120 or 125?

[George Stolz]

Why does Article 210 make reference to 125 Volt circuits, when 220.5(A) lists 120?

Why does the code stray from 115V to 125V? Isn't this a prime target for loopholes? 210.6 uses 120V, then 210.8 switches gears to 125V. Is there a distinction I am missing, or is this just sloppy?

110.4 states:

Throughout this Code, the voltage considered shall be the voltage at which the circuit operates. The voltage rating of electrical equipment shall not be less than the nominal voltage of a circuit to which it is connected.

Doesn't this work as a fix-all for 130V lamps, and whatnot?

 

[bphgravity]

Re: 120 or 125?

For one thing, the NEC is not a product standard, so equipment, appliances, and devices will have voltage ratings that range from the nominal.

Look at the definitions of "voltage" in Article 100. 210.6 uses the terms 120 volts, nominal where as 210.8 uses just 125 volts. The reason is because receptacles are rated by a product standard (NEMA, ANSI, ect..), but 210.6 still applies because 120 volts nominal includes voltages of 115-130.

 

[kpepin]

Re: 120 or 125?

I remember back when I was in trade school, we were discussing peak demand times. The instructer plugged in his Digital Multi-Meter into an outlet in the front of the class. The voltage varried from 117V to 124V. He explained to us that the voltages will vary slightly during the day but things are generally considered to be 120 V. I don't remember the point of the discussion (I was 14 at the time) but I think iff you stick with a nominal 120V you're ok.

I like the explanation of the NEMA 125V rating. That makes sense to me. 125/250 Volt plugs are usually operating at 120/240 Volt, 300V rated disconnects usually have 240V or 208V.

 

[aelectricalman]

Re: 120 or 125?

You were in Trade School at 14 years old. Sounds a little weird to me. 8th or 9th grade is for 14 year olds. Im not questioning it, it just sounds funny.