BX and ungrounded receptacles

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41

Originally Posted By: jremas
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Rob O, once again you bring up some very valid points,…thank you. I knew we could keep this thread alive. I would have to see the test results on impedance of the older style BX. Most that I see do not have an internal bonding strip. I just removed some from my 1960 home and it had no bonding strip when I unwound it. IN MY OPINION I would prefer to see AC cable with a bonding strip used and NOT the older BX without a bonding strip. I hope that someone can contact the manufacturers of the older BX with no bonding strip to see what the impedance test results were.


Now on to you Joe F.,...... I do not pass or fail any home. Never, no way, does not happen. Why? Because there is no such thing as pass or fail with a home inspection. I simply inform clients of the conditions of a home and let them decide what they want to do about it. That's it!! A code enforcement officer can stop a job or make a contractor change something if it does not comply with the current code during construction or remodeling, a local code officer can do an inspection on a property transaction if their by-laws allow and decide if a home is livable or not. We cannot make any decisions for the occupancy of the home. I have looked at pieces of garbage that should have been torn down 20 years ago but someone wanted to buy it. I just give them facts and they can take it from there. They have the option to accept as is, make repairs after purchase, try to get the seller to fix the problems or just walk away from the deal. Every buyer is different. Some will get upset about fogged windows when a seal is leaking and others live to do work and want a project....it is their lifestyle.

PASS or FAIL is completely subjective and not to be decided by a home inspector. In the worst cases my report states that "This is a safety hazard and correction is needed" I never say it is a violation because we are not enforcers.

OK, I am hopefully finished getting wound up this week and will let everyone alone. Hey Bob O, how about my post on "interior" about the beams? Looking for some response from youu!!

--


Jeff Remas
REMAS Inspections, Inc.
Northeastern PA & the Poconos
www.NEPAinspector.com

570-362-1598

42

Originally Posted By: roconnor
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hmmmmm … 1960 house with AC cable that has no bond wire/strip. Either the 1959 reference I saw is off, that code revision didnt get adopted by your municipality until after 1960, or the contractor used up some old spools of outdated AC cable on your house (not that it ever happens) … icon_rolleyes.gif


So no one has anything concrete for supporting a flag on vintage AC unless its deteriorated or the casing is corroded? I might buy that, particularly since from a "visual observation" it would be hard to tell if there was a bonding wire/strip and it is beyond a home inspection to start using sophisticated electrical testing equipment or evaluating electrical test results.

I like to use the "Harry Homeowner" rule ... where I don't use equipment or tools that a typical homeowner wouldn't consider using.

--
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

43

Originally Posted By: roconnor
This post was automatically imported from our archived forum.


P.S. Since tools came up, I added a topic about this:


http://www.nachi.org/bbsystem/viewtopic.php?p=12218#12218

Seemed like the better place to discuss this issue of tools for an HI. Yea, I know ... oh well ... ![icon_biggrin.gif](upload://iKNGSw3qcRIEmXySa8gItY6Gczg.gif)

BTW ... The "fishing lure" outlet tester I use is a GB Sure Wire. Has the usual 3 bulb checks, as well as a check on a bad ground (in addition to open ground). I thought about asking GB if this uses the 1.0 ohm resistance rule. Anybody know?

--
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

44

Originally Posted By: Dennis Bozek
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Havent we beat this subject up enough lol icon_eek.gif

–
This information has been edited and reviewed for errors by your favorite resident sparky.

45

Originally Posted By: jremas
This post was automatically imported from our archived forum.


Ok, time to bring this subject back from the dead & archived:


Alright,...... The expensive SureTest told me there was no ground on a brand new self grounding receptacle that I put in in MY OWN home. I checked the connections and the ground screw including the BX clamp and all was tight. I traced the wires to the only junction box and the clamps were tight there too. Checked the connector and connections at the box. Still showing NO GROUND. Note-the cheap 3 prong tester said it was good the whole time.

