| Author | Message | ||
| Jim Shepherd (Rv_Safetyman) (67.234.203.57)
Rating: N/A |
Well, here we go again on the often heated subject: marine cable vs. romex. The two main arguments against marine cable is that is does not comply with NEC and that you have to use crimp-on ends to terminate under screws. As I recall the issue with the NEC is that the cable is not UL listed. I just discovered that the marine cable that I have been using is UL 1426 listed: https://www.delcity.net/tstore/servlet/pagebuilder?frame=catalog_browse&parentid=356&page=1&childid=181037&pageitem=1 I do not have any financial connection with the vendor: Del City. I find that they have good prices and it is easy to order from them. Back to the argument. If my understanding of the issue is correct, since this marine wire is UL listed, it will comply with NEC and can be used without fear of insurance issues. The issue of termination is still there, but using professional grade crimp-on terminals just makes good sense anyway. Let the fun begin! Jim Shepherd Evergreen, CO ’85 Eagle 10 Bus Project details: http://www.rvsafetysystems.com/busproject.htm | ||
| George Myers (12.74.75.54)
Rating: N/A |
To be NEC approved, it must be of a type that is NEC approved AND the specific brand must be UL listed. Specifically, the wire Types (actually called "cables and raceways") that are approved are those described in Articles 320, 322, 330 through 340, 342 through 362, 386, and 388 of the NEC. That is a lot of choices, but boat cable is not one of them. I used conduit, but Type-MC, usually called BX, would probably work better for most coach builders. | ||
| FAST FRED (65.154.177.40) Rating: N/A |
Following the house code was taken as the lowest common demonator by the self serving RVIA rules, seems not to cause many fires.Even when "installed" by minimum wage help. Unquestionably house junk/systems has burned down coaches , just ask DML. However since most individuals are NOT in the business of Mfg cheap trailers for resale , the "Code Aproval " is a non starter, using the BEST that is avilable (within reason) works fine. Custom Coach used to simply drop boat wire into a chanel on the light valence, and it never had burn downs. Of course they used DC not AC switches and were only interested in rapid assembly , not sub standard low cost parts. Since the house code is completly unaceptable in any moving vehicle every where in the US and world (cept for the self serving RVIA) the use of wiring and equippment designed for vehicles seems a better prospect. Aircraft do a great job , but too much is traded away for light weight , esp in the toxics that come from overheated wiring (just ask Swiss Air that splashed in to Peggys Cove . Submarine/Navy wire is better but few have a source , of the required wire and terminal sets. And few campers worry of EMP blasts harming their readyness. That leaves auto or boat wire. The auto stuff is avilable Ez enough , but the lack of any tinning , and the use of coarse , rather than fine wire could mean problems from vibration if a less than "perfect " instalation is made.Same as romex. The winner is a high quality of boat wire. Anchor brand is 15% oversized , and with THEIR fancy ($$$) crimp end tools and the proper terminal ends , fine connections can be done by an amateur. Some basics need to be followed in terms of supporting the wiring , minimum bend radius. There are also gromets or fairleads needed each time a wire goes thru anything .All very simple to use , and really great fusing for 24/24V heavy loads ,(inverters ) and controll/ safty circuit breaker panels are made that are much more suitable for camper service than huge house boxes , that require loads of space for amateur hookups. If the CB is simply used to protect the circuit and a properly sized fuse is at the appliance , that's about all you can do , with out newly created arc fault CB made for aircraft (big $$$). While "Bestitis" is certainly a disease to be avoided in most design selections , the use of what ever wiring has the BEST chance of keeping you and your family alive does , Works for me! FAST FRED | ||
| George Myers (12.74.64.141)
Rating: N/A |
Dear Fred, Per your statement "Unquestionably house junk/systems has burned down coaches , just ask DML." My understading is that DLM burned because of a failure in a heater, not in the wire feeding it. I was on the road at the time this was getting sorted out. Would you please provide a copy of the information you have showing that it was the wire not the heater. Since fires caused by wiring that is done to the NEC standards in coaches is so common (per your statement), there should be a lot information on the web about them. If this is true, I think everyone would like to see it. I could not find anything. Because almost all commercial RVs are wired to NEC standards, there should be many sites with the gory details of these fires if your analysis is correct, so don't limit your self to just coaches. I'm sure everyone wants to see this information. George Myers | ||
| comp1880 (68.243.70.100) Rating: N/A |
http://search.yahoo.com/search?fr=slv1-&ei=UTF-8&p=rv+fires+caused+by+wiring | ||
| Randall Hays (69.4.194.50)
Rating: N/A |
Hello folks, I went to the page listed above and found that they also have a RVI section and all the wires are UL listed. The RVI section also has a better selection of sizes and colors than the Marine section. By the way what happend to going to your local Electric supply house and buying the correct wire? | ||
| BrianMCI96A3 (65.40.150.96) Rating: N/A |
Hmmmm, I find that particular link interesting in that 4 out of the top ten articles stated listed 12V DC wiring as the cause of most RV electrical fires. I also did a couple of searches using ...coach"electrical fire" In ten pages of articles no OTR coach fires were mentioned, although three train coach fires started by battery box wiring were. And ...Bus "electrical fire" A handful of fires mentioned in 10 pages of articles, described as "small" "Bus rebuilt by manufacturer" "confined to engine compartment" etc, etc. Brian | ||
| BrianMCI96A3 (65.40.150.96) Rating: N/A |
Personally, I will not be using romex, I intend to find a suitable fine strand wire of the appopriate gauge utilizing flexible conduit (I think sealtite is the name) throughout. Brian | ||
| ChuckMC9 (Chucks) (64.105.16.108)
Rating: N/A |
