IS Cable Outer must be light blue

martinrclarke

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Location
singapore
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engineer
Hi
I know it is recommended practice for this to be light blue. But I have looked through the compex book and the web to see where is indicates that it is a regulation...it MUST be light blue. If another colour cable is used......is wired and run separated from other cables etc...and meets all guidelines and is not blue.....but the cable has a clear label on it indicating it is intrinsically safe...is that OK?
If it is a rule and you must follow, please point me to where is says exactly that on the web so I can quote it.

Regards
M
 

rbalex

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With regard to the US National Electrical Code (NEC), "light blue" is simply a permitted means of identification; it is not a requirement. See Section 504.80(C).

EDIT ADD: While color coding is not itself a requirement, various components of an intrinsically safe system must nevertheless be identified. See Sections 504.80(A)&(B)
 
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martinrclarke

Member
Location
singapore
Occupation
engineer
With regard to the US National Electrical Code (NEC), "light blue" is simply a permitted means of identification; it is not a requirement. See Section 504.80(C).

EDIT ADD: While color coding is not itself a requirement, various components of an intrinsically safe system must nevertheless be identified. See Sections 504.80(A)&(B)
Hi…I’m European based, so follow IEC…and whilst I see your answer is for NEC…I think it is also an IEC rule that the clout is/MUST be light blue but I can’t seem to find such a statement in IEC60079
 

GoldDigger

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This Forum is based on the NEC and to a lesser extent on the CEC (Canadian).
Not as many of our members are familiar with the IEC.
Your question is welcome, but you may not get a good answer.
 

mbrooke

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This Forum is based on the NEC and to a lesser extent on the CEC (Canadian).
Not as many of our members are familiar with the IEC.
Your question is welcome, but you may not get a good answer.


Dude! Its like you forgot about me 😢 This forum is IEC and JIS as much as it is NEC and CEC. One hails from the other.

Anyways, 5.2.2 of IEC-60446 requires light blue for the neutral or midpoint conductor.

1628736422102.png
 

GoldDigger

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Dude! Its like you forgot about me 😢 This forum is IEC and JIS as much as it is NEC and CEC. One hails from the other.

Anyways, 5.2.2 of IEC-60446 requires light blue for the neutral or midpoint conductor.

View attachment 2557546
Interestingly enough it seems to me that NOTE 1 says that light blur if used for msny specific comonents of an IS circuit (specifically those that might be considered end points or accessible points in the circuit. It says nothing aboutl either the jacket or insulation color of cable used for that IS circuit.
 

mbrooke

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Technician
Interestingly enough it seems to me that NOTE 1 says that light blur if used for msny specific comonents of an IS circuit (specifically those that might be considered end points or accessible points in the circuit. It says nothing aboutl either the jacket or insulation color of cable used for that IS circuit.


Perhaps its nothing, or perhaps there is a reason behind this. I will do some digging.

FWIW:

 

martinrclarke

Member
Location
singapore
Occupation
engineer
Hi
So I read through my Compex course notebook again…and found a single line that was very clear…IS cables should be coloured blue or clearly labeled.
Just one small line in the book.
The OR is the key. It doesn’t say it must be blue and it is the only answer…being clearly labeled and identified is also ok.

mod course all the other rules regarding IS cables involving segregation and distances must still be followed.

regards
Martin
 

rbalex

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Location
Mission Viejo, CA
Occupation
Professional Electrical Engineer
Hi
So I read through my Compex course notebook again…and found a single line that was very clear…IS cables should be coloured blue or clearly labeled.
Just one small line in the book.
The OR is the key. It doesn’t say it must be blue and it is the only answer…being clearly labeled and identified is also ok.

mod course all the other rules regarding IS cables involving segregation and distances must still be followed.

regards
Martin
And THAT is essentially the same as Section 504.80(C); i.e., light blue is a permitted means of identification but not an exclusive or required one.

The blue that mbrooke refers to is analogous to a white or gray grounded circuit conductor in the NEC. It is not a reference to an intrinsically safe application. [See Note 2 in his citation]
 
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