Mike Dolt Enterprises
Mike Dolt Enterprises
User: PaulWDent, Location: Logan, Utah
Asked on: Tuesday, March 22, 2011 at 2:42 pm EDT
Answered on: Tuesday, May 14, 2024 at 3:06 am EDT
Question: I just learned that some manufacturers are headed in the direction of standardizing on black and white on the DC side, where black is +ve (!!!!) and white is -ve. This is already causing some electricans to tear their hair out. Especially when an inverter allows you to select operation with either a positive ground array or a negative ground array by setting an internal switch and moving the GFDI fuse. If you do select negative ground, then you have white as the negative and ungrounded conductor carrying maybe 600vDC while black is the grounded conductor!!Do we think this is smart?I say let us suggest that the color code be Red for +ve, Black for -ve, and either one or neither can be grounded (depending on whether it is a +ve ground, -ve ground or balanced system) but, when the GFDI operates, both are potentially "hot" anyway (as the madatory warning label says) , so the colors black and red seem appropriate.
The standardization of black and white on the DC side, with black being positive and white being negative, is a matter of contention within the electrical industry. While it may seem counterintuitive to have the black wire as positive and the white wire as negative, there are some arguments in favor of this approach.
Arguments in favor of standardizing on black and white
Consistency with household wiring
In most households, black is used for the hot wire and white is used for the neutral wire. This color coding is familiar to electricians and homeowners alike, making it easier to identify and work with DC wiring.
Avoidance of confusion with AC wiring
In AC systems, black is typically used for the hot wire and white is used for the neutral wire. By standardizing on black and white for DC wiring, it can help to avoid confusion between AC and DC systems.
Simplified troubleshooting
If a DC wire is damaged or disconnected, it can be easily identified by its color coding. This can help to speed up troubleshooting and reduce the risk of electrical accidents.
Arguments against standardizing on black and white
Deviation from conventional wiring practices
The traditional color coding for DC wiring is red for positive and black for negative. By switching to black and white, it could potentially create confusion for electricians who are accustomed to the old color scheme.
Increased risk of polarity reversal
If a DC wire is connected incorrectly, it can cause damage to equipment or electrical hazards. By having black as positive and white as negative, it increases the risk of polarity reversal, as electricians may be more likely to assume that black is always hot.
Confusion with grounded systems
In some DC systems, the negative terminal is grounded. If the white wire is used as the negative wire, it could create confusion with grounded AC systems, where the white wire is typically used as the neutral wire.
Conclusion:
Ultimately, the decision of whether to standardize on black and white for DC wiring is a complex one with pros and cons to consider. While there are some arguments in favor of this approach, there are also significant concerns that need to be addressed. The electrical industry will need to carefully weigh the benefits and risks before making a final decision. Flag for review