What are the wiring “colour code requirements” when we perform field approvals of electrical equipment?
All internal wire can be any colour.
When units of equipment are interconnected by flexible cords, cables etc., there are restrictions on green wires and white wires. If there are interconnections of units of equipment that have green wires, then they must be bond wires (or have the ends taped or painted a different colour).
If there are interconnections of units of equipment that have white wires, then they must be neutral wires (or have the ends taped or painted a different colour).
INTERNAL WIRING: SPE-1000 Section 4.14 does not mention colour coding inside equipment. We approve products to SPE-1000 with reference to other specs for areas that may be unclear or safety related.
There are a number of Canadian specifications that refer to the colour of wire, but generally they are limited to field connections only. If customers want to build to specific Canadian specifications, then they should reference the particular specification. This is not a requirement of SPE-1000 or our product approval process.
It is recommended that the equipment panels (intended for the field wiring connection point) should have an identified bond and an identified neutral terminal. If there are no terminal lugs, then the wires in the field connection panel should be white for neutral and green for bond. This will assist people that need to produce a product that is certified to a specific Canadian specification.
If customers are interested in a generally accepted colour coding scheme, then NFPA 79 is widely used. Also note that the automotive industry often uses the older (1967) Joint Industrial Council (JIC) specifications.
The customer should be aware that the time to check the circuit by the inspection group may take longer if the wiring is not colour coded. Wires may need to be traced physically or electrically.
INTERCONNECTIONS: For interconnecting units of equipment with flexible cord, section 4.12.16 states that if a green cable is used it must be for bonding. If a white cable is used it must be for a neutral. If you want to use the green or the white for something else, then the exposed ends have to be taped or sleeved with a suitable colour (other than green or white).
This section does not require the bond to be green or the neutral to be white. For example, a cable with a bond, a neutral and a control wire could all be in a 3 conductor black cable.
POWER SUPPLY CORDS: SPE-1000 section 4.7.1 defines power supply cords. These require colour coding based on the need for cables to meet SPE-1000 Table 2, which references the spec for cables (# 49). This and safety reasons would require the neutral to be white (or natural gray) and the ground to be green (Note the spec also allows the international colours of light blue for neutral and green/yellow for bond).