Manual

NORD USS and Modbus RTU Manual
24 Subject to technical amendments BU 0050 GB-3111
1.4.4 Installation of the Bus System
In an industrial environment the correct installation of the bus system is particularly important in order to
reduce potential interference. The following points are designed to help prevent interference and problems
right from the start.
The installation guidelines are not complete and applicable safety and accident prevention guidelines must be
complied with.
1.4.4.1 Cable material
The frequency inverter is usually connected to the USS bus system by a twisted, shielded two-wire cable.
The guaranteed transfer speeds or transfer distances can only be achieved without errors if the specified cable
parameters are complied with.
Structural Details:
Cable diameter : 2 0,5 mm
2
Flexible strand: 16 0,2 mm
Twisting: 20 twists / m
Total shielding: Mesh, tinned copper wire,
1.1 mm
2
,
85 % visual covering
Total diameter: 5 mm
External sheath: according to requirements for
flammability, combustion residues,
etc.
Thermal / Electrical Properties:
Conductor resistance (20°C): 40 W/km
Insulation resistance (20°C): 200 W/km
Operating voltage (20°C): 300 V
Test voltage (20°C): 1500 V
Temperature range: -40 °C T 80 °C
Load capacity: 5 A
Capacitance: 120 pF/m