Douglas Hansen

This is the first time I've seen 25-amp FPE breakers. This whole installation looks like a hall of fame candidate. I'm fairly confident that the power is coming in to the black cable at the top of the fuse panel, and I am mystified by rest of it. Can it be that the other three cables exiting the top of the fuse panel are all 240-volt? It looks that way, but ????

Our security folks have finally come out with a way to view the book on an iPad. It is a web view that requires an internet connection, whereas the ebook for MAC or PC only requires a connection to download, not to view after initial registration. It does seem to have full functionality. Thanks

Since exposure to physical damage is not clearly defined, it seems that in some parts of the world inspectors are touchier about it than in other parts. Jim, in Maryland don't you folks routinely see it on basement walls? Looking at this photo of some fans in a basement, would it draw a correction notice in your part of the world? Around here, it would be written up as a violation of 334.15(A) & (B). Click to Enlarge 49.93 KB

It's funny how different things are from one part of the country to another. I did a seminar this last weekend in Reno and the inspectors there told me that they see nothing but cord-and-plug connections, despite the fact that the code prohibits it, and that UL has never listed a forced-air furnace with a cord-and-plug connection. Around here we see a few jack-leg installations with NM cable. Kurt's is relatively clean. Aside from the potential damage issue that Marc mentioned, usually the problem with NM is that it is not secured properly and that it is strung through the air, rather than following the building surfaces and framing. Kurt, it isn't NMC - it is just NM. NMC is a special type of cable used in barns and rated for corrosive environments. Look on pages 246-252 for more than you ever wanted to know about NM, and on page 251 for the skinny on NMC.

Reliance acquired FPE in 1979, and shortly afterwards discovered that "improper and deceptive practices" (their words) had been used by FPE to obtain their UL listings. Reliance divested FPE in 1986. The panels in your photo could not have been made after 1986, and could easily have sat for a year or so before going into that house. All FPE breakers had UL stickers, though they were often meaningless because of the cheathing FPE did to obtain them. Mark - look on page 151 of Electrical Inspection of Existing Dwellings.

Electronic version 2 was completed last night. If you have the first one, delete it and download the newest one. The print proof came back from the printer today, and the first orders ship on Tuesday. Click to Enlarge 52.29 KB

Layout is done and we are down to the final set of edits. Still missing a couple of key photos, so I may come here looking for help with them. Thanks

It is a (large) PDF. Unfortunately, the security program we are using renders PDFs inaccessible on iPads. They work on MACs or PCs, like the Code Check eBooks. If the iPad had a program that was truly an Adobe version of Reader or Acrobat then it would work there, but I don't think they do. We weren't able to do it on a test iPad using GoodReader. The book will eventually wind up in the Apple bookstore, though that is another licensing project, and will lag at least a couple of weeks behind the pdf version. If you are buying it primarily for the iPad, you might be better off with print. Thanks!

We are working our behinds off on this; it has turned into a much larger project than previously imagined. The electronic version might be available as early as Monday, and then it's off to the printer. We are cutting off the pre-sale (49.95) pricing this weekend, and then it will go to the full price (59.95 plus shipping). Mark and others - I really appreciate your advance order and your help here. This is a "crowd-funded" publication. I could not possibly have taken the time to work on it without advance orders. Thank you.

For a brief period of time (1931 - 1940) the NEC allowed up to 8 branch circuits to share a common neutral, on the wishful thinking that the load would be balanced. Though the permission to do this was dropped in 1940, it didn't become specifically prohibited until the 2011 NEC, in section 200.4, which says "Neutral conductors shall not be used for more than one branch circuit, for more than one multiwire branch circuit, or for more than one set of ungrounded feeder conductors unless specifically permitted elsewhere in this code." Even prior to 2011 it would be a code violation due to the conductors lacking adequate overcurrent protection. As Bob pointed out, the currents on the neutral that makes it home to the bus could be the sum of whichever phase has a load on it. Even if they upsized the neutral it would have parallel overcurrent protection and not be allowed by 240.8. All in all, just a fancy way of saying this is jackleg work. Why couldn't they just extend each one of these neutrals individually?

