the report that this installation is standard, typical, code compliant or whatever but there is also nothing wrong with you stating there is a better and safer method which you suggest they take.
My defense has always been and always will be, I put it in writing, WILL YOU?
I am willing to admit when I am wrong just make sure you are willing to admit when I am right! 
Originally Posted By: roconnor This post was automatically imported from our archived forum.
Now hold the phone … I’m not quite ready to let this one go yet, so I am gonna stir up the pot here a bit … I can’t disappoint Dennis or Jeff (Joe M … not that I am a disagreeable person or anything, I just like a good discussion … keeps us on our toes).
Concerning the replacement of 2-prong with 3-prong receptacles see the following link. Has NEC code references too (Note the table has 2002 NEC references, but the discussion below that table has 1999 NEC references). And it talks about upgrading a 2-prong outlet with the old style AC cable (BX trademark from GE, which does not have the currently required bonding wire/strip per 2002 NEC 320.100). Sorry Dennis, 2002 NEC 250.146(B) does permit "self grounding" outlets without the wire ... I know it's not considered good practice by most sparkies ... but we are looking from an HI point of view here.
Jeff R ... I also thought that the old "BX" trademark cable (more correctly old Type?AC cable) was from a GE plant in "da Bronx" ? but according to Redwood Kardon over at CodeCheck, the experts at GE claim they never had a plant in Bronx, NY making BX cable. Apparently, In 1911 GE gained the trademark rights to AC cable , called BX based on their class B experimental designation.
From an HI point of view I think this is a simple issue. If it is a 2-prong outlet and your newbie tester indicates there is no ground it is something to flag (you know Harry Homeowner is gonna connect that 3-prong "cheater" plug). If the tester indicated it's grounded with old style AC cable (BX) then it's just something to note and shouldn?t be flagged .. that is assuming ya checked an outlet for a "bootleg ground" and as long as the ground is not old AC cable (BX) that has some corrosion.
If the older AC cable (BX) casing is significantly corroded it no longer provides a low resistance return path for current flow, and therefore can heat up like a soldering iron. That is why the newer AC cable has an internal grounding/bonding wire attached to the casing. But, if it?s not corroded, who are we as an HI to question a previously accepted grounding of the outlet box as long as the cable isn?t deteriorated, as the code for replacement outlets only requires that it be connected to a grounded box (without any specifics that this box must meet other NEC sections if it is ?grounded? ? Dennis see 2002 NEC 406.3.D.1) ?
I know Dennis that it?s not good practice, but we are looking from an HI point of view here.
-- Robert O'Connor, PE
Eagle Engineering ?
Eagle Eye Inspections ?
NACHI Education Committee
I am absolutely amazed sometimes by how much thought goes into doing things wrong
Originally Posted By: roconnor This post was automatically imported from our archived forum.
PS. Joe M … I truely respect your position on your last post, and I like that … we are truely here to represent the safety of our client as a prospective homeowner … there just have to be limits on what we flag … the whole point of this discussion.
– Robert O’Connor, PE
Eagle Engineering ?
Eagle Eye Inspections ?
NACHI Education Committee
I am absolutely amazed sometimes by how much thought goes into doing things wrong
Originally Posted By: jremas This post was automatically imported from our archived forum.
Alright, I just have to jump in here again. I love a good technical discussion but like Bob said, let’s keep this in the perspective of the home inspection industry. There is nothing wrong with having a detailed discussion that goes beyond the HI industry so let’s step back a little.
1) If we see 2 prong receptacles in the home, then that is it, they have 2 prong receptacles and an upgrade would be desireable but not a requirement. Now, we cannot check for a proper ground with a 2 prong anyway, and unless we all carry a Fluke or other DMM (though I still miss my Simpson analog) how will we know if the box itself is grounded? This is going beyond the scope of our practice. When we are in the panel we will then know if it the old BX (no bonding strip) or if is the newer style AC.
2) If it is the older style BX with no bonding strip and there are 3 prongs installed and my tester says the ground is good then the ground is good. However, I will tell them that the older style BX that is used was never TESTED, DESIGNED or approved for use with a ground, and although it works it is their choice as to whether or not they want to rewire or replace with GFCIs. I will also tell them that there is some debate over the use and they may find an electrician that tells them it is OK. I am not.
