Motor Cable Shield; Selecting The Control Cables; Connection Of A Motor Temperature Sensor To The Drive - ABB MicroFlex e190 User Manual

46 Planning the electrical installation
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Motor cable shield

To function as a protective conductor, the shield must have the same cross-sectional
area as a phase conductor when they are made of the same metal. To effectively
suppress radiated and conducted radio-frequency emissions, the shield conductivity
must be at least 1/10 of the phase conductor conductivity. The requirements are
easily met with a copper or aluminum shield. The minimum requirement of the motor
cable shield of the drive is shown below. It consists of a concentric layer of copper
wires with an open helix of copper tape. The better and tighter the shield, the lower
the emission level and the bearing currents.
Insulation jacket

Selecting the control cables

It is recommended that all control cables be shielded.
Double-shielded twisted pair cable is recommended for analog signals. For pulse
encoder cabling, follow the instructions given by the encoder manufacturer. Use one
individually-shielded pair for each signal. Do not use a common return for different
analog signals.
Double-shielded cable (Figure a) is the best alternative for low-voltage digital signals
but single-shielded twisted multi-pair cable (Figure b) is also usable.
Run analog and digital signals in separate cables.
Never mix 24 VDC and 240 VAC signals in the same cable.
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Connection of a motor temperature sensor to the drive

See page 58.
Copper wire screen Helix of copper tape
a
Inner insulation
Cable core
b