I got out some trusty bare 12awg and you can see what I did. POOF, works like a charm.

![](upload://hT65xxFA2qZ7ueaWFsh2IdLNgPv.jpeg)

Mr. SureTester from Ideal says the circuit now tests OK.

Lessons:

1) You really can't trust BX to provide it's own equipment ground.
2) The SureTest works better than the 3 light plug in jobbies.
3) Homeowners will do whatevery they have to ... to make things work.

More comments?

BTW, I was too lazy to pull new cable because the receptacle was mounted on an exterior wall and my home is a block home with furring strips and rock-lath. The box is set into the block.

--


Jeff Remas
REMAS Inspections, Inc.
Northeastern PA & the Poconos
www.NEPAinspector.com

570-362-1598

46

Originally Posted By: Mike Parks
This post was automatically imported from our archived forum.


Jeff


Let me throw this back at you.

As a HI how would you report this to your client? ![icon_smile.gif](upload://b6iczyK1ETUUqRUc4PAkX83GF2O.gif)

More comments--- you mean the transformer? ![icon_smile.gif](upload://b6iczyK1ETUUqRUc4PAkX83GF2O.gif)

Mike P.

47

Originally Posted By: roconnor
This post was automatically imported from our archived forum.


OMG … It’s back from the dead … icon_eek.gif


Having fun with your new "toy" I see, eh Jeff ... ... Did you figure out (hopefully not the hard way) that it will give you a "False Ground" on outlets close to the panel yet, even if everything is okay and there are no "sneaky jumper" bootleg grounds?

Nice "bonding jumper" to "fix" the problem. From what you describe, I would bet the ranch that you had a marginal connection at that box which is giving you a somewhat high resistance ground path (one of the possible problems with using AC cable as a ground, including the old "BX" type).

The SureTest uses a 1.0 ohm limit on ground resistance, beyond which it will flag you. But I thought the SuteTest would read out "BAD GROUND" instead of "NO GROUND" in that case. Some say that is a little low for an older existing install, and a number in the 2-3 ohm range is more reasonable (without considering sensitive equipment protection). I would be curious to know what the actual ground resistance is without your "bonding jumper" if ya can do that without killing yourself ...

Doesn't mean BX can't be used for a ground, just that you had a bad/marginal box connection. The exact same thing could probably happen with newer AC cable, which also uses the casing as the ground (ECG) and is done all the time in compliance with current model codes.

In any event, I think thats an example of why I am a fan of at least using a better grade 3-bulb outlet tester like the GB SureWire, which also will check for a bad grounding path.

Just my 2-nickles

--
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

48

Originally Posted By: jremas
This post was automatically imported from our archived forum.


How would I report this to a client? A home inspector would probably never see this during a home inspection. If I did see it, I may not know why it is there and it may not even go on my report. The receptacle would have checked good and I would have moved on unless there was no cover on the box or there were loose wires.


Bob O, I actually don't remember what the SureTest said, I just know it there was something wrong with the ground. The problem was solved after my little bonding method.

Do you really want me to disconnect it and get my Fluke out?

--


Jeff Remas
REMAS Inspections, Inc.
Northeastern PA & the Poconos
www.NEPAinspector.com

570-362-1598

49

Originally Posted By: jmyers
This post was automatically imported from our archived forum.


Mike P,


I use the cheapo three prong tester that Jeff is talking about. If the run of BX is longer than 6 feet and has grounding style receptacles it would be called a defect.

Joe Myers

50

Originally Posted By: rpalac
This post was automatically imported from our archived forum.


I can’t stand back…


As a commercial/industrial electrician I can't sit by idol....

There is nothing illegal about the sheathing of BX being used as a ground.

There is nothing wrong with a non-grounded receptacle.( 2 wire as it is referred to).

There are circumstances that do make the issues wrong. Such as changing a non-grounded receptacle to a grounded receptacle with out adding the grounding conductor.