3) If it is the newer style AC with the bonding strip and the receptacles check good then I move on to the next part of my inspection.
My inspection exceeds the standards of practice of NACHI, NAHI and ASHI and it is OK to go a little beyond. Just remember, the more technical you are in any one area, the more you are opening yourself up and the highter the expectations of the client. So if you want to start using a DMM, checking amp draws or doing calculations thats fine, buy you will be buying a big chunk of liability if something goes wrong.
Since there is controversy, the above is the position that I will take on my inspections. I will read the NEC and other publications and talk to AHJ about their position in the areas that I work. I cannot go on what a master electrician or other electrician tells me because they may be great guys who do great work, but that is all, they are not the AHJ.
Remember one thing, it is all in the presentation to the client....you can scare them or just educate them. If you scare them then your business will suffer.
--
Jeff Remas
REMAS Inspections, Inc.
Northeastern PA & the Poconos
www.NEPAinspector.com
Originally Posted By: roconnor This post was automatically imported from our archived forum.
Quote:
"In the late 30's when household appliances started to take hold, systems were often upgraded with a type of cable assembly called Armor Clad Cable (commonly refered to as BX). 2 prong outlets that are fed with BX cabling can usually be ground very easily because the metal sheathing of the cable is an acceptable grounding path."
BX is the common trade name for AC. BX was the trademark of cable made by G.E.'s Sprague Electric division.
189?- Gus Johnson and Harry Greenfield patent AC
1910- AC receiving acceptance.
1920s or the early 1930s widespread adoption.
1932 NEC- Armored cable was officially called Type AC
1952- Aluminum clad AC introduced.
1959 NEC- Aluminum bonding wire required under metal sheathing
For those not familiar with the difference between the old style AC cable (?BX?) and the newer AC cable, see this link ... also talks about some of the issues with "BX", but doesn't really go into what I think is one of the bigger issues with ?BX? which is corrosion of the casing.
Originally Posted By: jfarsetta This post was automatically imported from our archived forum.
Bravo, guys…
This is the point of my entire "nitpicking" excercise. In my view its perfectly acceptable to tell the client that there may be better ways to provide a ground. However, I think its incorrect for us to state that specific items are not permitted by Code, and are therefore defectiive, where there is still debate as to the applicability of interpretation of the Code. With all due respect, there is more data which indicates that plain BX (no ground trace) is acceptable, than not. And, Joe, BX was never considered to be flexible conduit. The difference as I understand it, is that there is no ability to pull additional conductors (or ANY conductors), through the armor cladding. Conduit provides a protected path, but is vacant.
Robert, BX was intended to proxide mechanical protction, and (later) provide a built-in grounding path. Though not acceptable by today's standards, it's viewed as an acceptable means of providing a ground path where embedded cable exists in older structures. In certain circumatances, I'm confident that it is NOT acceptable, but in homes, it is. Unless, of course, the AHJ prohibits it. The electrical inspectors are b-busters, and its okay in their jurisdiction.
As to you being right, Joe.. you are... as to ther need to put our opinions in writing.... but as opinion rather than law. I do put it in writing. No problem there. I put EVERYTHING in writing.
Jeff is also right in his assertion that we should educate rather than frighten clients away unnecessarily. There is a clear difference.
Robert, you master of pot stirring, nice job of playing Devil's advocate...
Originally Posted By: jmyers This post was automatically imported from our archived forum.
Joe F.
MC style cables are considered flexible conduit. There is very little difference between the two both use interlocking style metal. The difference between the two would mostly consist of the wires being preinstalled in the MC style cables and the flexible conduit is void and comes in different sizes. If you were to take a look at the 3/8 greenfield and the MC style cable you will see the only differnce between them in that one has wires the other does not.
If I were to call american wire and ask them the difference they would tell me that one comes with wires and the other does not! BTW... I used to work for an electrical distributor and both of those products were typically purchased from the same company, came in on the same truck which was shipped from the same manufacturer! If it was not for the weight and the wires sticking out on the ends you can not look at the two and tell them apart. They are exactly alike.
