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Open season on whites
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2018-02-12 at 1:49 AM UTC
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2018-02-12 at 1:52 AM UTC
Originally posted by Open Your Mind I don't really know I just install the stuff. The copper armor doubles as the bond/ground. Also unlike the regular armor you see on tec cable or bx, which is like tightly coiled spring, this stuff is a solid copper tube. It's rated for something like 2-3 hours in direct flame. The white stuff on the inside apparently crystallizes to protect the conductors.
I'll have to google it some time. copper is soft, a copper jacket is exponentially more expensive than just using a cable/wire, conducts heat (ie...the copper jacket is going to act like a heating element) and, i don't see why wire of that capacity needs fire protection in the first place unless that powers an emergency-related load. -
2018-02-12 at 1:55 AM UTC
Originally posted by A College Professor that looks super cool, so the jacket is your ground conductor and the cable pictured probably used as three phases and a neutral? man I bet the connectors for that are expensive.
probably the most interesting cable I have worked with was high voltage ( want to say around 2000v insulation ) direct burial cable for oil well pumps. had an oval cross section shape and a pretty thick lead jacket spiral wrapped. individual conductors were solid and tinned, roughly 10awg and had REALLY fat insulation that was something pretty fancy , looked and felt similar to ptfe or teflon. can't find a picture of it shoulda saved a scrap chunk
Correct, 3 phase with a neutral.
I've only worked with high voltage cable once, we had to pull a couple kilometer long runs of it for a train yard. There was a special procedure for splicing it, these rubber "boots" would cover each splice. -
2018-02-12 at 1:58 AM UTC
Originally posted by infinityshock I'll have to google it some time. copper is soft, a copper jacket is exponentially more expensive than just using a cable/wire, conducts heat (ie…the copper jacket is going to act like a heating element) and, i don't see why wire of that capacity needs fire protection in the first place unless that powers an emergency-related load.
We did pull it in for emergency purposes. I think it's over kill, the whole electrical room could be burning but these cables are supposed to survive...
I'll try to remember the specific name of this cable. -
2018-02-12 at 2:06 AM UTC
Originally posted by Open Your Mind Correct, 3 phase with a neutral.
I've only worked with high voltage cable once, we had to pull a couple kilometer long runs of it for a train yard. There was a special procedure for splicing it, these rubber "boots" would cover each splice.
you should try the thermite shit sometime. I can't remember what it's called. -
2018-02-12 at 2:08 AM UTC
Originally posted by Open Your Mind We did pull it in for emergency purposes. I think it's over kill, the whole electrical room could be burning but these cables are supposed to survive…
I'll try to remember the specific name of this cable.
it could be feeding a fire pump...communications system...emergency machinery...emergency lighting...who knows, but I still don't get the copper outer jacket. -
2018-02-12 at 2:26 AM UTC
Originally posted by infinityshock it could be feeding a fire pump…communications system…emergency machinery…emergency lighting…who knows, but I still don't get the copper outer jacket.
From what I have seen it is only being used as the feeders for certain panels on the upper floors... but all the lights / loads tied into these panels are regular wire pulled through regular EMT. -
2018-02-12 at 3:24 AM UTC
Originally posted by Open Your Mind From what I have seen it is only being used as the feeders for certain panels on the upper floors… but all the lights / loads tied into these panels are regular wire pulled through regular EMT.
i have no idea. its not something ive ever heard of. anything im familiar with that is electrical wiring/fire line (water) that needs to be fire 'proof' is run through the steel structural members that get cocooned in fire 'proof' spray-foamy-cementious-shit...which is supposed to protect the steel structure at the same times as the conduit/piping. -
2018-02-12 at 3:57 AM UTC
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2018-02-12 at 4:05 AM UTC
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2018-02-12 at 6:16 PM UTC
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2018-02-12 at 6:27 PM UTC
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2018-02-12 at 6:35 PM UTCi just googled it.
Typically, these cables are used wherever there is a need for life safety of occupants and the need to keep critical circuits functioning to aid in their safe egress.
Critical circuits typically include feeders for fire pumps, elevators, smoke control equipment, fire alarm systems and other similar circuits.
The National Electrical Code (NEC) requires that these critical circuits have a 2-hour fire rating. This code has been structured to allow additional time for building occupants to exit a building during an emergency and to provide uninterrupted power for fire fighting equipment and emergency communication systems. That’s also required where occupant mobility is limited and time must be allowed for egress, such as in hospitals and other institutions that care for people. Fire-rated cables also offer enhanced protection for airports, railway tunnels, data centers, and other critical applications.
what makes no sense is using copper as the outer jacket for fire protection.
an appropriate analogy is copper with heat is like a sponge with water...it sucks it in and holds it.
a better choice would have been aluminum, which is more like a water-repellent piece of cloth...it defects it and while it will hold a small amount, it doesnt hold on to it for very long.
anyone that does welding knows what pain in the dick it is to weld aluminum for this exact reason. -
2018-02-12 at 6:38 PM UTC
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2018-02-12 at 6:41 PM UTC
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2018-02-12 at 6:45 PM UTC
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2018-02-12 at 6:45 PM UTC
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2018-02-12 at 6:46 PM UTC
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2018-02-12 at 6:50 PM UTC
Originally posted by infinityshock eggzactly. itll conduct the heat right into the wires/jackets/insulation
heat are like electricity, they will always prefer to flow thru the path of least resistance.
the inch thick insulation means that heat will spread along the length of the copper jacket faster than into it. -
2018-02-12 at 6:53 PM UTC