This is only slightly tangential to this topic about a recent fire in a stick/staples, cause unknown at this point.  http://irv2.infopop.cc/6/ubb.x?a=tpc&s=8076099152&f=9686094452&m=8716013865&r=7696004865#7696004865 | ||
| BrianMCI96A3 (65.40.150.96) Rating: N/A |
Tangental, or not, depends on what caused the fire in the stick & staple. I mean, what if it was arson? Brian | ||
| Gary Carter (68.25.127.95) Rating: N/A |
Also contrary to what some are saying there is NO difference between an AC and a DC swith. The are both just contacts. You do need to be concerned that the switch will carry the amps needed and it is rated for enough voltage to keep arcing down. If it is to be used in a high current system an arc suppresion diode would save the life of the points in the switch. Shuting off a DC circuit does create a great deal of back emf (remember how ignition coils work in you car). | ||
| FAST FRED (63.234.22.244) Rating: N/A |
The guts of most AC or DC switches is indeed different.A hacksaw will show the difference. Perhaps to open 3A its no big deal , but to open 40A it does require the rated DC type , to do it very often. Any switch used in any RV circuit should have its AC and DC rating cast or stenciled onto the side. No rating , find a better grade switch. The marine folks and the off grid folks all sell rated AC & DC switches. I would assume that most DC fires would be caused by the cost of type T fuses & the holders for them. The T will break a dead short in an inverter feed line , that can run thousands of amps , for a short time. And is the ONLY way that seems reliable to protect such circuits , according to Home Power , who has been doing this for a few decades. On the DML "loss" ,I have no idea if the wiring was poor , the unit had no safty's , or no overheat switch , no fuse at the appliance or a convient rag began the blaze. There is no question RV's do burn , and electrical fires do happen. If there was a huge problem with junk wiring the Liars for Hire , would be there collecting millions . Same with Propane , its a great fear for unexperienced folks that have never lived with the pure convience of silent heat & refrigeration, but not a terror , as the lack of News Flashes show. As an "Author" George MUST parrot the line "follow the code" , as some fool could decide to own his life after reading an article & suffereing some imagined "loss". I'm just one guy that enjoys living as easily/safely as I can , and have no fears I'll be suied for my skivvies by a rapacious Trial Liar barrister, for having an OPINION! as always , Do it YOUR WAY,(and don't wake up dead) FAST FRED | ||
| jc (65.67.220.55)
Rating: N/A |
I think we all want to enjoy living easily and safely, but when someone yells "fire" and can't back it up, we all lose. I also seriously doubt that being an "author" eliminates George's right to tell it like it is. I respect your opinions, Fred, and enjoy your insight, but I have to go with George on this one "where's the beef?" | ||
| George Myers (12.74.75.214)
Rating: N/A |
Dear Fred YOU DID IT AGAIN!!!!! Your emphatic statement in the post above that I only hold the position I do because I am afraid of being sued is far from the first time that you have attacked me on the boards without any basis is fact. Clearly the comment is made as if it were a statement of know fact, not your wild idea. The only way you could actually "know this" would be if I told you (which I didn't) or if you have extra sensory perception. Do you have ESP???? Prove it. George Myers TO EVERYONE ELSE; My apologies for putting this crap on the board. As an Electrical Engineer I am very concerned for electrical safety. Wiring for 120 volts is not a children's game. Letting comments stand that ridicule established safety practices could get someone killed. The reason I support the code is because it is proven technology based on actual experience and testing, not gut feelings. | ||
| FAST FRED (65.154.176.211) Rating: N/A |
However fine you feel about touting the code is very nice , we have all read the same article about 200 times in BC, but I feel obliged to point out it is a HOUSE CODE , and no moving thing in the world besides RVIA uses such concepts in any vehicle anywhere. Even Chinese generators don't use solid wire bent under screw terminals ! As a "trained " engineer you of all people should be able to understand what vibration and dynamic loading does to solid wiring. It doesnt take a Mind Reader to understand how mooving SOLID copper crysatalizes and then FAILS. Enjoy your house romex , I prefer Marine Wiring that WAS created for severe service in a hostile mooving enviroment, As they say , Do what let's you sleep at night, I do,, I certainly will visit next Jacks party and look at your skoolie wiring and see what 400A of inverter power supply looks like in UL style house cable and fuses! An Education for sure! FAST FRED | ||
| comp1880 (68.243.138.37) Rating: N/A |
Bravo Bravo encore encore | ||
| Sam Sperbeck (204.248.119.254) Rating: N/A |
Hi Fred, It is obvious to me that you have never read the National Electric Code. If you had you would realize that it is not just a "house code". Section 550 of the NEC pertains to RVs and RV parks, and other sectons pertain to commercial, industrial, and, yes, even homes. There are many types of wire and wiring methods that are approved for RVs, not just romex. Please read the code book, available at your local electrical or building inspectors office, or many libraries. I doubt that it will change your "OPINION" about "boat wire", but, maybe you will be a little more tolerant of those of us who choose to follow the NEC. Or, is "YOUR WAY" the "ONLY WAY? Hi comp1880, Who are you "Bravo Bravo encore encore"ing, Fred or George? Thanks, Sam Sperbeck La Crescent, MN | ||
| R.C.Bishop (128.123.221.219)
Rating: N/A |
Now, Boys....an opinion is still an opinion....Websters lastest ( that I have) defines it as " a belief that is stronger than impression and less strong than positive knowledge"...."a judgement"....and, alas, " a formal statement by an expert after careful study" Who's to know? Opinions abound in politics, day to day living, in spiritual beliefs and best food to eat ( or not) . Does that make anyone absolutely wrong? Or absolutely right? Doubt it. I've always heard experience is the best teacher.\\ So what's wrong with "works for me"....  Opinions provoke thought, which produces ideas, which produce results, which produce ?????? Know what I mean? How can anyone be all wrong....or all right? Lots'a good stuff here on this great board. Thanx to ALL! Keep it comin'. RCB '64 Crown Supercoach (HWC) | ||
