General Machine Products 70046 Strand Tensionmeter - Manual (Page 7)

7
Line charts are provided in these instructions in or-
der for the user to determine how to compensate for
changes in ambient temperature. The charts are de-
rived from the recommended values expressed in
the referenced industry standard practices. They are
not intended to supersede any tension calculations
which might be provided to the user by the utility's
plant engineering department.
For example, assume that the engineering specifica-
tions for tensioning a certain 300 ft. span of 1/4"
Extra-High Strength strand (i.e. Bell System 6.6M)
calls for the strand to be at 600 lbs. at 60 degrees F.
When you are at the work site, your thermometer
indicates an ambient temperature of 86 degrees. Re-
ferring to the Temperature Compensation Chart for
that specific strand, you will see three lines. Find
the one which corresponds to spans 250-450 feet.
Notice that 600 pounds on the vertical axis corre-
sponds to 60 degrees on the horizontal axis. Now
continue right along the horizontal axis to 86 de-
grees. With a straight edge, follow from that point
vertically until you intersect with the 250-450 ft.
line. 86 degrees corresponds to just over 500
pounds. That is the strand tension compensated for
86 degrees ambient. On the Tensionmeter Calibra-
tion Chart for 1/4" EHS, locate 500 Ibs. and convert
to the dial indicator reading. That is the dial indica-
tor number to shoot for when tensioning this par-
ticular strand.
An analog thermometer is provided in each Strand
Tensionmeter storage case for the purpose of accu-
rately determining the ambient temperature at the
time of the measurement. Be sure to hold the ther-
mometer by the dial and not by the sensing stem
and to allow at least two minutes for the thermome-
ter to stabilize itself.
Temperature
Compensation
Charts
(continued)