If the system exist when it was acceptable by code via 1964, 1979, 1999 code it is grandfathered and okay.

Do you expect me to remove every piece of BX I installed in all teh Acme's 2 Penn-Center, the IBM building, Commerce Square, ....I don't think so.
They are all fine.
AS Jeff F. Pointed out it is acceptable and we are stepping further than we should.

If there is corrosion then it is our duty to write it up. If there is a no-ground or boot leg, or reversed polarity, then we write that up.
If it is a non-grounded system then we suggest that be upgrade for safety. But we can't red flag it.

If the GFI's are not there then we write that up according to the municipality requirements. Not ever municipality requires GFI's every where. You do not have to bring a house up to the most modern code that is out. NEC Article 80.9 (A), (B) and (C).

I have been doing consulting for the last 20+ years, half the time it is in defense of a home owner who was selling a building and someone wrote up a requirement to change things that were supposedly illegal or not to code. Be careful what you qualify as not acceptable.

BX if installed as it was intended is Okay. If it has signs of corrosion , it is not okay.

Some receptacles do not have to have a ground wire connected to them they are manufactured as previously described to be self grounding.


Sorry....I get very defensive on electrical issues.............

I guess we all want the world to be modern and perfect but reality is that we have to accept the issues we have from the past. We just need to know what is safe and unsafe.


Knob and tube is safe. It's when you have some one getting their grubby little paws into the box and screwing it up.

Boy...I'm sure I got some people mad with this reply.
Bob P.

51

Originally Posted By: jmyers
This post was automatically imported from our archived forum.


Bob P,


Are you referring to me? If so, I would be more than happy to clarify my statement.

Joe Myers

52

Originally Posted By: Bob Badger
This post was automatically imported from our archived forum.


rpalac wrote:

As a commercial/industrial electrician I can't sit by idol....

There is nothing illegal about the sheathing of BX being used as a ground.


Well that depends, there is no BX in the NEC there is AC and if you are taking about modern AC cable with the internal bonding strip as required by 320.100 I agree 100%

Quote:
320.100 Construction.
Type AC cable shall have an armor of flexible metal tape and shall have an internal bonding strip of copper or aluminum in intimate contact with the armor for its entire length.



rpalac wrote:
Do you expect me to remove every piece of BX I installed in all teh Acme's 2 Penn-Center, the IBM building, Commerce Square, ....I don't think so.


Heck no, ![icon_smile.gif](upload://b6iczyK1ETUUqRUc4PAkX83GF2O.gif) that old type AC or New type AC it is fine as it is existing and as you say is grandfathered in.

Now let's talk about adding a grounding type receptacle to old style AC that does not have the internal bonding strip, as far as the 2002 NEC is concerned that old type AC is not one of the EGCs listed in 250.118.

It would be a violation for me to use the old AC as an EGC for work I do today.

rpalac wrote:
Boy...I'm sure I got some people mad with this reply.
Bob P.


Well you will not make me mad as I can still do as I want at my job and I will not make an installation today or in the future that relies on the old style AC for a ground. ![icon_smile.gif](upload://b6iczyK1ETUUqRUc4PAkX83GF2O.gif)

--
Bob (AKA iwire)
ECN Discussion Forums
Mike Holt Code Forum
53

Originally Posted By: rpalac
This post was automatically imported from our archived forum.


NoJoe, I am not pointing at you.


I am responding to different comments made. We seem to pick the fly doo-doo- out of perrer though, don’t we.


I just take issue to when we speak as an authprity on a possition about an installation and not all the facts are correct.

an example: An inspector red flagged a panel because the pannel was a Murry with Challenger , Murry, and Seimens breakers. The comment is that the breakers had to be the same as the panel. This is not true.

The fact that BX sheathing is not an acceptable ground. That is not true.

Recepticles must have a ground prong. Not true.

