Cut Sheet

28
Technical Data TD01701001E
Effective March 2017
UL low-voltage busway
Pow-R-Way III
EATON www.eaton.com
Physical data (continued)
Expansion joints (Figure 30)
Expansion joints accommodate the expansion and contraction of
bus bars with respect to the enclosure. They compensate for the
difference in the coefficient of expansion of the aluminum housing
and the copper or aluminum bus bars. Expansion joints must be
used wherever a run of busway crosses an expansion joint of a
building. They should also be installed in the center of extremely
long straight runs of busway in which the run does not change
planes either horizontally or vertically. One expansion joint is
required every 300 ft (91 m) for copper or one every 225 ft (68 m)
for aluminum. The use of expansion joints should be engineered for
individual installations. Minimum dimensions are shown in Table 39.
ote:N All dimensions are to the centerline of the Pow-R-Bridge.
Table 39. Expansion joints
UL 857 ampere rating Dimensions in inches (mm)
Cu Al A
a
225 225 12.00 (304.8)
400 400 12.00 (304.8)
600 600 12.00 (304.8)
800 — 12.00 (304.8)
1000 — 12.00 (304.8)
1200 800 12.00 (304.8)
1350 1000 16.50 (419.1)
1600 1200 16.50 (419.1)
2000 1350 16.50 (419.1)
— 1600 16.50 (419.1)
2500 2000 20.50 (520.7)
3200 — 20.50 (520.7)
4000 2500 24.50 (622.3)
— 3200 24.50 (622.3)
5000 4000 30.25 (768.4)
a
Dimensions shown are for three-phase, three-wire and three-phase 100% neutral configurations.
Please consult factory for 200% neutral sizes.
Figure 30. Expansion joints
Phase transpositions (Figure 31 and Figure 32)
Phase transposition fittings are used in applications where a phase
rotation is needed due to a change in phasing from the source
equipment to the load equipment. Both 90° and 180° rotations
are possible. In each case, all conductors are rotated.
Figure 31. 180° transposition—dimensions in inches (mm)
a
For 5000 A Cu configuration, the box length will be 28.00 inches instead of 24.00 inches as shown.
Figure 32. 90° transposition—dimensions in inches (mm)
49.00
(1244.6)
(Minimum)
25.00
(635.0)
12.00
(304.8) (Minimum)
29.69
(754.1)
of Duct
of
Box
C
L
C
L
C
L
C
L
A
T
F