MEGA MC Cable Installation & Application Guide - Southwire

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Multiple conductors—Maximum pulling tension for multiple conductors in parallel, or multiplexed,
and multiple conductor cables.
Three or fewer conductors
Tcable = N T c pounds
More than three conductors
Tout = –WL + T in pounds
horizontal straight sections—The tension for a horizontal straight section of cable can be
estimated with the following equation.
T =
out
pounds
Where: T = tension out of a section in pounds
out
µ = coefficient of dynamic friction ( µ = 0.15)
W = total cable assembly weight in pounds/foot
L = straight section length in feet
T = tension into a section in pounds
in
The coefficient of friction (μ) equal to 0.15 accounts for the low rolling friction of
well-maintained rollers.
inclined straight section—Use the following equation for pulling up an inclined straight section.
Use the following equation for pulling down an inclined straight section.
Where: T = tension out of a section in pounds
out out
W = total cable assembly weight in pounds/foot
θ = straight section angle from horizontal in radians
L = straight section length in feet
µ = coefficient of dynamic friction ( µ = 0.15)
T = tension into a section in pounds
in
vertical v sections— When pulling straight up or down, the equation for inclined pulls simplifies to
the following equations.
Pulling straight up
Tout = WL + T in in pounds
Pulling straight down
Tout = –WL + T in pounds
pounds
pounds
Where: W = total cable assembly weight, in pounds/feet
L = straight vertical section length, in feet
tension t in bends—If the sheaves are well maintained, they will not have the multiplying effect on
tension that bends in conduit have. The sheaves will turn with the cable, allowing the coefficient
Southwire MC inStallation Guide section 4. AnneXes