| Jayjay (152.163.252.163) Rating: N/A |
DC rated switches have much larger and harder contact faces, and far stronger springs, than AC switches, to create a faster "snap" action of the switch mechanism. Arcing is much worse in DC circuits, and an AC rated switch will occasionally not move fast enough, or have enough "gap" to even break a DC load. Under heavy amperage loading an AC switch will continue to "arc-across" and not shut off the load! That's part of the reason a DC rated switch is much more expensive than it's AC counterpart. You can look up the specifications for construction and use for the pair in The Americal Electrician's Hadbook. (An engineering/application treatsie,)About 1500 pages, and $165.00, so try the local library. Also: Electical Engineering Practices; (VanValkenberg,Nooger,and Neville; Simon&Schuster-now out of print-again, try the library)Also: Principles and Practices of Electrical Wiring Systems; National Fire Protection Ass'n. (NFPA/NEC) [What's wrong with "works for me"]? Plenty is wrong with it...laws and safety codes are written to protect you and I, from individuals who use substandard materials, and poor installation practices, just because of their "it works for me" attitude. I have no sympathy for the person who violates those laws, and then gets fined or sued, due to his negligence. Just remember that building codes are DIFINITIVE laws, in that they tell you what you MUST or SHALL do!!! You have no recourse to OPTIONAL materials or methods...you can only do/use what the Code states. This is contrary to our daily lives, where a law says you can't do something, so by default you can do it any other way. Codes aren't like that. When you follow the Codes (all of them) you can rest assured that every provision in it has been through many legal challenges as to it validity of purpose, and you will have a SAFE, secure, saleable, legally defensible coach. One you can drift off to sleep in, and be secure in the knowledge that it won't collapse around you, drown you, or toast you! Cheers...JJ | ||
| FAST FRED (65.154.177.81) Rating: N/A |
"You have no recourse to OPTIONAL materials or methods" There would seem to be loads of criminals in the RV business , as I'm yet to see the orig factory wiring on a new RV chasis ripped out and replaced with RVIA/ UL approved like solid romex. Wouldn,t the need be for a Complete "house code" in every part of the RV , not just what the converters slap together? Wondering. FAST FRED | ||
| Doug Dickinson (Dougd470) (65.161.188.11)
Rating: N/A |
Fred It is getting obvious to me that you either did not read the NEC, or have forgotten what it said. While I agree that marine wire is an interesting idea, it just doesn't meet code. I suspect there is a reason. You may or may not like it. (BTW - romex is not allowed for 12VDC chassis wire - the NEC will tell you that. Doug St Louis MC9 | ||
| Tim Brandt (Timb) (12.8.192.60)
Rating: N/A |
Heated points of view asside can anyone quantify why pretinned, fine strand marine wire does not meet whatever code???? The reason I ask is that I have installed many marine systems in boats I have lived fulltime on and they are very robust by necesity. From a code and insurance perspective I can also attest to the need for them to be done to a set code verified by a complete survey of the vessel to attain insurance. Again please don't misread this as a rant of any kind I am just asking for an explanation since I know from a safety perspective there a very specific reasons marine spec wire etc is used on a boat and would like to know what the difference would be for a land yacht. Respectfully, Tim | ||
| Doug Dickinson (Dougd470) (65.161.188.11)
Rating: N/A |
Tim In the marine electrical business, the type of wire and methods used are dictated by the DOT (Coast Guard) the NMEA as a manufacturers group, and others. The DOT acts as a code enforcement entity in several respects for commercial and commerce functions as well as pleassureboat use. I am not as familiar with the marine side as I am with the NEC function as I haven't been involved in boats to any major extent in over 25 years. The marine "codes" are well thought out, well planned, and very safe for their application. The process of having a survey performed further validates the process used in the marine industry. I don't doubt that marine wiring will work well in an RV environment - in fact, my personal hunch, based on many years of vehicular experience, like cars and trucks, is that the marine methods are probably very superior in a vehicular application. The only and very simple point I am trying to put forth is that the marinewire is not in the NEC as an approved wire type (and some other issues). Even if they are UL accepted, it does not make it an NEC approved type. Remember - there are different types of wire in the NEC for RV use than "romex" style. The NEC is not perfect, and sometimes it may not make a lot of sense, but it is the best thing we have. If someone were to propose marine wiring, it might even be approved. My contacts say that this has not been brought up for consideration in the NEC. As an NFPA member, I may just suggest that for the next go-around on the code. If nothing, we may get an answer on your question. One other point - As others have said, there may be better ways, but in a fire or other major loss, you can bet your insurance carrier will be looking for ways to opt out of paying (at least some of them do) and using non-code wire and methods are certainly one way they will look at the issue. If you sell your coach, you could still be on the hook for a fire. And as always, we have the option of doing it our own way in our own coach - no matter what the consensus here is. Doug St Louis MC9 | ||
| Tim Brandt (Timb) (12.8.192.60)
Rating: N/A |
Doug, Many thanks for the clear answer. I understand you weren't taking the position that it is an inferior product I was just wondering if it had been excluded from the NEC for a specific reason. Perhaps as you mention they may consider it for future inclusion. From a personal perspective I had planned to use the same systems I was familiar with and had come to rely on 100 miles offshore but not wanting to be blind to other considerations wanted to know if there was a reason it shouldn't be used. Again thanks, Tim | ||
