Talk:Mineral-insulated copper-clad cable

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In what countries is this stuff used? --agr 03:48, 17 February 2006 (UTC)

You certainly see it in the uk mostly on older commercial/industrial installations and only very rarely on domestic installations. Its still afaict the best cable type availible in terms of fire resistance and it blends well with brickword/stonework but its just too costly for most installations. Dunno about anywhere else. Plugwash 12:32, 17 February 2006 (UTC)

The episode of grand designs where the bloke built his house out of straw certainly used copper sheathed cable, as to weather or not this was MIMS I cant say. He said he had to use it due to the fire hazard of running cable through straw bales, and to keep the mice from eating it. As for day to day uses its very well recommended for fire alarm installations, as well as the aforementioned industrial uses. Its not much use where it will be subject to vibration, but apart from that its pretty much everything proof.--Pypex 15:54, 23 February 2006 (UTC)

well i can't think of any other copper sheathed cable that it could have been. I suspect the main reason for doing it would be to prevent fires started by vermin damage (e.g. i think the two things mentioned are two parts of the same issue not two sperate issues). Plugwash 00:09, 24 February 2006 (UTC)

From the information I have seen above and having seen the episode of Grand Designs, I am also convinced that this was likely to be Pyro Mi cable. Pyro is still sold everyday into all manner of applications and the key benefits have been outlined in the article attached to this page. Commercial buildings remain the focus for most applications with fire survival being the critical factor for alarm systems, emergency lighting, smoke extraction systems etc. I would strongly agree with the comment above that states this type of cable is still the best for fire survival applications.

Contents 1 Eddy Currents 2 Fire-resistance and Explosion-resistance 3 Focus 4 Picture needed 5 Stonework 6 MIMS - drug prescribing guide 7 Changes to Alternatives § by anonymous user

[edit] Eddy Currents

Does MIMS suffer from the same problems with eddy currents when passing through steel enclosures or does the copper sheath prevent the conductors from inducing currents.?--Pypex 23:07, 2 April 2006 (UTC)

[edit] Fire-resistance and Explosion-resistance

I changed the suffixes "-proof" to "-resistant". You cannot say that it's immune to the effects of fire or explosions of sufficient intensity and duration. It's just not true. I wittnessed a fire test using this stuff at Underwriters' Laboratories of Canada, testing to the CAN4-S101 time/temperature curve and a couple of the cables failed the full scale fire test. Now, surely these were not "listed" subsequently, but it goes to show you the limits. The issues is and remains bounding. Even in a bounded configuration, if you have tested for three hours, you're still wrong to say that it's fireproof because you have no way of proving what would have happened one minute later, after you turned off the furnace. "Explosion-proof" is likewise quite a stretch. Explosions can and do cause flying debris, which can send projectiles of sufficient momentum to sever such a cable. If they can blow a hole in the side of a ship from an inflatable craft, rest assured, an MI cable CAN indeed be wrecked by explosions of sufficient force.--Achim 15:20, 31 July 2006 (UTC)

It's my understanding, and I don't claim to be an expert, that the term "Explosion-proof" does not refer to an ability to survive an explosion, which would seem impossible to assure, but to a requirement not to initiate one in an explosive atmosphere. e.g. by a spark. Also, I am curious: is MICC used in Canada? --agr 15:31, 31 July 2006 (UTC)

"Explosionproof" from an NEC or CEC point of view means that it cannot touch off an explosion. I've done hazardous area classification studies...which gives me some assurance that I know what I'm talking about. I would speculate that "fireproof" is applicable in the very pragmatic sense that once the building is burned down you don't much care if the wiring it left - if the MI is more fire-resistant than the structure, it's effectively fireproof. Yes, mineral insulated cable is used in Canada, the photo showing cables entering a panelboard was taken near Elbow, Saskatchewan at the Gardiner Dam. It tends to be rare in my experience since it's expensive to install and type "TECK" cable does most of what MI can do at a lot less cost (albeit with much less fire resistance).--Wtshymanski 23:50, 31 July 2006 (UTC)