If you want to argue you have come to the right place!  Maybe I am not explaining this well enough for you to understand. Ok, with wires it is called MC, without wires it is called greenfield. MC is greenfield with wires, greenfield is greenfield without the wires. BTW...greenfield in the name of the dude that first manufactured it.
HE HE HE HE HE, sorry I just could not resist! 
Originally Posted By: jremas This post was automatically imported from our archived forum.
See,…Now aren’t you guys happy I started this thread and you stopped beating the dead horse with the double taps?
This so far has been extremely informative. Bob O has given us some great insight and Joe F has made us think a little more. Look how much we all learned from this tiny little topic. I hope we can continue several others soon.
Thanks,
--
Jeff Remas
REMAS Inspections, Inc.
Northeastern PA & the Poconos
www.NEPAinspector.com
Originally Posted By: jfarsetta This post was automatically imported from our archived forum.
This is why our org is growing so fast. We’re never afraid to stick our fingers in the fan, even when Joe Myers has his hand on the switch!!!
Good point, Jeff.
I, for one, am grateful I have compadres who are willing to look at things from all sides, and can learn from each other. I have learned from this thread, for sure...
Originally Posted By: jmyers This post was automatically imported from our archived forum.
i just received this excellent post from an electrician on the Mike Holt BB. I hope this would clarify all those, like myself, that are confused about BX style cables and whether is should be flagged.
posted September 27, 2003 10:01 PM
Joe, I always test for armor continuity - even on new AC. It its NOT there, then there's an issue somewhere in the system that needs to be rectified.
This is just part of my own personal testing ritual. I've got one of the new Ideal AF/GF units and use its line status functions extensively. Its pretty good at finding branches with loose splices too. The L/N/G ohm readings will seem abnormally high. It indicates open grounds and a whole bunch of other issues. For the old non-bond wire BX and two-prong plugs I'll use a 3-prong adapter and gator clip to box. Its a wonderful diagnostic tool for determining the health of a branch.
On the old non-bond wire stuff, if there's no continuity to the panel, then the GFCI only buys you "people protection" against shocks. While people protection is all well and nice, its not buying you the line-armor neutral-armor short "wiring system protection" that a system with continuity would. Armor could still be energized by a failed hot wire insulation somewhere and go undetected by the GFCI (until someone grabbed it and created a leakage path).
IMO, if you have the old non-bond BX, and a GFCI breaker, and the branch has tested out as having continuity, then yes indeed it is “SAFE”. Deteriorated insulations where something contacts a box or even internal to the cable on hot or neutral will leak enough to trip the GFCI (it has been my experience that the insulation degradations are mostly within boxes and an inch or so back inside the cable. Take a fresh 8" bite on some of the old stuff when there’s enough slack and it’ll strip off looking pretty darn good in most cases). When there’s NOT enough current flowing on the armor to trip a 5ma GFCI, then there’s certainly not enough current flowing through the armor back to the panel to cause it to become scorching hot and start whatever its fastened to on fire. In essence, the old stuff is electrically not much different than a no ground wire hot/neutral pull through long sections of Greenfield.
Posts: 55 | Registered: Sep 2003 | IP: Logged |
Many thanks to Toni that posted this message. 
Originally Posted By: Dennis Bozek This post was automatically imported from our archived forum.
I’m back!! Did ya miss me
Still beating up the bx issue huh....when I was in the Marines we called it a PX...and the army called theirs a bx...not sure what the fly boys called theirs...oops...wait we are talkin electrical stuff...sorry:lol:
I know all about the codes....yea bx is ok....but sorry guys....to me it is not ok. At the time anyone tests it....it checks out good. Nice solid continuity back to a properly grounded panel. Acceptable for a ground? Sure! But what happens if after you tested it, it corrodes...or mom hangs some clothes on it and it pulls out of it's connector? Still a good grounding source? NOPE!
Why?
It's corroded...not making contact...or it is out of it's connector....not making contact!!! At the time it was not corroded or it was tight in it's connector.....it was ok.....but as soon as it corroded......or was pulled out of the connector....this so call good ground became bad!
