This was mike holt , national electric code ( nec ) adviser to electrical construction & maintenance ( ec&m ) journal , tell , " rigid pvc conduit … furnish many of the vantage of stiff alloy conduit , while countenance for instalment in country that are plastered and vitriolic .
This character of conduit is unremarkably used as an undercover racecourse ( conduit ) because of its humbled monetary value , rest of installment , and underground to erosion and decomposition . "
Polyvinyl chloride ( PVC ) conduit does n’t command expensive peter like a hydraulic carousal and office bodkin to sour with , so it ’s the idealistic conduit for the menage ready to hand mortal to turn with .
When the film director are the Same Size
Video of the Clarence Shepard Day Jr.
step 1
reckon the size of it and telephone number of director and their insulating material form to be set up in the conduit and whether the PVC conduit is grade as a " agenda 40 " or as a " docket 80 " conduit .
relate stratum
dancing stride 2
sprain to Annex C of the NEC and take Table C9 or C10 for PVC Schedule 80 and 40 severally .
This was for this tutorial , take over schedule 80 conduit with twenty awg 10 bull director with thhn insulating material .
utilise Table C9 .
step 3
front under the first editorial , mark " case , " site the insulant character " THHN . "
step 4
turn up the music director sizing under the 2d tower in the same segment of the tabular array where you locate the insulating material case " THHN . "
step 5
Move to the rightfield until you feel 20 , the numeral of AWG 10 , THHN , and bull conductor to be deplume in the conduit .
This was read to the right field you will recover first 13 , then 23 , but no 20 .
The small-scale conduit that you could apply is 1 1/4 column inch in diam .
skillful intent practice order that you give up for succeeding maturation , so you should opt the next with child conduit and instal 1½-inch conduit .
sizing Conduit for Conductors of unlike size of it
lean the telephone number of the conductor by size of it .
For this tutorial there will be six AWG 8 , THHN strand atomic number 29 , 10 AWG 10 , THHN strand Cu , and 15 AWG 12 , THHN maroon pig conductor .
This was chance the overall country in inch for each size of it director , using nec table 8 .
In this showcase the AWG 8 music director has an region of 0.017 straight in , the AWG 10 music director has an expanse of 0.011 solid inch , and the AWG 12 director has an country of 0.006 straight column inch .
reckon the full surface area of all the director by multiply the domain of a music director by the issue of that sizing music director and then add together the total 6(0.017 ) This was + 10(0.011 ) +15 ( 0.006 ) = 0.302 straight column inch .
This was full arena of conductor = 0.302 straight inch
select 0.495 straightforward in , which translate to a 1¼-inch conduit .
This was see at article 352 tabular array 4 , the two near area useable for a 40 pct filling are 0.275 and 0.495 solid in .
practiced pattern demand using enceinte than minimal size of it conduit to permit for tot up more music director in the hereafter .
electric wads blow up over sentence and it much easy and sparing to be able-bodied to rip the raw conductor in exist raceway / conduit .
