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#35488 03/12/04 03:47 AM
Joined: Jul 2002
Posts: 8,443
Likes: 3
Trumpy Offline OP
Member
What exactly is a kcmil?.
I realise that it is used on the larger sizes of wire in the US, but what does this term mean?
Sorry but I don't understand this term. [Linked Image]

#35489 03/12/04 05:14 AM
Joined: Jan 2003
Posts: 4,391
I
Moderator
Mike take a look here.

http://www.bluesea.com/techtalk/circularmils.htm

This is a little dated as they say MCM we used to use that term now we use Kcmil.

It is the same measurement with a different abbreviation.

Bob


Bob Badger
Construction & Maintenance Electrician
Massachusetts
#35490 03/12/04 05:19 AM
Joined: Jan 2003
Posts: 4,391
I
Moderator
[Linked Image from bluesea.com]

1 Circular Mil = 1 cmil

1000 Circular Mil = 1 Kcmil

A 250 Kcmil conductor is a conductor with an area of 250,000 Circular Mils

[This message has been edited by iwire (edited 03-12-2004).]


Bob Badger
Construction & Maintenance Electrician
Massachusetts
#35491 03/12/04 08:23 AM
Joined: Jul 2002
Posts: 8,443
Likes: 3
Trumpy Offline OP
Member
Iwire,
Thanks, mate!. [Linked Image]
We have a term over here in New Zealand, (and this is used in a few Non-US countries)
it is called Square Millimetres and gives the Cross-sectional Area of a particular wire or cable, based on the size of the individual wires and the number of such wires.
Here, the wires number 1,3,7,19, in numbers of strands, as the cables get bigger.
That doesn't include CEMPEX flexible Mains conductors that we use inside switch panel enclosures, that may have up to 2000 fine wires, but has the same size as a 1/0 conductor.
Different strokes for different folks, you know!. [Linked Image]

#35492 03/12/04 10:50 AM
Joined: Sep 2002
Posts: 1,498
Likes: 1
C
C-H Offline
Member
Rule of thumb: 1 sq mm = 2 kcmil

#35493 03/12/04 08:25 PM
Joined: Dec 2001
Posts: 444
S
Member
A little history about MCM.... The first M is Italian for "mille" which means thousand. For some strange reason, it got changed to KCM, I believe to mean "Kilo".

#35494 03/13/04 07:19 AM
Joined: Jul 2002
Posts: 8,443
Likes: 3
Trumpy Offline OP
Member
C-H, Sandro,
Thanks for your advice. [Linked Image]
I just have a wee bit of trouble getting my head around that term.
I think that it is because it is not a familiar one, ie not Metric!. [Linked Image]

#35495 03/13/04 09:48 AM
Joined: Sep 2003
Posts: 650
W
Member
I believe that the change from the use of M to mean 1000x to the use of K is part of a general trend to use metric prefixes. If CM is circular mil, then is MCM 1000000 circular mils or 1000 circular mils.

The problem is that depending upon where you are coming from, the answer is _clearly_ 1000, unless you come from some place where the answer is _clearly_ 1000000.

-Jon

#35496 03/13/04 09:58 AM
Joined: Nov 2003
Posts: 127
S
Member
In our state DOT we still use "M" gallons for measurement/payment of water to construction contractors. Apparently it continues to confuse some people from what I've heard. I would much rather use K gallons (or circular mils) instead, it seems that a lot more folks understand K = 1,000 from my experience.


No wire bias here- I'm standing on neutral ground.
#35497 03/13/04 11:29 AM
Joined: Apr 2001
Posts: 507
G
Member
FWIW.....

MCM is still the common term here. I see kcmil on engineering drawings but that is about it's only usage.
I guess we are just slow to change the old ways.

GJ

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