If there was a EGC in that piece of greenfield, or BX....then it can corrode all it wants to.......it can be yanked, tugged and pulled from it's connecting device all it wants to.....it can even be used as a place to hang clothes and guess what....the device will still be grounded due to the fact that there is a EGC installed. So with a vital issue such as grounding, why would you as a HI not question the integrity of a ground when using bx or greenfield for the grounding source?? I just gave you a few reasons why you should question it. Yea Yea....the code says this and the code says that....and Dennis says "No way Jose"!!
Have I ever used BX or greenfield as a grounding source? Yep I have but only in cases where it would be near to impossible to run a egc to a device and in such cases, I informed the customer that although this installation will provide a ground to this device...if it ever should become corroded or pulled from it's connection device....the ground would then be lost, thus providing no ground protection. I leave it up to them at that point to decide on leaving it or making it right...so that the ground connection is never compromised. 90% of the time, when they hear what it will cost to run a separate egc to a device....they say....naw leave it...it won't corrode or get pulled out.
-- This information has been edited and reviewed for errors by your favorite resident sparky.
Originally Posted By: jremas This post was automatically imported from our archived forum.
Hey!! What’s up with these replies?? I thought what I said was the gospel around here. Dennis “shower shoe” B. not looking for your opinion on BX, we want facts. Even though your opinion is shared by myself & some others from what I have read. We want facts.
BX not rated when originally built, therefore no clear answer to say that is is OK to use as a equipment ground. When in doubt, err on the side of safey and the answer is NO BX for a ground.
AC cable, designed and approved whether anyone likes it or not. Bottom line is that the code allows it. If an local AHJ wants to stiffen the rules and not allow it then that is their place to do so.
MC cable already has a separate ground so why are we even bringing it up?
Do I have to keep everyone in line around here??
In Fun,
Jeff
--
Jeff Remas
REMAS Inspections, Inc.
Northeastern PA & the Poconos
www.NEPAinspector.com
Originally Posted By: jfarsetta This post was automatically imported from our archived forum.
Jeff,
You'd fail nearly every old house you inspect in NYC, babe. Romex, or any other non-metallic sheathed cable for that matter, is prohibited.
Inspected a home for a service person (inspector) for Con Ed last Saturday. No tracer in the BX. Its allowed. BTW, Con Ed shuts the power to the house off if they see a significant code vioation...
Originally Posted By: roconnor This post was automatically imported from our archived forum.
Having a low impedance ground-fault current path is important for a 2-prong with a cheater plug, a standard 3-prong, and for a GFCI receptacle where there could still be a hot to casing short problem as Joe M?s post pointed out. The impedance/resistance can be checked by a sparky with various high-end plug-in testers/analyzers.
The link mentions a 1.0 ohm maximum ground resistance, which I have heard elsewhere as a check on older AC cable. But this kind of electrical testing is beyond a standard home inspection and should be done by a sparky. The way I read the NEC, an electrician is really required to check out and connect a ground if available like in older AC cable. As Joe F indicated, vintage AC is very common in our area and it's just not reasonable to flag every one ... we need facts.
-- Robert O'Connor, PE
Eagle Engineering ?
Eagle Eye Inspections ?
NACHI Education Committee
I am absolutely amazed sometimes by how much thought goes into doing things wrong
And how do you know a cable doesn't have an internal bonding wire (similar to newer AC cable) ... that seems to be an NEC requirement since 1959. This bonding wire can be cut off at the box connector and you may not see it.
I think the real issue is making sure there is a ground and making sure you perform a visual examination for deterioration and casing corrosion. If a cable has been in place for a while without significant problems, it's not just going to fall apart the minute you leave the house.
Unless there is evidence indicating otherwise, I do not think it is reasonable to flag vintage AC cable. But it should be noted and you may want to advise your clients of the potential issues so they can decide if they want an electrician to come in and test/evaluate the wiring system anyway.
-- Robert O'Connor, PE
Eagle Engineering ?
Eagle Eye Inspections ?
NACHI Education Committee
I am absolutely amazed sometimes by how much thought goes into doing things wrong
Originally Posted By: jfarsetta This post was automatically imported from our archived forum.
Now for the monkey wrench…
Some REALLY OLD BX cable actually used a form of asbestos for the insulating material, which sometimes appears like cloth... How's that for a happy piece of news? So, guys... we've BEATEN this grounding thing to death...
