What is the minimum size feeder conductor for a parallel feeder?
Parallel conductor installations are covered in NEC 310.10(H) and are permitted for each phase, polarity, neutral, or grounded conductor in sizes 1/0 AWG and larger. Joining conductors in parallel is like having two or more smaller conductors connected at each end to make one larger conductor.
Which of the following is a color that can be used to designate an ungrounded conductor?
Red wires are multipurpose. Like black wires, they can be used for as ungrounded conductors. They are also commonly used as the second wire in a 220-volt installation, as a switch leg, or in a circuit that requires an interconnection, such as a smoke detector.
What 3 colors are ungrounded conductors not permitted to be?
The white conductor within a cable can be used for the ungrounded conductor if permanently reidentified at each location where the conductor is visible to indicate its use as an ungrounded conductor. Identification must encircle the insulation and must be a color other than white, gray, or green.
What are the acceptable colors of a 10 AWG grounded conductor?
1) A continuous white outer finish along its entire length. 2) A continuous gray outer finish along its entire length. 3) Three continuous white stripes along its length. 4) White or gray tape or markings at the terminations.
How many #12 Thhn wires are allowed in a 1/2 EMT?
Trade Size
| Trade Size | Wire Size (THWN, THHN) Conductor Size AWG/kcmil | |
|---|---|---|
| 12 | ||
| 1/2 | EMT | 9 |
| IMC | 10 | |
| GRC | 9 | |
Can I use a white wire as a hot?
The term “hot” is used for source wires that carry power from the electric service panel to a destination, such as a light or an outlet. Even though you are permitted to use a white wire as a hot wire by marking it with electrical tape, the opposite is not recommended or allowed.
Should there be voltage on the neutral wire?
You have to measure neutral-ground or hot-ground. If neutral-ground voltage is about 120 V and hot-ground is a few volts or less, then hot and neutral have been reversed. Under load conditions, there should be some neutral-ground voltage – 2 V or a little bit less is pretty typical.
What happens if the neutral wire is not connected?
If the neutral wire is broken or disconnected, the out of balanced current cannot return to the supply through the star point, but it must return. So, this current takes the path back to the supply through the lines.
What happens if you mix up black and white wires?
The light will work either way. The problem is, when you have the neutral and switched leg reversed, you now have the screwshell of the fixture, energized. If, when you change the lamp and touch the shell, while touching something grounded, guess where the current goes!
What happens if hot and neutral wires are reversed?
This happens when the hot and neutral wires get flipped around at an outlet, or upstream from an outlet. Reversed polarity creates a potential shock hazard, but it’s usually an easy repair. One of these wires is connected to the earth, or ‘grounded’, so this wire is called the grounded conductor.
What happens if you wire something backwards?
If your outlet’s polarity is reversed, it means that the neutral wire is connected to where the hot wire is supposed to be. This may not sound like a terrible thing, but it is. There is always electricity flowing out of an outlet with reversed polarity, even if an appliance is supposed to be off.
How much does it cost to fix reverse polarity?
Repair / Replacement Prices for Common Problems
| Roofing | |
|---|---|
| Add new outlet / light switch | $300.00 to $400.00 |
| Add 240 volt circuit (electric dryer, stove, A/C) | $300.00 to $500.00 |
| Rewire / correct electrical outlet with no ground /reversed polarity (minus service call fee) | $10.00 to $15.00 each |
How do you test for reverse polarity?
How to Check Outlet Polarity
- Plug the black lead into the middle input at the bottom of the multimeter and plug the red lead into the right input.
- Insert one of the leads into the longer vertical opening in the outlet.
- Slide one of the leads into the hot contact and the other into the round opening.
Does voltmeter have polarity?
The voltmeter indicates polarity by direction of needle direction (analog) or sign of numerical indication (digital). If the applied voltage is of the reverse polarity (negative on red and positive on black), the meter will indicate “backwards.”
How do I check the polarity of my AC power supply?
You can confirm the polarity by using a digital multimeter. One of the quality of a good digital multimeter is that it can display negative values. This feature is needed as you don’t know the polarity. Connect your adapter as pictured below.
What if I have two black wires?
You will get a reading if one wire is hot and the other isn’t. However, if both wires are hot, the reading will be zero. However, if you need to rewire a light switch or a plug socket, you may occasionally come across two black wires. It’s essential that you determine which black wire is hot before proceeding.