If you have a raceway that has motor control circuit conductor and more than 3 motor circuit conductors in the raceway, are you required to derate the motor circuit conductors?
If you have a raceway that has motor control circuit conductor and more than 3 motor circuit conductors in the raceway, are you required to derate the motor circuit conductors?
Don, Illinois
"It is the first responsibility of every citizen to question authority." B Franklin
TTBOMK, yes.Originally Posted by don_resqcapt19
Whomever says or otherwise portrays "I am there" is a liar.
I believe I agree with Smart. Not sure if it applies, but If surface metal raceway, then see 386.22.
Only you will see your way to the top, but you must apply yourself to get there!
Since the OP mentions the more generic term raceway, that's a very good point. Also needing noted are wireway and cable tray installations having different derating requirements.
Whomever says or otherwise portrays "I am there" is a liar.
I was not really thinking about raceways other than conduit.
Don, Illinois
"It is the first responsibility of every citizen to question authority." B Franklin
Neither was I in my first reply
Whomever says or otherwise portrays "I am there" is a liar.
I have always thought that the control conductors do not have to be counted as current carrying conductors when derating conductor ampacities. It has been a long time since I had made that conclusion and am not sure if there have been changes in code since then. What I am finding now seems to be clear that the control conductors do not need derated, but is not clear whether or not the other conductors need to include the controls when determining how many current carrying conductors are in the raceway.
I haven't looked but I think a few code cycles back some of this information was in 430 and has moved to 725, don't know if it just moved or if there were changes to the content also.725.43 Class 1 Circuit Overcurrent Protection. Overcurrent protection for conductors 14 AWG and larger shall be provided in accordance with the conductor ampacity, without applying the ampacity adjustment and correction factors of 310.15 to the ampacity calculation. Overcurrent protection shall not exceed 7 amperes for 18 AWG conductors and 10 amperes for 16 AWG.
It is still just power and lighting conductors get derated.
OP stated, "more than 3 motor circuit conductors in the raceway".
Whomever says or otherwise portrays "I am there" is a liar.
Well yes you do derate the motor conductors if more than three no matter what else is in the raceway, except cold temperature in the raceway allows for uprating on top of the derating.
Code section?
Don, Illinois
"It is the first responsibility of every citizen to question authority." B Franklin
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