210.19 (A)(1) Exception ???

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Pokesomi

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Ok i am a little confused. My school is using the 2005 NEC and have a question about 210.19 (A)(1) Exception. Is it saying that the allowable ampacity must be equal to or more than the combined loads of continus and non-continus loads? This question also relates to question 33 out of the Understanding The National Electrical Code work book for 2005.
 
Yes that is what it says but I have no idea what question 33 is?

Basically the branch circuit conductors must be capable of carrying the load of the circuit. If part of the circuit is non continuous and the other continuous then it must carry the load equivalent for both.

Say you have 2 loads of 10 amps and 5 amps. The 5 amps is continuous so we must add the 10 amps plus 125% of the 5 amps. 10 + 6.25= 16.25. The conductor must be sized for the 16.25 amp load not 15 amps.
 
Pokesomi said:
Ok i am a little confused. My school is using the 2005 NEC and have a question about 210.19 (A)(1) Exception. Is it saying that the allowable ampacity must be equal to or more than the combined loads of continus and non-continus loads? This question also relates to question 33 out of the Understanding The National Electrical Code work book for 2005.
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So what is the question?
 
Pokesomi said:
Ok i am a little confused. My school is using the 2005 NEC and have a question about 210.19 (A)(1) Exception. Is it saying that the allowable ampacity must be equal to or more than the combined loads of continus and non-continus loads? This question also relates to question 33 out of the Understanding The National Electrical Code work book for 2005.
Click to expand...

The exception is for where the assembly, including the OCPD protecting the branch circuits is listed for operation at 100% of its rating. Under this exception you do not need to add 25% to the continuous load. The ampacity of the conductors shall be permitted to be equal to or greater than the combined load of the continuous and noncontinuous load.
 
Realize that this question is relating to a breaker that is listed for operation at 100% ampacity. A standard breaker is used at 80% of it's ampacity for continuous loads.
 
The Question is "Branch-circuit conductors that supply a continuous load, or any combination of continuous and non-continuous loads, must have an ampacity of not less than 125 percent of the continuous load, plus 100 percent of the noncontinuous load." its a true or false one.
 
Pokesomi said:
The Question is "Branch-circuit conductors that supply a continuous load, or any combination of continuous and non-continuous loads, must have an ampacity of not less than 125 percent of the continuous load, plus 100 percent of the noncontinuous load." its a true or false one.
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I thought I answered that? True
 
Pokesomi said:
The Question is "Branch-circuit conductors that supply a continuous load, or any combination of continuous and non-continuous loads, must have an ampacity of not less than 125 percent of the continuous load, plus 100 percent of the noncontinuous load." its a true or false one.
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Is that the exact question or is it asking about the neutral conductor.
 
yired29 said:
Is that the exact question or is it asking about the neutral conductor.
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Never mind the grounded couductor exception was added in the 08 cycle.
The answer would be true.
Unless OCPD is listed for operation at 100% of its rating.
Ignore the exception to 210.19 (A) (1) in the question unless the question stated 100% rated OCPD.
 
Pokesomi said:
thats the question verbatum
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Its true, ignoring exceptions; false if acknowledging exceptions.

Most questions ignore exceptions, especially those that are seldom used in practice... a pet peeve of mine: how is the respondant, especially one that has minimal experience, supposed to know which premise was used to write the question?
 
Smart $ said:
Its true, ignoring exceptions; false if acknowledging exceptions.

Most questions ignore exceptions, especially those that are seldom used in practice... a pet peeve of mine: how is the respondant, especially one that has minimal experience, supposed to know which premise was used to write the question?
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I agree with you. I always use to answer with the except. but I believe it was you that stated most questions ignored the except. To me the exception is part of the answer so if the question is not always true then it must be false. Unfortunately that is usually not the correct answer. :)
 
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