| Nick Morris (Nick3751) (65.117.139.135)
Rating: N/A |
I think we can add another topic to the list that you don't talk about among friends if you want to keep them: Politics, religion, and RV wire!!!!!! | ||
| Doug Dickinson (Dougd470) (65.161.188.11)
Rating: N/A |
Yup! Quite an emotional subject! Tim - you have a good point. You are familiar with the techniques and the methods, where many here are not. I know I would want a little training before I jumped back into something I am so far removed from for many years. Keep us posted! Doug St Louis MC9 | ||
| Tim Brandt (Timb) (12.8.192.60)
Rating: N/A |
Will do Doug. I'm at the hardest part right now finding....the right shell. Scratch that....2nd hardest part, the hardest was convincing my wife it was time for another project after selling our last boat | ||
| Telestar Emery (142.59.209.189)
Rating: N/A |
HellO Friends, One of the reasons you don't find the mention of Marine application wire in the NEC, is mainly due to cost efectiveness. When something will do and is safe, cost factor becomes a factor. Marine grade wire (and I don,t mean 12V) is far superior to any kind of house wire be it romex or whatever. The Maine wire is made to withstand the everchanging environment (especially moist) and is allso configured to withstand vibration at a much higher level. You won't find house wire in a ship or a factory built houseboat. FWIW My $02 | ||
| Nick Morris (Nick3751) (65.117.139.135)
Rating: N/A |
Ok let me see if I've got this right. The issues that all these disscusions center around is stranded wire is harder to put ends on to attach under a screw. It also does not comply with the NEC (which I think is up in the air at this point). As for romex the issue is that it doesn't hold up well to vibrations in a coach that is amplified by a possible cut in the wire due to striping insulation. Also those against romex state that it is harder to run than stranded, that I don't think is in dispute. So does that pretty much cover the core of the argument. The purpose for the inquiry is that I hope I'm not too far from begining to wire my coach and I'd like to understand the ins and outs of this issue. At this point I'm leaning towards using some type of stranded wire and I'm also planning on purchasing racheting type crimping pliers. Ya'll don't slam me too hard here I've done some wiring before in barns and a little in a few houses. I took a few wiring classes in college and scored at the top of the class which I know doesn't qulify me to wire houses of busses but nothings caught fire yet so I must not be doing too much wrong. Anyhow thanks in advance for the input. | ||
| Jayjay (64.12.116.203) Rating: N/A |
Hi Tim...most types of marine wire have a rubber based insulation, as opposed to the thermoplastic type used in the rest of the world nowadays. This means it is far more prone to heat cracking and degradation by ozone. The situation is excaberated by the fact that the Coast Guard hasn't upgraded it's wiring standards in almost twenty years. NEC standards and practices are revised every few years (a total of 48 times since 1897). UL "listed" is much different than UL "approved", and just because a specific wire or cable is "listed" OR "approved" does NOT mean that it is acceptable in all uses or circumstances. Every provision in the NFPA/NEC Codes has been through at least one major legal challenge, (usually litigation involving a death) and a review by several committes of experts before it ever becomes force of law. None of it is frivolous, or ill concieved, nor is it a cop-out, and it GUARANTEES a very safe installation. One that is also legally defensible, when there is a serious injury or death. You're "liable" as the constructor...long after it has changed hands several times. If you follow the various Codes, (to the very beat of your ability) during construction, then you have a legally defensible position if involved in litigation later. If a plaintiff can prove "malicious intent" i.e. that you flagrantly and intentionally violated "Standards", then you can kiss a major portion of every cent you will ever earnng, goodbye. It's a sobering thought. Rhetoric, guessing, and table pounding will not change the fact that it is the law, and should be adhered to. As always, this has been an illuminating, and entertaining thread, and I want a copy of the schedule for the next installment in a few months!!! Cheers...JJ | ||
| R.C.Bishop (128.123.221.136)
Rating: N/A |
Hang on a minute......I doubt seriously that Marine "codes", or "doesn't meet the code" (NEC regulations)qualifies marine wire as "substandard".....and, as well, not necessarily "optional",but, in fact, may be superior to existing codes which have NOTHING to do with coaches, boats, ships, space vehicles etc. The fact that the NEC has not addressed the issue of motion use of electricity does not mean that one is in violation. Having been in the construction business for a few years, like 25 or so, as a sub and general contractor, all projects built to code and then some, I can tell you that the NEC leaves a lot to be desired for the " best " way of doing things in every instance, albeit one must comply, which in my experience means that one satisfies the minimum requirement of the code. For example and to simplify, if one uses Number 10 for a Number 12 requirement, I have never personally been cited as being in violation. Also, if one uses GFI outlets everywhere in the project, I have never heard of any violations being charged. If a hard wired smoke detector is used in each and every room, hall and space of a project, I have never known an electrical inspector to stop the project. Maybe overkill to the inspector, but to the owner, it maybe be the way it should be done... i.e. " works for me". I am in total agreement that the "code" is necessary and is good for it's intended use.... residential and commercial construction, but apply that same code to the NASA program and I would surmise they are way off the best approach.....not in theory perhaps, but in practical, day to day use. Seems to me that prudent is as prudent does. RCB | ||
| comp1880 (68.243.105.12) Rating: N/A |
Maybe the Marine code has always been superior and is the reason it hasn't had to be changed "48 times" in such a few years. | ||
| Jayjay (64.12.113.29) Rating: N/A |
