Difference between intrinsically safe cables and flame-retardant cables
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A batch of cables arrived today, including intrinsically safe cables. They don’t seem any different from ordinary cables; they look exactly the same. Could some expert give me some guidance?
The visible difference is that the insulation of intrinsically safe cables is blue, while that of flame-retardant cables is black... The fundamental difference lies in the manufacturing process, but this can’t be seen by eye, right?
Is there any specific rule stating that intrinsically safe cables have to be blue? The cables that arrived today are all black; it seems like intrinsically safe cables are no different from ordinary cables.
Aniline cables are generally blue, but it’s not absolute... I’m not entirely sure……
My god! The outer sheath is intrinsically safe and blue in color; it is flame-retardant and marked with ZR, or ZRA, or ZRB, or ZRC. Intrinsic safety cables are generally flame-retardant. These are all basic knowledge about instruments; if you don’t know these, it simply means you’re not yet a qualified instrument technician.
Intrinsic safety cables are blue, while non-intrinsic safety cables can be used for intrinsic safety circuits.
Are intrinsically safe cables designed for intrinsically safe circuits? I’ve used blue cables, and after expanding them, I didn’t find any difference from non-intrinsic safety ones
You judge whether a cable is intrinsically safe based solely on its color, but the cable I received was black in color and didn’t differ much from ordinary cables; I’ve always encountered blue ones. So I would like to ask you, as a qualified instrument technician, how to determine the authenticity of an intrinsically safe cable. After checking, I found that there’s no specific requirement stating that intrinsically safe cables must be blue. Please answer
The essential difference is that the inductance and capacitance per meter of intrinsically safe cables are below specified values. It is impossible to distinguish with the naked eye.
In accordance with clause 7.2.3 of the \"HG_T20512-2014 Specifications for the Design of Instrument Piping and Wiring\", when an intrinsically safe system is used, intrinsically safe cables shall be selected, and their distributed capacitance and distributed inductance parameters must meet the requirements of the intrinsically safe circuit. The outer sheath of the intrinsically safe cable is marked in blue. If your cable specification is ZR-IA-DJYPVPR and it has the IA mark, then the outer cover should be blue ； If your cable specification is ZR-DJYPVPR, then it has a black outer cover.
That is, it’s impossible to determine. Only the label and color can be seen