"Fireproof" is indeed a faulty terms and the use of it would be indicative of the knowledge of the author. I did not know that "explosionproof" was a code-defined term in the electrical world. If so, I don't see why that would be applied to any cable. That is weird. An electrical appliance, OK, but a cable? That just seemed so unlikely. Even under full power, it would take an accident and a severing to cause sparks to fly etc. What makes it confusing is that there is a whole world of explosion-resistant products, which would be referred to as explosionproof by novices, who have no business being in the business. For instance, there are containers into which one may place bombs. There are structures surrounding engine test cells as well as weapons testing sites, that would need a design basis for internal and external explosions. One can see where a building owner might be confused as identical terms can have two different meanings entirely. Maybe that's the stuff that disambiguation pages are for :-) --Achim 23:50, 3 August 2006 (UTC)

[edit] Focus

This article is not about fireproofing techniques in general, nor about testing standards. --Wtshymanski 17:56, 4 August 2006 (UTC)

[edit] Picture needed

A picture of a Pyro termination in progress, or maybe a drawing of a section through a termination, would really be useful; it would show to the reader the nature of the termination problem. --Wtshymanski 15:44, 7 August 2006 (UTC)

[edit] Stonework

Does MICC really blend in with stonework? A picture would be great. I can't visualize this - outdoor copper in my experience turns green. Wouldn't this violently contrast with stonework? Even indoors, the copper-colour wouldn't match stone. --Wtshymanski 16:41, 26 August 2006 (UTC)

[edit] MIMS - drug prescribing guide

MIMS is also a prescribing reference guide in the UK. Should MIMS go through a MIMS menu page that redirects to each?

[edit] Changes to Alternatives § by anonymous user

The last change I made to that § is factual and demonstrable. It is prudent to point to the Circuit integrity article. For anyone unfamiliar with the topic, the test procedure, whether you wrap a conventional cable externally or whether you use an inherently fire-resistive cable, does not differ. You use the same curve to obtain the fire-resistance rating. The UL as well as the NRC test regime is the same. You deleted the reference to ampacity derating. That is not based on factual considerations. Even enclosures with common conduit can have an effect. The IEEE test quantifies that effect. Using intumescent windows reduces that effect, obviously, if you know anything about thermal dynamics. For instance, Promat, as you can see here: http://www.promat.de/bbs/default.asp?PAGE=KONS uses intumescent blocks made out of BAYER Fomox, which are manufactured in the City of Cologne. They are approved by DIBt. That is one of a number of examples. For the same reason, you can get intumescent grids in place of fire dampers in Europe, certified to ISO test regimes. Why? Because the air flows through, cooling down conductors in this case, and then the whole thing swells shut in a fire. Very simple. You are also on very thin ice saying that ANY building code or regulation mandates the use of a product. If you say that, you know nothing about building codes. Building codes are not written to support any one manufacturer. They tell you the hourly rating that something has to have depending on certain factors, such as height of building, the type of occupancy and so forth. Then the way to achieve that rating is to run a fire test to obtain a certification listing and then to apply that by Listing and approval use and compliance. Codes CANNOT say what sort of products to use because the authors of the code would be in court in minutes for trade restrictions. Also, the reference I provided to the IEEE standard provides a brief synopsis of the test, which is all that is needed here. This article is not intended to duplicate a standard that is copyrighted and for sale by a standards writing organisation. The article merely points to its existence and what it's about. Your statement that you have to become a member is absolutely absurd. When you go to the link you can get a synopsis of the document and if you're so inclined you can buy it. Wiki articles are supposed to provide references so that the text is verifiable, unlike your statement that codes require MI cable for anything, which is utter nonsense. If you want to make such a statement, you had better have back-up. I provided back-up for my changes. If you can back up yours, I'll be glad to revise my opinion, but so far, you're simply an anonymous user who does not like the facts I have back-up for. Please keep that in mind, because I will watch this one. --Achim (talk) 04:22, 5 December 2007 (UTC)