Hi Tim...most types of marine wire have a rubber based insulation, as opposed to the thermoplastic type used in the rest of the world nowadays. This means it is far more prone to heat cracking and degradation by ozone. The situation is excaberated by the fact that the Coast Guard hasn't upgraded it's wiring standards in almost twenty years. NEC standards and practices are revised every few years (a total of 48 times since 1897). UL "listed" is much different than UL "approved", and just because a specific wire or cable is "listed" OR "approved" does NOT mean that it is acceptable in all uses or circumstances. Every provision in the NFPA/NEC Codes has been through at least one major legal challenge, (usually litigation involving a death) and a review by several committes of experts before it ever becomes force of law. None of it is frivolous, or ill concieved, nor is it a cop-out, and it GUARANTEES a very safe installation. One that is also legally defensible, when there is a serious injury or death. You're "liable" as the constructor...long after it has changed hands several times. If you follow the various Codes, (to the very beat of your ability) during construction, then you have a legally defensible position if involved in litigation later. If a plaintiff can prove "malicious intent" i.e. that you flagrantly and intentionally violated "Standards", then you can kiss a major portion of every cent you will ever earnng, goodbye. It's a sobering thought. Rhetoric, guessing, and table pounding will not change the fact that it is the law, and should be adhered to. As always, this has been an illuminating, and entertaining thread, and I want a copy of the schedule for the next installment in a few months!!! Cheers...JJ | ||
| FAST FRED (65.154.177.252) Rating: N/A |
If anyone wants more Emotional writing , just go to any Boat Board and read what the single engine folks say to the twin engine folks and vica versa. For a real Religious discussion read what Plow anchor fans tell Danforth style anchor fans , and visa versa. The point is these arguments verge on Religion , or Politics , not very likely to change any dieharts well reasoned position. Those that understand the dynamics of vehicles will make one choice. Those that live in more fear of some future B-rat than of electrical failure will take the other choice . Undecided? Take a real good look at marine wire , Anchor brand works great , and compare it to a chunk of romex. Attempt to install both in an electrical box , bend them ect , have fun. UL aproval is costly although far less so than marine USCG , so Anchor and other brands of the good stuff would never bother for house code approval as their product is far to expensive to burry in non vehicle walls. To hookup a dancing vibrating gen set to the coach the yellow Marine Power Cord 4 wire 6 gage is the greatest , and I have no idea how it could be done with any house wire made.. DO it your way , Danforth and single screw forever! MY WAY, FAST FRED | ||
| Doug Dickinson (Dougd470) (65.161.188.11)
Rating: N/A |
A couple of points: Fred, the gen set under NEC cannot be connected via solid wire. From the NEC: 551.30 (E) Generator Installations. Supply Conductors. The supply conductors from the engine generator to the first termination on the vehicle shall be of the stranded type and be installed in listed flexible conduit or listed liquidtight flexible conduit. The point of first termination shall be in one of the following: (it goes on from there). The wire that shipped with my Honda gen set for the coach is a very fine stranded wire in a pre-wired pigtail. The yellow cord may not be approved, but it will probably work. The operative word here is probably. Lawyers make a living defining words like "probably" and "reasonably". I prefer not to be the test case. Simple UL approval does not make a wire acceptable to the NEC - it has to be stated in the code by type to be acceptable (UL approval is usually also required IN ADDITION). Here are some physical aspects of wire that make simple house wire and methods undesirable for RVs. Copper that is not fully supported - meaning in a mobile situation is tied down securely - will flex. Stranded wire will move with less streching of the conductor when "rattling along in a coach" for lack of a better term. As solid wire flexes, it starts to "work harden" which makes the conductor brittle. It will eventially fail mechanically, but before then it creates a point of higher resistance and will fail because of electrical load. Stranded wire is more forgiving since the relative motion of the strand diameter is so small that it is not streching when it moves (comparitively speaking) and far less likely to fail. Marine cable also has somewhat different insulation standards and is frequently "tinned" which creates a protective layer against corosion (actually a sacrificial layer when you get down to it). Now - there are some differences which bear discussion from a technical persoective. Insulation for instance is different as thermoplastic (most types) are not as good in moist and corrosive environments as rubber based compounds. On the other hand, rubber decays faster than thermoplastics in dry or fluctuating temps (due to drying). Undersea cables are still insulated with a form of rubber as the primary water barrier from the conductor. Salt makes the formula more interesting and involved. Now - does that make marine wire substandard? Nope! It is just different. Incidently, cost is usually NOT a big factor when considering inclusion in the NEC. The committee that deals with the code is driven by safety - and cost becomes quite secondary to their mission - despite what some say. Remember $125 GFI breakers for the house? It's all market based! I have to agree with Fred on one point, which I think we need to keep in perspective as we deliberate this issue and that is that this is like religeon - everyone has a strong opinion and absolute physical proof is fleeting. The anchor analogy is very true - that is a huge point of discussion in maritime worlds. Now for a personal perspective that I think will shape "my way". I am spray foaming the interior after wiring. I will be using armored cable (steel flex outer jacket) due to the action of the foam on many types of plastic. I do not want a wire failure point to be touching the foam due to combustability (No, I don't have the money to put NASA gade foam in the coach). The wire that I use in the flex will be either TW (solid copper) or THHN (stranded but large strands) or something similar. The armour flex will contain the wire from any significant flexing since the flex will be contained in the foam for the most part. So - that's "My Way" Doug St Louis MC9 | ||
