ECN Forum Forums Code Related Discussion Canadian Electrical Code Topics Question about 600Y347

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.?

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

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).]

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.