Danfoss VLT HVAC Drive FC 100 Series Design Manual page 115

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VLT HVAC Drive Design Guide 5. How to Install
5
Illustration 5.50: EMC-correct electrical installation of a frequency converter in cabinet.
5.7.2. Use of EMC-Correct Cables
Danfoss recommends braided screened/armoured cables to optimise EMC immunity of the control cables and the EMC emission from the motor cables.
The ability of a cable to reduce the in- and outgoing radiation of electric noise depends on the transfer impedance (Z ). The screen of a cable is normally
T
designed to reduce the transfer of electric noise; however, a screen with a lower transfer impedance (Z ) value is more effective than a screen with a
T
higher transfer impedance (Z ).
T
Transfer impedance (Z ) is rarely stated by cable manufacturers but it is often possible to estimate transfer impedance (Z ) by assessing the physical
T T
design of the cable.
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MG.11.B7.02 - VLT ® is a registered Danfoss trademark