| George Myers (12.74.74.228)
Rating: N/A |
The idea of a solid wire fatiguing and failing has been a boogie man that The-sky-is-falling members of our community have used for years to frighten the newbees. The reality is that at least 95 percent of the RVs on the road use Romex cable. Formally called Type-NM, it has three single strand (solid) conductors in a plastic jacket. I have made a ten-year quest to find out how many RVs have had a failure due to the solid conductor wire fatiguing. The conclusion of my search is that the solid conductors simply are not a problem. I have asked fellow RVers on the CompuServe RV forum, bus conversion bulletin boards, Escapees technical board, and many individual RV owners if they ever had a fatigue failure. Not until Busin 2003 did I find a single case of anyone saying that they had actually seen a wire that fatigued and failed in an RV. In that case, the break occurred at an outlet that was not installed in a box, and the wiring showed other signs of poor workmanship that could have been the cause of most of the fatigue. That is just one failure that I could find in all of the RV industry for all time. I have had people tell me they had a circuit go dead, so it must have been a failure in the Romex, but they had not actually found the break. This is an important issue that I think needs to be put to rest. As I asked above, if there is any documentation of actual problems, please share it with the rest of us. Otherwise lets end this nonsense. | ||
| Tony (64.215.196.112) Rating: N/A |
Amen George | ||
| R.C.Bishop (128.123.221.227)
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George, while I agree, generally, with what you wrote, I truly don't think this type discussion is "nonsense" when thoughts, ideas, concepts and, yes opinions are thoughtfully considered by the forum. How else did we arrive at the moon? Isn't that one major purpose of having such a medium as this? It is unbelievable what I have learned, read and mulled over the past few years that eminated from the BNO BBS. That doesn't seal in concrete my agreement or disagreement to any conclusions that I may draw, but it certainly does help in formulating a conclusion. Frankly, I wish we had more of this give and take, all with an eye toward learning something perhaps we, as individuals, had not considered previously. Unfortunate that a times a discussion gets ugly, but that usually straightens out pretty quick. I've always heard, and experienced, that there are many ways of skinning cats.....and maybe, just maybe, I had failed to find the best way. This board opens a lot of possibilities (food for thought) It's a great board Ian....Thanx much. And thanx to all for viable input. BTW, I am using THHN Stranded 12 gauge throughout, except where #10 or larger wire is called for. This run in Carlon conduit....or in a metal chase that is a structural part of the coach (and used for 40 years, apparently very successfully, with no wiring problems)FWIW RCB '64 CROWN Supercoach (HWC) | ||
| Sam Sperbeck (204.248.119.254) Rating: N/A |
Hi Fast Fred, I have often read that you think copper tubing is great for use as water lines in a bus. Why is it that solid copper tubing is good but solid copper wire is bad? Aren't they both subjected to the same vibration? Or, are you using "tinned and stranded, boat" copper tubing in your bus? Thanks, Sam Sperbeck La Crescent, MN | ||
| madbrit (67.136.87.158) Rating: N/A |
OUCH!!! | ||
| madbrit (67.136.87.158) Rating: N/A |
Perhaps if one uses the solid copper tubing as a conduit for the sold copper wire, would think it okay then? Peter. | ||
| Tim Brandt (Timb) (12.8.192.60)
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Lets not fan the flames by poking fun at Fred. We actually had a cival thoughtful converation going on. I for one apreciate the responses I have received. I do take to heart the legal issue even if I beleive Anchor wire to be a great product. So many systems in RV and boating are identicle (heart inverters for instance) and are acceptable in both that it's a good question to ask why the peice that connect the two systems together is different between the two. Not for a one is better than the other argument but simply for the pursuit of knowledge. My two lincolns. Ps Fred I have owned both single and double screw but both had a danforth. | ||
| Peter Broadribb (Madbrit) (67.136.87.158)
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Only funnin' I am sure FF realises that, but I still like Romex. However, interesting point you bring up about the inverters, etc being the same and only the wire is different. This compatibility problem exists all over the world. We had American cars coming into England which complied to the same construction standards of testing, but because the auto companies didn't get the various standards of Europe and the USA certified as being the same or similar enough, we had an awful job importing cars at one time, until they allowed personal imports. Tyhe new ones which came through dealers had to have ugly trailer light units screwed over the stock rear lights. Good job they didn't insist upon changing all the glass. However, that said, a buddy of mine tried to import a Mustang II from Belgium and because it had American glass, etc. and the fact that the car was actually available from the English dealership, he was told he had to change all the lights and all the glass to "E" marked and certified items. How stupid things can get. Peter. | ||
| FAST FRED (65.150.247.97) Rating: N/A |