Grounding receptacles must have a ground wire and can not be self grounding. Not true

There are a lot of mistakes that we stand behind treating then as correct, when in fact there not.

So no Joe....this isn't about you. I just am making a general statement. As a matter of fact, i thought you are a sparky also.

Maybe, I just got my feathers upand came across incorrectly. My apology.

Gosh, I know I'm wrong alot and I get snagged with it.

Bob p.

54

Originally Posted By: Bob Badger
This post was automatically imported from our archived forum.


rpalac wrote:
an example: An inspector red flagged a panel because the pannel was a Murry with Challenger , Murry, and Seimens breakers. The comment is that the breakers had to be the same as the panel. This is not true.


The only time this is allowable is if the breakers are UL classified for use in the panel they are installed in and the available fault current is under 10K

2003 UL White Book
Quote:
CIRCUIT BREAKERS, MOLDED-CASE, CLASSIFIED FOR USE IN SPECIFIED EQUIPMENT (DIXF)

GENERAL

This category covers Classified molded-case circuit breakers rated 15 to 50 A, 120/240 V maximum that have been investigated and found suitable for use in place of other Listed circuit breakers in specific Listed panelboards. The circuit breakers are Classified for use in specified panelboards in accordance with the details described on the circuit breaker or in the publication provided therewith. In addition, Classified molded-case circuit breakers may also be Listed with additional features such as a ground-fault trip element, ground-fault circuit interrupter, arc-fault circuit interrupter, secondary surge arrester, transient voltage surge suppressor, and the like.

PRODUCT MARKINGS

A circuit breaker that is Classified only is marked on the side with the statement:

??Classified for use only in specified panelboards where the available short-circuit current is 10 kA, 120/240 volts ac or less. Do not use in equipment connected to circuits having an available system short-circuit current in excess of 10 kA, 120/240 volts ac. For catalog numbers (or equivalent) of specified panelboards, refer to Publication No.______ provided with this circuit breaker. If additional information is necessary, contact [Classified circuit breaker manufacturer?s name].??

A circuit breaker that is both Classified and Listed is marked on the side with the statement:

??This circuit breaker is Listed for use in circuit breaker enclosures and panelboards intended and marked for its use. This circuit breaker is Classified for use, where the available short-circuit current is 10 kA, 120/240 V ac or less, in the compatible panelboards shown in Publication No. ______provided with this circuit breaker. When used as a Classified circuit breaker, do not use in equipment connected to circuits having an available system short-circuit current in excess of 10 kA, 120/240 V ac. If additional information is necessary, contact [Classified circuit breaker manufacturer?s name].??

The referenced publication is a compatibility list which tabulates the company name, catalog number, number of poles and electrical ratings of the Classified circuit breaker, in addition to the company name and catalog number of the applicable UL Listed panelboards, and corresponding UL Listed circuit breakers in place of which the Classified circuit breaker has been investigated. The compatibility list also details the maximum permissible voltage and maximum available short circuit current of the supply system to the panelboard. The Classified circuit breaker is not suitable for the specified application if the system supply characteristics exceed the maximum values indicated in the compatibility list.

One copy of the compatibility list is provided with each circuit breaker. Circuit breakers which are both Classified and Listed have markings as above, with the addition of the Listing Mark, located on the side of the circuit breaker.

RELATED PRODUCTS

For information on markings, see Molded-case Circuit Breakers and Circuit Breaker Enclosures (DIVQ) and Circuit Breakers (DHJR). For those Classified molded-case circuit breakers containing additional features, refer to the following categories: for Arc Fault Circuit Interrupters, Branch/Feeder Type, see AVZQ; for Circuit Breaker and Secondary Surge Arresters, see DIMV; for Circuit Breaker and Transient Voltage Surge Suppressors, see DIPJ; for Circuit Breakers with Equipment Ground Fault Protection, see DIYA; for Circuit Breaker and Ground-fault Circuit Interrupters, see DKUY.

