Electric Power Generation, Transmission, and Distribution

14.6.3.3 Sagging Accuracy

Sagging a conductor during construction of a new line or in the reconductoring of a old line involves many
variables that can lead to a small degree of error. IEEE Std. 524–1993 suggests that all sags be within 6 in. of
the stringing sag values. However, aside from measurement errors during sagging, errors in terrain
measurement and variations in conductor properties, loading conditions, and hardware installation
have led some utilities to allow up to 3 ft of margin in addition to the required minimum ground clearance.

14.6.3.4 Clipping Offsets

If the conductor is to be sagged in a series of suspension spans where the span lengths are reasonably
close and where the terrain is reasonably level, then the conductor is sagged using conventional stringing
sag tables and the conductor is simply clipped into suspension clamps that replace the travelers. If the

TABLE 14.14 Typical Sag and Tension Data 795 kcmil-37 Strand AAC ‘‘Arbutus,’’ 300- and 1000-ft Spans

Conductor: Arbutus
795 kcmil-37 Strands AAC Span¼300 ft
Area¼0.6245 in.^2
Creepisa factor
Final Initial

Temp, 8 F Ice, in.

Wind,

lb=ft^2 K, lb=ft

Weight,

lb=ft Sag, ft

Tension,

lb Sag, ft

Tension,
lb
0 0.50 4.00 0.30 2.125 3.97 6033 3.75 6383
32 0.50 0.00 0.00 1.696 4.35 4386 3.78 5053
 20 0.00 0.00 0.00 0.746 1.58 5319 1.39 6055
0 0.00 0.00 0.00 0.746 2.00 4208 1.59 5268
30 0.00 0.00 0.00 0.746 2.91 2889 2.06 4075
60 0.00 0.00 0.00 0.746 4.03 2085 a 2.80 2999
90 0.00 0.00 0.00 0.746 5.13 1638 3.79 2215
120 0.00 0.00 0.00 0.746 6.13 1372 4.86 1732
167 0.00 0.00 0.00 0.746 7.51 1122 6.38 1319
212 0.00 0.00 0.00 0.746 8.65 975 7.65 1101
aDesign condition.

Conductor: Arbutus
795 kcmil-37 Strands AAC Span¼1000 ft
Area¼0.6245 in.^2
Creepisa factor NESC Heavy Loading District
Final Initial

Temp, 8 F Ice, in.

Wind,

lb=ft^2 K, lb=ft

Weight,

lb=ft Sag, ft

Tension,

lb Sag, ft

Tension,
lb
0 0.50 4.00 0.30 2.125 45.11 59.53 44.50 6033
32 0.50 0.00 0.00 1.696 45.80 4679 44.68 4794
 20 0.00 0.00 0.00 0.746 40.93 2300 38.89 2418
0 0.00 0.00 0.00 0.746 42.04 2240 40.03 2350
30 0.00 0.00 0.00 0.746 43.66 2158 41.71 2258
60 0.00 0.00 0.00 0.746 45.24 2085 a 43.32 2175
90 0.00 0.00 0.00 0.746 46.76 2018 44.89 2101
120 0.00 0.00 0.00 0.746 48.24 1958 46.42 2033
167 0.00 0.00 0.00 0.746 50.49 1873 48.72 1939
212 0.00 0.00 0.00 0.746 52.55 1801 50.84 1860
aDesign condition.
Note:Calculations based on:(1) NESC Light Loading District. (2) Tension Limits: a. Initial Loaded – 60% RBS @ 0 8 F;
b. Initial Unloaded – 25% RBS @ 60 8 F; c. Final Unloaded – 15% RBS @ 60 8 F.