Due to the diameter of most copper tubing it doesn't get bent around corners and when unsupported by a chase does a fine job of spaning the usually small RV distances between studs. Proper plumbing Mounting clamps to prevent movement are in HD and only a few cents each should there be a long unsupported run.. The end tubing fittings ARE usually properly attached , weather silver soldered on , or as I much prefer usung Flaired fittings. There is NO auto crimp ends equivilent for a water system. With solid wire bending it to go under a screw head will be most of what it takes to overbend & fatigue the wire. The advantages to copper water tubing are mostly health related , as green slime will grow in any plastic that gets enough light to it. Not only the clear stuff , the white water grade is NOT light proof and does grow science experiments. PEX and other "Quickie" stuff has had law suits for failing since its invention, I have better things to do than fix junque, although the small boat marine industry loves the stuff. MY preference for Flaired refrigeration (dead soft) tubing is a maint item. Its far easier to simply replace any section of flaired tubing than soldered together tubing in most built coaches. A lazy fool can break the tubing by not properly winterizing , but at least he will be a healthy lazy fool! Works for ME! FAST FRED | ||
| Dan in NJ (216.254.91.50) Rating: N/A |
An item you might want to look at see RIDGID tools. (www.ridgid.com/tools/products) They have a new product called ProPress. Crimp connections for copper piping. 50 year warranty, can be installed in WET locations, etc. Have no connection to the company and have not seen it used yet. (I am in Commercial HVAC business as a Mfg Rep in NYC) Don't know if I will be able to rent it at HD or not, but it looks interesting. Just FYI. | ||
| Doug Dickinson (Dougd470) (65.161.188.11)
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George - I don't disagree with your assessment of the romex type wire being safe. I was pointing out how solid wire fails. It DOES take a lot (distance vs time) of movement of the wire, and wire is usually fairly well supported in the wall of a stick and staple or bus conversion RV. "My Way" is to do something maybe a little better than romex and stay within code. (Incidently, in houses, the failure point of wire is usually at the connector (switch or wire nut, etc), not along the wire itself unless damaged by a screw or nail). Fatigue of wire is unlikely unless unsupported. Same as for copper tubing. Given reasonable support in a conversion,I suspect this would be the leading failure point in an RV. If you want to see something interesting - take a wire that has been bent around a screw terminal and look at it under a microscope. How the wire "behaves" may be interesting for even the old-timers here. Try it with different wire types for interest such as soft drawn, some of the harder varieties of wire, and even stranded types. I saw the photos in a class I took some time back on arson investigation and it was interesting. Doug St Louis MC9 | ||
| Tim Brandt (Timb) (12.8.192.60)
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Peter, That is a good example and it's one that we Americans are just as guilty of. Just compare a series 1 and 2 E-type Jaguar. I can't stand the "federalized" tail lights that the US mandated.....big boxy things that hung under the bumper. Fortunately mine are the non federal version [IMG]http://members.tccoa.com/timb/jag2.jpg[/IMG] | ||
| ChuckMC9 (Chucks) (66.167.142.75)
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TIM! I had one just like that! '68 I believe it was, one year before those gloppy things below the bumper. Thanks for the reminder...  | ||
| ChuckMC9 (Chucks) (66.167.142.75)
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And in other completely unrelated news...  Fire gutted a Greyhound bus at Everett Station on Thursday, engulfing the front end after all 25 passengers had escaped safely. | ||
| Tim Brandt (Timb) (12.8.192.60)
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Chuck you are correct 1968 ser 1.5 2+2 I found it in a guys backyard in Stuart Florida with grass growing up around it. Bought it cheap and spent 3 years putting it back together. It's not a show car by any means but it is a good safe driver now. | ||
| Peter Broadribb (Madbrit) (67.136.96.46)
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"I am spray foaming the interior after wiring. I will be using armored cable (steel flex outer jacket) due to the action of the foam on many types of plastic. I do not want a wire failure point to be touching the foam due to combustability" Doug, I was not aware of any problems of foam attacking plastics or in your case it is the curing process that can cause the damage as you are spraying over the wiring? I was talking to the electic dept "expert" at my local HD, and he recommended using Romex buried in the Super Tuff-R foam board. This action would support the Romex too. Is this foam going to attack the outer sheathing of Romex too? Peter. | ||
| comp1880 (68.243.255.139) Rating: N/A |
Wow an expert that makes 8.00 per hour.. was talking to the electic dept "expert" at my local HD, and he recommended using Romex buried in the Super Tuff-R foam board. | ||
| Peter Broadribb (Madbrit) (67.136.87.66)
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Comp1880, I was rather hoping for some constructive comments on the possiblility of foam attacking the plastic wiring, not an attack on a person neither of us know, simply because he only earns $8 an hour. Peter. | ||
| R.C.Bishop (128.123.221.149)
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Madbrit..thanx for keeping the thread straight! Wish someone could supply the answer. Any CE's out there>>??? RCB '64 Crown Supercoach (HWC) | ||
| Doug Dickinson (Dougd470) (65.161.188.11)
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The foam that I am familiar with DOES have some affect on plastics when in the curing process. We used it in a fire station for after-the-fact insulation on a CBS structure inside. We had some class 2 wiring for sound and annunciator stuff that was imbedded in the foam. When we diasected the foam to get to the wire (for an addition), it was still functional, but the jacket was not in great shape, and getting all the foam off it was a job! Sticks like crazy. The actual cure process when the liquid turns into foam is actually a fairly violent reaction. The components individually don't cause much harm (depending on foam type), but the reaction is caustic and etches the surface of some plastics. When the reaction is complete, the result is fairly inert chemically. Will that cause the insulation to fail completely? I doubt it, but I don't even want to go there knowing that even some affect occurs. Another issue that you may want to consider is that of physical stress that the wire receives in a spray foam application. If the wire is routed too far from the walls, as the foam starts to harden, and is still expanding, the wire can be pushed around a good bit. The steel provides some protection in that situation and the wire itself can move to accomodate the foaming process affect on the flex. Now, the good side of all this is that you have supported a wire so much that it CAN'T move or flex. My concept - although it is a little overboard - is my attempt at "doing it a little better" than romex. BTW - I am not a chemical engineer - I am only passing along first hand observation. Even though spray foam has been used in housing with standard romex for years without any problems (that I know of), I saw some things that worried me - so - I am doing something that is stil code, but may be a better combination. "Your milage may vary" Doug St Louis MC9 | ||
