4-14
Practices
Cable Trays
When laying cable in cable trays, do not randomly distribute them. Power
cables for each drive should be bundled together and anchored to the tray. A
minimum separation of one cable width should be maintained between
bundles to reduce overheating and cross-coupling. Current flowing in one
set of cables can induce a hazardous voltage and / or excessive noise on the
cable set of another drive, even when no power is applied to the second
drive.
Figure 4.12 Recommended Cable Tray Practices
Carefully arrange the geometry of multiple cable sets. Keep conductors
within each group bundled. Arrange the order of the conductors to minimize
the current which induced between sets and to balance the currents. This is
critical on drives with power ratings of 200 hp (150 kW) and higher.
Maintain separation between power and control cables. When laying out
cable tray for large drives make sure that cable tray or conduit containing
signal wiring is separated from the conduit or trays containing power or
motor wiring by 3 feet or more. Electromagnetic fields from power or motor
currents can induce currents in the signal cables. Dividers also provide
excellent separation.
Bundled and
Anchored to Tray
T
PE
R S
T
PE
R S
T
PE
R S
T
PE
R S
S
R
PE
T
Recommended
arrangements for
multiple cable sets
Summary of Contents for Allen-Bradley 1305-AA02A
Page 4: ...ii Summary of Changes Notes ...
Page 40: ...2 18 Power Distribution Notes ...
Page 48: ...3 8 Grounding Notes ...
Page 68: ...4 20 Practices Notes ...
Page 78: ...6 8 Electromagnetic Interference Notes ...
Page 94: ...Glossary 4 UL Underwriters Laboratories ...
Page 100: ...Index 6 ...
Page 101: ......