Mike - Thank you for posting this. I have been working day and night on this project since late September. The most time-consuming part is the extensive research into code histories for each significant item covered in the book. The price of 44.95 for the electronic version is 10% less than what the initial price will be when we begin delivery and shipment. The eBook and the print book will sell for 49.95 in January, and shipping will be charged on print purchases made then. The book is more than twice the size of the previous edition, which sold for 49.95. The eBook will enable readers to see the photos in color, and will have some search capability, though bookmarks will be the primary navigation tool. Unlike Code Check eBooks, it will not have links to the actual code sections. That only works for ICC codes, not the NEC. The printed book will have the photos in gray-scale, and they are all being painstakingly optimized in photoshop for the clearest possible reproduction. People who pre-order the electronic book will be given updates as they come along, and we will make some accommodation as well for folks for folks who pre-order in print (possibly addendums). I really appreciate the support of everyone who is pre-ordering it. You are the ?sponsors? of this endeavor. Thank you.

These breakers allow two branch circuits in the space that would only take on QO breaker. There may be a problem with this type of breaker not being listed for a class CTL panel. The side-by-side version that Square D makes today has a warning label on it that it can only be used in non-CTL assemblies. If the panel was completely full this could be a situation where they should have installed another panel instead of adding these.

Have any of them offered a reason for that one? Ground rods are copper-clad to prevent corrosion from contact with soil. Concrete, on the other hand, can be slightly corrosive to copper. Perhaps there is some concern about the soils down there creating a more aggressive chemical action. The original Ufer grounds were copper wires laid into foundation footings, and even today the NEC allows a concrete-encased electrode to consist of 20 feet of 4 AWG copper in the footings. They aren't going to show you a C&V on this from a national code.

In the old days, these problems would inspire unique solutions for each system. Today, the inverters that convert photovoltaic DC to AC are listed as "utility interactive." They need to see the signal from the utility and synchronize to its frequency. When it isn't there they shut down. There is no danger to the utility from a utility-interactive inverter. For the same reason, a backfed circuit breaker from a utility-interactive inverter does not require a locking mechanism to hold it in place. If you pulled it out of the panel, the breaker jaws would no longer be live; the inverter will shut down. With other backfed breakers, you would have a tiger by the tail. Very large arrays can cause issues with a utility because of increased short-circuit current. Small ones don't have that problem.

Section 90.2(B)&© of the NEC does indeed mean that electric utilities are exempt from the NEC. I'm sorry if you assume the implication of that statement is that they make up their own unsafe rules. It would be great if every utility behaved like yours or the ones described in Tom Raymond's post, but they don't. Here in California, our utilities are "regulated" by PUC orders 95 and 128, each hundreds of pages long, and each modeled on the NESC. They are widely ignored. Our local utility (sponsor of the San Bruno gas explosion) will not respond to a call for much less than their equipment being on fire. I have been through too many just plain ridiculous situations with them, including refusing to respond to broken service drop conductors. For a simple service update, they require a $2,000 deposit for "engineering services" which are nonexistent, and the process to recover the deposit (or what they are willing to part with) takes months. As far as the utility sizing conductors based on their anticipation of the customer's load, rather than the rating of the service equipment or disconnects, the worst I saw was an 800-amp 3-phase switchboard fed by 250kcmil aluminum. Equipment all through the facility was failing due to the voltage drop caused by the utility's undersized conductors. That was an example of them just making something up, and the customer taking it on the chin. Last year I inspected one where tens of thousands of dollars worth of equipment had been destroyed by water vapor because the utility forgot to seal their underground conduits. The facility was about 5 feet above the high tide line. The utility refuses to allow the contractor to seal them, insisting that only their own folks get to do that work. They take no responsibility when they subsequently forget to do it. I could go on but I think you get the idea. I know there are many utilities that do care about getting it right. I wish ours was one of them.

My favorite of late has been the phone call from "Microsoft" telling me that I have a virus. I usually just hang up, but one day they got me while I was driving so I decided to play along. They asked me if I was sitting in front of the computer, and I assured them I was. They proceeded to instruct me on how to go into MSCONFIG and a few other places to basically hand them control of the computer. After playing very dumb (not hard for me) and making them repeat every instruction a half dozen or so times, I did all I could to make them think they had really hooked a live one, then just hung up.