| Peter Broadribb (Madbrit) (67.136.89.229)
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Doug, Thanks for straightening out what exactly happened. I had a feeling it was the curing process that was the cause. I was just thinking (Yeah, I know...) with all the talk about Romex needing support, that just pushing it into a small channel in the Super Tuff-R foam board, would provide all the support it could wish for. Does anyone know if burying the Romex in this foam is against code? Peter. | ||
| R.C.Bishop (128.123.221.215)
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Seems to me one of the problems with burying any wire, stranded or solid, without first running thru conduit opens a great possibility of fasteners penetrating the wiring....and since most bus frames are considerbly less than 3.5 inches in depth, before any finished surface is even considered, "code" is not followed under any circumstance. In adobe construction, the code requires a plate to be put over the wire run where the wire is not buried 2.5 inches ( as I recall) in depth. Likewise in standard construction, wire is to be run buried halfway the thickness of the framing member. (again, as I recall....haven't done it for a while so haven't checked for any changes) The alternative that seems to make the most sense is running all wire thru a chase at floor, under window, or ceiling level (at the junction of the wall) ... i.e , a dadoed base board or trim board. Then fastners and obstruction are never a concern. In our case we have used all three methods. NO wires buried and easily accessable. "works for us"... RCB '64 Crown Supercoach (HWC) | ||
| Peter Broadribb (Madbrit) (67.136.89.229)
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RCB, The construction of the body is as follows: Aluminum outer skin, riveted top and bottom with "Z" section ribs every 16" on center. This gives me a place to slide a 1" thick panel of Tuff-R behind the lip of the "Z" rib and it will push in against the next one. I am then covering the whole wall with another 1/2" of Tuff-R which will give me about R-11 plus whatever little I get from the plywood. This is as good or better than some mobile homes or block built homes have so I am happy with this. I can't go thicker due to the windows I have are for a 2" wall. I could hide the Romex in the "Z" section, BUT that is where someone will try to screw something into at a later date, awnings, lighting, etc. At this time, I was considering running the Romex through the basement storage and up the wall inside some sort of steel conduit. But I just pulled a cabinet from my old Apollo and found they use seperate wires in a steel flexible conduit. This means I can buy a multi-stranded wire and run 3 of them through steel conduit and cover all the bases........ I hope..... LOL. Peter. | ||
| Scott Whitney (66.82.9.42) Rating: N/A |
You can also buy rolls of THHN stranded wire in green, black and white and run it in bundles inside a blue corrugated plastic conduit that is very easy to work with and goes around corners. If I were to wire another bus, I'd go with the above method or boat cable or some mix of the two. | ||
| R.C.Bishop (128.123.221.227)
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Madbrit/Scott Crowns ( ours at least) are built a bit differently....on a regular chassis frame, with flooring attached at top of frame. Therefore, it is easier (more prudent) to run all systems within the coach. And that is fine with me. We also run all water and sewer lines within the coach. Most stuff is mounted on the driver side wall, front to back, on the face of 1/2 inch plywood. We have bays, but they are "boxes" welded to the frame on the lower side. The largest bay is a "trunk", at the rear of the coach and behind the frame. One could easily put a double bed in that space which was used originaly to carry the luggage and freight. The conduit we used is rigid, but is approved, Carlon by brand, and has many different fittings , bends, etc available. HD, Lowes, etc., or your local electrical supply house carries it. I considered flex tubing, but felt that fasteners would penetrate the kind I saw. AC is separated from House DC ( all 12 Ga THHN Stranded and crimped terminals for the most part ) in two separate conduit runs, both at floor level, one mounted above the other and each marked at every outlet or switching location. These "hidden" behind a base board. We also have a chair rail with two chase runs for possible added wiring down the line. Nice trim board with no evidence of anything like wires. Most 12V (and communication cable) for minimal coach lighting, (off the starting batteries) is run thru two existing large metal chase runs, ( the length of the bus, on both sides) and are controlled at the driver area. The inverter also runs off the two 8HD's at this time. That will be changed, of course when house batteries are added. Except for behind the shower, where the plastic conduit is run under the plywood, all conduit is "exposed", but hidden. We insulated like you did, but added a layer of bubble foil between ply and frame members, top and sides. Final finish is 1/8th oak ply over 1/2 inch ply. This has been an interesting thread and I am not sure anything has really been resolved, but lots of ideas for those who have that to yet accomplish. I have hashed and rehashed this over a couple of years and thanx to those who contributed, including George Myers book, I came to the above conclusion on just how WE would proceed. So far, .....so good, as the saying goes. Thanx for the input. RCB |