Different Colors Used in Electrical Wiring

What colors are typically used for the following in electrical wiring:

1. AC Control circuit 150 volts or less?

2. Voltages over 150 volts?

3. DC Control Circuit 150 volts or less?

4. Wire that is not de-energized when disconnect is off?

5. Equipment grounding (non-current carrying)?

6. Grounded Circuit (current carrying)?

Answers:

1. For AC Control circuit 150 volts or less, typically blue or yellow wiring is used.

2. For voltages over 150 volts, colors can vary, but often black or red wires are used.

3. For DC Control Circuit 150 volts or less, white or grey wiring is usually used.

4. Wires that are not de-energized when the disconnect is off are usually red or black.

5. For equipment grounding (non-current carrying), a green or bare wire is commonly used.

6. For Grounded Circuit (current carrying), white or grey wiring is utilized.

Explanation:

Different electrical circuit elements have specified wiring colors for clarity and safety. The primary difference between THHN and MTW wire is in their application and coating. A diode in parallel to a relay protects from kickback voltage. CRM and PLC stand for Customer Relationship Management and Programmable Logic Controller, respectively.

The different circuitry systems typically use different colors for their wiring to denote their functioning. Widely, the color codes are: 1. For AC Control circuit 150 volts or less, typically blue or yellow wiring is used. 2. For voltages over 150 volts, colors can vary, but often black or red wires are used. 3. For DC Control Circuit 150 volts or less, they usually use white or grey wiring. 4. Wires that are not de-energized when the disconnect is off are usually red or black. 5. For equipment grounding (non-current carrying), a green or bare wire is commonly used. 6. For Grounded Circuit (current carrying), white or grey wiring is utilized.

The difference between THHN and MTW wire: THHN is thermoplastic, high-heat-resistant nylon-coated wire, and is typically used in dry locations for conductor wiring or grounding. THHN wires have a solid or stranded bare copper core, with a nylon wire jacket that resists heat, oil, and gasoline. MTW wire, or Machine Tool Wire, is insulated copper electrical wire, PVC insulated, and used in manufacturing appliances and machinery. MTW wire has a broader range of applications, including both wet and dry locations. The purpose of a diode placed in parallel to a relay is to protect the circuit from damage caused by the kickback voltage produced when the relay coil is de-energized. This is known as a flyback diode.

'CRM' stands for Customer Relationship Management, and 'PLC' stands for Programmable Logic Controller.