Danfoss VLT 2800 Manual de servicio descargar pdf (Pagina 45)

Use of EMC compliant cables

In order to comply with requirements for EMC immun-

ity of the control cables and EMC emissions from the

motor cables screened/armoured cables must be

used.

The ability of a cable to reduce the amount of ingoing

and outgoing radiation of electric noise depends on the

transfer impedance (Z

). The screen of a cable is nor-

mally designed to reduce the transfer of electric noise,

and a screen with a lower Z

is more effective than a

screen with a higher Z

is rarely stated by cable manufacturers, but it is of-

ten possible to estimate Z

by looking at and assess-

ing the physical design of the cable.

can be assessed on the basis of the following fac-

tors:

the contact resistance between the individual

screen conductors.

Screen coverage, i.e. the physical area of the

cable covered by the screen. Is often stated

as a percentage and should be no less than

85%.

The screen type, i.e. braided or twisted pat-

tern. A braided pattern or closed pipe is rec-

ommended.

VLT

2800 Series

MG.27.E3.02 - VLT

is a registered Danfoss trademark 45

Installation

1 2 ... 40 41 42 43 44 45 46 47 48 49 50 ... 170 171

Sin comentarios

Danfoss VLT 2800 Manual de servicio Pagina 45