The size of the service drop conductors is not a problem. Here in the U.S., the utility is exempt from the NEC (per NEC 90.2C) and they are free to size their conductors based on anticipated load, not the rating of connected equipment. I don't know if it is the same up there. John will chime in with that answer. Conductors in free air also are allowed much higher ampacity than those in a raceway. Aluminum 2 AWG conductors are given an ampacity of 135 amps in table 310.17, though I think a case could be made for going straight to the 90 degree ampacity of 150 amps. My only Canadian Electrical Code is very old, yet seems to have similar numbers (only 140 amps though for 90 degree insulation).

There is no minimum bending radius for individual conductors, only for cable assemblies. There is a rule for the amount of space needed between the panel wall and the terminals. If the conductors exit the wall opposite the terminals, it is based on table 312.6(B) and assumes two bends will be needed in that space. If you look at the numbers in the table, it will work out to somewhere between 5 and 7 times the diameter of the cable most likely to be used in the lugs. You often see very sharp factory-made bends on service equipment. It isn't a problem. At low (<600) voltages, it isn't going to affect conductivity, strands of conductors aren't going to be stretched or damaged, and insulation will remain intact. Medium voltage cables with layers of dielectric insulation do have a minimum bending radius. House wiring doesn't. What matters is that the conductors lay into the lugs without adding stress to the connection. That is much easier to do if you make a loop rather than trying to run them the shortest distance. A proposal was made to add a minimum bending radius in the runup to the 1978 code. It received no support.

If you are talking about a bend in the individual conductors inside the panel, with no sheathing on them, that is how I would wire it. I prefer making that loop so there is something there in case the connections at the terminals ever need to be redone. 338.24 only applies to the cable with the sheathing in place. If what you are talking about still had the sheathing on it inside the panel, I would agree the electrician was a bit loopy.

Thanks Eric Clicking on your link it turns out even my local HD store has 28 of them in stock.

They are a specialty item, and probably cost more the $2 these days. I doubt they sell them in home improvement centers. I've only seen them in electrical supply houses. You can see the letters on the yoke and they are also embossed on the back. Click to Enlarge 28.63 KB Click to Enlarge 41.11 KB

Electrical components are tested and listed by "Nationally Recognized Testing Laboratories" (NRTLs). The most prominent NRTL is UL. NRTLs do not arbitrarily choose the manner in which components are tested. They are tested to published standards. For receptacles, the standard is ANSI/UL 498, and for snap switches it is ANSI/UL 20. CPSC is not a nationally recognized testing laboratory. The engineer who provided the bulk of "their" research on aluminum is not an electrical engineer. The test protocols which were followed for whatever research led to this CPSC statement have not been published, and there is no reason to imagine they were conducted in accordance with the procedures of the published standards. Per the NEC and the standards above, snap switches, and receptacles rated 20 amps or less, must be rated CO/ALR when directly connected by aluminum conductors. Other types of receptacles may be connected by pigtailing copper and using a suitable connector between the different materials. If you examine a CO/ALR receptacle or switch, you will see that the underside of the terminal screw head has a saw-tooth pattern designed to bite into the conductor and increase the area of surface contact between the materials. Of course they must also be applied at their proper torque setting (20 inch pounds).

We've updated the downloadable article on FPE at our web site. http://www.codecheck.com/cc/articles.html

A conductor should never loop around a screw in such a manner that the wire crosses over itself. If what you are talking about is placing a bend in the wire in such a manner that it resembles the letter omega then it is possible to go through the screw in the box or on the receptacle, though it isn't making things any easier for anyone. What's wrong with running a wire from the box and pigtailing the other equipment grounds to it?

The down conductors of lightning protection systems should be kept at least 6 feet away from metal parts of electrical equipment (like service masts) to prevent sideflash. The electrode for the lightning protection system is required to be bonded the grounding electrode system of the house power (NEC 250.106). What you saw is very similar to the bonding requirement we now have for CSST, and probably using the same logic. If the earth voltage is elevated, you want ALL the metal systems in the structure to rise to the same voltage - you don't want there to be a large potential between them within the structure. There's nothing wrong with the bond to the house side of the gas line. It sounds like the bond to the house power system might be what's missing.