DEH40635
AN 12-1007 Rev.02, 04/04/2012
Table 54.2 , Tightening torque for slotted head screws
smaller than No. 10 intended for use with 8 AWG or
smaller conductors
Slot length of screw
a
Tightening torque, lb.in
Slot width of screw
b
smaller than 0.047 in
Slot width
of screw
b
0.047 in
and
larger
<5/32
7
9
5/32
7
12
3/16
7
12
7/32
7
12
1/4
9
12
9/32
-
15
Above 9/32
-
20
a
For slot length of intermediate values, torques
pertaining to next shorter length shall be utilized. For
screws with multiple tightening means, the largest
torques value associated with the conductor size shall be
marked. Slot length shall be measured
b
Slot width is the nominal design value
Table 54.3 , Tightening torque for socket
head screws
Socket size across flat
in inches
Tightening torque in
lb.in
1/8
45
5/32
100
3/16
120
7/32
150
1/4
200
5/16
275
3/8
375
1/2
500
9/16
600
25