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Posted By: CTwireman Question about 600Y347 - 02/14/02 12:45 AM
Do you use 600Y347 instead of 480Y277 in Canada, or are both voltages available?

What is the commonly used color-coding for a 600/347 volt system?

As you probably know allready we use brown-orange-yellow-gray for 480.

Any idea why 600 is not used in the U.S.?
Posted By: Tony Moscioni Re: Question about 600Y347 - 02/14/02 09:33 PM
In Canada, the primary voltage for industrial / commercial secondary distribution is 347/600v.

However, you can also spec 277 / 480v if so desired.

The automotive industry and most of it's subsidaries use the 480 volt secondary distribution system.


Rule 4-036 Colour of Conductors

Where colour coded circuits are required, the following colour coding shall be used, except in the case of service-entrance cable and insofar as Rules 4-030, 4-032, and 6-308 may modify these requirements:

1 phase ac or dc (2-wire) — 1 black and 1 red
or
1 black and 1 white*† (where identified conductor is required);
1 phase ac or dc (3-wire) — 1 black, 1 red, and 1 white*†;
3 phase ac — 1 red (phase A),
1 black (phase B),
1 blue (phase C), and
1 white* (where neutral is required)
*Or natural grey;
†Or white with coloured stripe (see Subrule 4-034).
(4) Where the mid-point of one phase of a 4-wire delta-connected secondary is grounded to supply lighting and similar loads, the conductors shall be colour coded in accordance with Subrule (3) and the phase A conductor shall be the conductor having the higher voltage-to-ground.


Rationale for Rule 4-036.
It is desirable that there be a universal or at least a national colour code for conductors, rather than several varieties, to avoid confusion and provide greater safety.

Intent for Rule 4-036.
In Subrule (3), we intend that when colour-coded circuits are required, phase A conductors be coloured red, phase B conductors be coloured black, phase C conductors be coloured blue, and the neutral conductors be coloured white or white with a coloured stripe where more than one system is present in the raceway, box, or enclosure.
In Subrule (4), occasions arise where a delta-connection secondary is grounded to supply lighting and similar loads in addition to polyphase motors, so that the one phase has a higher voltage-to-ground than the other two phases. We intend that this phase be designated as Phase A and the conductors coloured red as per Subrule (3).

Tony Moscioni
Electrical Inspector
Electrical Safety Authority
Posted By: CTwireman Re: Question about 600Y347 - 02/15/02 12:20 AM
Thanks for your answers.

The brown/orange/yellow/gray is not a code requirement here in the US, but it is commonly used and specified.

How do you differentiate between different voltage systems in a building, ie, a building with 600/347 and 120/208? If I interpret the CEC rule correctly, do different voltage systems utilize the same color code?

120/240 is also a common voltage system in Canada, right?

I am under the impression that US and Canadian systems are similar but there are also some big differences.

[This message has been edited by CTwireman (edited 02-14-2002).]
Posted By: ggardiner Re: Question about 600Y347 - 02/15/02 06:43 PM
Most of us use the brown yellow orange for 600 volt wiring.I'm not sure if this was changed in the 2002 code but I know it not a code but a trade practice.
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