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Old January 23rd 06, 12:07 AM posted to rec.radio.amateur.antenna
Ralph Mowery
 
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Default Pulling Cable in Conduit


"gb" wrote in message
...
"Ralph Mowery" wrote in message
ink.net...

"gb" wrote in message
...
"jimbo" wrote in message
. ..
I am getting close to pulling some cable through a 1 1/4 inch PVC
conduit
that runs about 20 feet from the third floor attic to the basement.

The
contractor claims the conduit is a "straight shot" with no bends. I

have
three LMR240 cables with PL259 connectors on each end. And I would

also
like to pull a 450 ohm length of ladder line. (Measures about 1 inch.)

And
I would like to pull at least two 16 gage insulated control wires.

Any advice would be appreciated.

Thanks, jimbo


A Google search should get you the electrical handbooks and codes (e.g.
NEC ) for the maximum fill for each conduit size. As a rough rule

NEVER
fill a conduit more than 70% to 75%.


The NEC is mostly for wires for the AC lines. It will not apply for the
antenna wires.

The ladder line is not going to work too well in the conduit with the
other
wire. There is a minimum distance that it should be placed from other
conductors.

Ralph -

I am not referring to the AC portion of the NEC, RATHER I am trying to
highlight the maximum fill (diameter of each cable and maximum pull).
ever try to "pull conductors" through conduit when this rule is NOT

followed
??

I have, it's pain .. in the xxxx.
Easy read and math calculations are minimal with tables supplied ---

number
of conductors and O.D. versus the I.D. on conduit.


Yes, I have. I work at a large industral plant. Some of the wire I have
pulled has been in 1 inch conduit that was probably 90% full of # 12 wire
already. Still needed to get another pair of wires through that. I have
cut a couple of wires in the conduit and used them to pull in wire to
replace them and two new wires. No room in the conduit to push a snake
through and pull the new wire in. Use lots of the wire pulling grease.
Most of the wires are control wires and only have about an amp or less on
them. We are not worried about overheating the wires in the conduit, but
need to add new control circuits to a 40 year old plant. As you said it is
a pain.