ADDITIONAL INFORMATION

For additional information, see Circuit Breakers (DHJR) and Electrical Equipment for Use in Ordinary Locations (AALZ).

REQUIREMENTS

The basic standards used to investigate products in this category are UL 489, ??Molded-Case Circuit Breakers, Molded-Case Switches and Circuit Breaker Enclosures?? and UL 67, ??Panelboards.??

LOOK FOR CLASSIFICATION MARK ON PRODUCT

The Classification Mark of Underwriters Laboratories Inc. on the product is the only method provided by UL to identify products manufactured under its Classification and Follow-Up Service. The Classification Mark appears on the side of the circuit breaker and consists of the words ??Underwriters Laboratories Inc. Classified Circuit Breaker?? together with a control number. The words ??Underwriters Laboratories Inc.?? may be abbreviated ??Underwriters Lab. Inc.?? or ??Und. Lab. Inc.?? The following mark:(the mark would not cut and paste) appears on the front, visible surface of the circuit breaker.


--
Bob (AKA iwire)
ECN Discussion Forums
Mike Holt Code Forum
55

Originally Posted By: roconnor
This post was automatically imported from our archived forum.


I don’t know where anybody is getting that older AC cable without the bond strip (BX trade name) was never intended or used for grounding.


In 1959, the codes added the requirement for a bonding wire/strip on the AC cable specifically because some older cable using the casing as a ground would sometimes end up with higher than desirable resistance due to deterioration.

--
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

56

Originally Posted By: jmyers
This post was automatically imported from our archived forum.


Bob,


Have you ever seen the casing on the older BX cable glow? I would be willing to bet that many fine homes have burnt to the ground because of BX cable, especially from they adding insulation in the attic.

It is starting to sound more like you A$$ was busted by an inspector for putting breakers into a panel that were not manufacturer specific.

If that is the case, come on over to my house and we will play with different breakers to see if they indeed function as good or better than the originals. I have a Murray panel, with Siemens QP, Siemens QT and Murray MP-T style breakers. HE**, just for fun bring along any other breakers that you have which will fit. Bring your lunch we can make a day of it. Come to think of it bring some sparky friends so they know what they are talking about when they come across this.

I don't call mixed breakers and it has nothing to do with UL or the NEC. What I look for when I come across mixed breakers is that all of them have the same interrupter capacity rating as the main breaker. Beyond that, I would not know what to look for. I always just assumed that all breakers were created equal in function and performance (except, of course, those FP welding breakers).

One would also have to assume that all those breakers would have to follow a minimum standard from UL in order to be passed for use. Meaning no matter what the design or material a direct short of any breaker would have to be less than XX seconds.

I don't buy into the listed breakers on the panel theory, since the only one they are going to list are their own. They don't want you to replace them with other manufacturers breakers, it is money out of their pocket. That in my book would be like Volvo recommending replacing parts with Chevy brand, it just does not make good business sense.

Joe Myers

57

Originally Posted By: rpalac
This post was automatically imported from our archived forum.


Hi Joe,


Were not to Far from a difference in OPINION.


I take the same slant regarding breakers. I Have not bee busted, nor have I done the busting. I believe the stance you take is the same. I don't shoot down mixed breakers. I believe it's product design of minimum standars that has to be met. If you by a car you must use Ford parts not OEM bcause of warranty. However, that doesn't say it illegal or not acceptable. The manbufacturer doesn't like it cause he's not making the gravy.

As far as the BX, all materials have a failure rate under the right circumstances. I have never seen a case where BX has glowed. I have seen hot cables as well as hot conduit. I've seen bu bar melt becuase of an oxidized conection. It is a case by caser senario unless there is a specific design problem.

Humans make the errors, nature adds some help.

I might take you up on the afternooner, I live over here on Country Club, not to far from you. Sounds like the two of us will find a way to disagree but at least will get buzzed in the process.


