Rockwell Automation TLY-Series Servo Motor - Manual (Page 7)

TL-Series Servo Motors 7
Publication TL-IN003A-EN-P — June 2007
Interconnect Cables
Knowledgeable cable routing improves system electromagnetic compatibility (EMC). Refer to
Shielding of Brake Wires Within the Power Cable on page 9 for cable shield grounding at the servo
drive.
Follow these steps to install the cables.
1. Keep wire lengths as short as physically possible.
2. Route signal cables away from motor and power wiring. Typical signal cables transmit
encoder, serial, or analog data at low voltages.
3. Separate cables by 0.3 m (1 ft) minimum for every 9 m (30 ft) of parallel run.
4. Ground both ends of the cable shield and twist the signal wire pairs to prevent
electromagnetic interference (EMI) from other equipment.
Electrical Noise
ElectroMagnetic Interference (EMI), commonly called noise, adversely impacts motor performance
by inducing stray signals. Effective techniques to counter EMI include filtering the ac power,
shielding and separating signal carrying lines, and practicing good grounding techniques. Effective ac
power filtering can be achieved by using isolated ac power transformers or properly installed ac line
filters.
To reduce EMI follow these guidelines:
• Physically separate signal lines from motor cabling and power wiring. Do not route signal
wires with motor and power wires, and do not route signal wires over the vent openings of
servo drives or other electrical power sources.
• Ground all equipment by using a single-point parallel ground system that employs ground bus
bars or large straps. If necessary, use additional electrical noise reduction techniques to reduce
EMI in noisy environments.
ATTENTION
High voltage can be present on the shields of a power cable, if the shields are
not grounded.
Verify there is a connection to ground for all shields in the power cable.
Failure to observe these safety procedures could result in personal injury or
damage to equipment.