WEG CFW900 - Connection of the Motor Cable Shield to Ground

English
INSTALLATIONANDCONNECTION
PE
SCu
W
U
V
(a)
Symmetricalshieldedcables:threeconcentricconductorswithorwithouta
groundconductor,symmetricallymanufactured,withanexternalshieldofcopper
oraluminum
SCu
PE
PE
PE
U
VW
AFe
PEs
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
o
V
U
W
(b)Alternativeforconductorsupto10mm²
SCu=copperoraluminumexternalshielding.
AFe=steelorgalvanizediron.
PE=groundconductor.
Note1:
Cableshieldingshallbegroundedatbothends(inverterandmotor).Use360ºconnectionsforalowimpedancetohigh-frequencies.
Referto
Figure3.16.
Note2:Forusingtheshieldasaprotectiveground,itshallhaveatleast50%ofthepowercablesconductivity.Otherwise,addanexternal
groundconductorandusetheshieldasanEMCprotection.
Note3:Shieldingconductivityathigh-frequenciesshallbeatleast10%ofthepowercablesconductivity.
Figure3.15:MotorconnectioncablesrecommendedbyIEC60034-25
3.2.4.3.2ConnectionoftheMotorCableShieldtoGround
InvertersoftheCFW900seriesincludeclampsandgroundingplatesthatsimplifytheconnectionofthecontrol
cablesandmotorcableshield,enablingalowimpedanceconnectionforhighfrequencies.
Figure3.16showsan
exampleofmotorcableconnectionusingthesematerialsinaninverterwithIP2Xprotectionrating.Theconnection
oninverterswithULtype1protectionratingissimilar.
Figure3.16:Detailofthemotorcableshieldconnection
36|CFW900