Electrical

[Trep21]

I was doing some practice code questions. There’s was one question that asked. If you have two blue leads what would the voltage be across them?
Is 208v correct ?

 

[suemarkp]

There are no color requirements other than white, green, and orange. There is no requirement to wire different phases in different colors. But under common practices, two wires of the same color should be from the same source and leg, so voltage between them would be zero.

 

[Tulsa Electrician]

By chance was this a heat trace question.

 

[ggunn]

I was doing some practice code questions. There’s was one question that asked. If you have two blue leads what would the voltage be across them?
Is 208v correct ?

Um, zero?

 

[kwired]

My answer is it depends on what the other end is connected to.

 

[infinity]

My answer is it depends on what the other end is connected to.

Exactly. The question as written cannot be answered.

 

[tom baker]

The correct answer would be to use a voltmeter to determine voltage. It could be no voltage, 208, 240 or 480. Poor question

 

[Jraef]

Exactly. The question as written cannot be answered.

Yep. It’s like “How long is a piece of rope?”

 

[LarryFine]

Yep. It’s like “How long is a piece of rope?”

How Long is a Chinese name.

 

[Jraef]

The correct answer would be to use a voltmeter to determine voltage. It could be no voltage, 208, 240 or 480. Poor question

Or any DC control voltage in a control panel built to NFPA79 standards (because blue denotes internally derived DC control voltage). And per that, they could be different voltages in the same panel, like 24VDC and 48VDC, in which case the difference between them could be zero or 24V.

As everyone else has said, very poorly worded question obviously concocted by someone not in the trade.

 

[Jraef]

How Long is a Chinese name.

Howie Long is Chinese? Huh… doesn’t look it… but I guess maybe.