Siemens V20_EN_rev01-08032019.docx
7-4
without the shield connected to earth, as in this case any interference will be greater than with an
unshielded cable.
Any free or unused wires in a multicore cable must be connected to earth at both ends.
7- Any cable, for control or external connections for the shaft and lift car, must never run near and par-
allel to the power cable, even if shielded; if parallel routing cannot be avoided, they must be in sepa-
rate metal raceways.
8- All earth connections must be as short and wide as possible.
9- To avoid unwanted tripping of the differential switch:
Make the power connection as short as possible
Use suitable differential switches (type A or B 300mA)
When possible, reduce the inverter carrier frequency: in fact, as lower is the frequency, is
greater the motor noise, but with less current leakage to earth and less EMC interference; so
the motor windings are less stressed.