Bob P.

58

Originally Posted By: roconnor
This post was automatically imported from our archived forum.


jremas wrote:
Do you really want me to disconnect it and get my Fluke out?

No ... just my curiosity thinking out loud. We wouldn't want you to end up like JO's "buddy" in the panel ... RIP ... ![icon_lol.gif](upload://zEgbBCXRskkCTwEux7Bi20ZySza.gif)

jmyers wrote:
Have you ever seen the casing on the older BX cable glow?

No, but I have seen deteriorated old style "BX" cable that looked like it would glow if there was a fault. I have also seen this with AC cable that had the bonding strip. I think it comes down to the condition.

--
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
59

Originally Posted By: roconnor
This post was automatically imported from our archived forum.


rpalac wrote:
... all materials have a failure rate under the right circumstances ... It is a case by caser senario unless there is a specific design problem.

Well put RP!

I still don't see where others are getting that old style AC ("BX") in good condition can not be used for grounding. Particularly since around 1960 model codes added the bonding strip requirement apparently to address deterioration issues when used for grounding. Some sparkies won't use it for [outlet] upgrades, but that seems more a liability concern in this lawsuit happy society.

AC cable (and more particularly old style "BX") was used in countless homes in my neck of the woods around NYC, and was actually required by local codes for these older homes. I am not aware of any widespread problems and it comes down to the condition. Take a look at Joe Farsetta's posts here, who is also from my neck of the woods.

I do think it's really important to check the condition and grounding path on these older cables (and any wiring for that matter). That can be checked out with ... ahem ... a SureTest. But I really don't get why HI's wont spend an extra 5$ or 10$ to get a better grade 3-bulb tester like the GB SureWire that will check that out ... ![icon_rolleyes.gif](upload://iqxt7ABYC2TEBomNkCmZARIrQr6.gif)

I am not saying that the old style AC ("BX") is not a concern ... just that it is not an automatic red flag in my book. You just need to be careful when ya run across that.

--
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
60

Originally Posted By: Bob Badger
This post was automatically imported from our archived forum.


roconnor wrote:

I still don't see where others are getting that old style AC ("BX") in good condition can not be used for grounding. Particularly since around 1960 model codes added the bonding strip requirement apparently to address deterioration issues when used for grounding. Some sparkies won't use it for upgrades, but thats more a liability concern in this lawsuit happy society.


I guess I am one of the others. ![icon_cool.gif](upload://oPnLkqdJc33Dyf2uA3TQwRkfhwd.gif)

Robert there is absolutely nothing in the NEC about determining the condition of a particular wiring method.

A wiring method is either listed in 250.118 as a grounding conductor or it is not a grounding conductor, period, no guessing at deterioration, no measuring for resistance.

I am getting that old style AC can not be used for grounding from the 2002 NEC.

It is not listed as a grounding conductor in 250.118 as it is not constructed as described in 320.100.

What is presently in use as a grounding conductor is fine as it was allowed when installed, but if I extend the existing circuit or change 2 wire devices to 3 wire devices I now run into trouble with NEC 80.9(C) or for me in my state MA rule 3.

Part of 80.9(C)
Quote:
Electrical wiring added to an existing service, feeder, or branch circuit shall not result in an installation that violates the provisions of the Code in force at the time the additions are made.


MA Rule 3
Quote:
Rule 3. Additions or modifications to an existing installation shall be made in accordance with this Code without bringing the remaining part of the installation into compliance with the requirements of this Code. The installation shall not create a violation of this Code, nor shall it increase the magnitude of an existing violation.


I am sure you have seen old NM cable with a reduced size grounding conductor.

I could not extend that circuit using the reduced size grounding conductor as it does not meet code today.

I in no way mean to say what is existing is non compliant, the problem comes when you want to extend or change the use of the old circuits.

--
Bob (AKA iwire)
ECN Discussion Forums
Mike Holt Code Forum