ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
ShoutChat
Recent Posts
Increasing demand factors in residential
by gfretwell - 03/28/24 12:43 AM
Portable generator question
by Steve Miller - 03/19/24 08:50 PM
Do we need grounding?
by NORCAL - 03/19/24 05:11 PM
240V only in a home and NEC?
by dsk - 03/19/24 06:33 AM
Cordless Tools: The Obvious Question
by renosteinke - 03/14/24 08:05 PM
New in the Gallery:
This is a new one
This is a new one
by timmp, September 24
Few pics I found
Few pics I found
by timmp, August 15
Who's Online Now
1 members (gfretwell), 32 guests, and 14 robots.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Page 1 of 2 1 2
#124171 08/20/06 07:50 AM
Joined: Dec 2000
Posts: 4,294
Member
Rewired has been exploring again [Linked Image]


Quote
I happened to stumble on this in the girlfriends apartment building(s).
The " 550" and " 575" amp fuses are in the main disconnect of two of the buildings, the " 380" amp fuses are in a third building which actually has TWO main services, one for the units, one (225 amp main breaker) for the house load and now disconnected electric hot water tanks. ( all had electric hot water at one time, only the other buildings brought in a 100A gooV 3 phase service for the tanks, all of which is now disconnected..

I found a couple good violations that I will post later


[Linked Image]


[Linked Image]


[Linked Image]


[Linked Image]


[Linked Image]

#124172 08/20/06 11:02 PM
Joined: Feb 2006
Posts: 144
N
Member
Individual runs of copper water pipe? That's crazy!

Those also look like custom made fuses. It looks like the ratings were probably hand stamped on them. Those are pretty cool, so long as theyre used properly

#124173 08/20/06 11:40 PM
Joined: Oct 2004
Posts: 806
Member
Don't think that's water pipe, but a metal-encased, mineral powder filled (as insulation) cable. I forget the tradename, but there was a thread about it on here somewhere....


Stupid should be painful.
#124174 08/21/06 01:09 AM
Joined: Jul 2002
Posts: 8,443
Likes: 3
Member
Pyrotenax. [Linked Image]

#124175 08/21/06 07:16 AM
Joined: Jan 2003
Posts: 4,391
I
Moderator
In the NEC it is called MI Cable.

It is fireproof (more or less) it can operate even while sections of it are exposed to open flame.

A typical use of it is for life safety emergency circuits.

The insulation between the copper conductor and the copper sheath looks like Sheetrock and is somewhat flexible until exposed to high heat than I believe it turns hard more like ceramic.


Bob Badger
Construction & Maintenance Electrician
Massachusetts
#124176 08/21/06 03:12 PM
Joined: Dec 2005
Posts: 869
Likes: 4
R
Member
or MIMS

Mineral Insulated Metal Sheethed


The product of rotation, excitation and flux produces electricty.
#124177 08/21/06 05:43 PM
Joined: Jan 2006
Posts: 558
R
Member
Just an off the wall question but do you think they used this type of conductor because it basically runs unfused from the service head ( between the 2nd and 3rd floors) down to the sub basement where the disconnect is located... I assume they would have to have buried it in the masonry and concrete slab for protection?!?!
Doesnt seem correct, but thats how it was done 40+ odd years ago.

A.D

#124178 08/21/06 08:42 PM
Joined: Jul 2002
Posts: 8,443
Likes: 3
Member
Here is the thread where MI (pyro) cable was discussed. [Linked Image]

{Message edited to fix tag}

[This message has been edited by Trumpy (edited 08-21-2006).]

#124179 08/21/06 11:27 PM
Joined: Jan 2006
Posts: 558
R
Member
Very cool! I will be definately looking up more information on pyro cables. That is the first time I have actually seen it installed and in service. Too bad its not too popular here any more, I would have really liked to get lessons on how to properly install pyro and get some hands on experience installing the stuff.

A.D

#124180 08/22/06 07:32 AM
Joined: Nov 2000
Posts: 2,148
R
Member
It looks like the lock nuts on the MI connectors are ferrous. That could be a problem. It apprears that the 3 MI connectors enter the enclosure via some type of plate that is bolted to the inside of the enclosure. I assume that is nonferrous to pevent induction heating.
Don


Don(resqcapt19)
Page 1 of 2 1 2

Link Copied to Clipboard
Powered by UBB.threads™ PHP Forum Software 7.7.5