Shielding of cables:
Avoid installation with twisted shield ends (pigtails). They spoil the shielding effect at higher frequencies. If it is necessary to break the shield to install
a motor isolator or motor contactor, the shield must be continued at the lowest possible HF impedance.
Connect the motor cable shield to both the de-coupling plate of the adjustable frequency drive and to the metal housing of the motor.
Make the shield connections with the largest possible surface area (cable clamp). This is done by using the supplied installation devices within the
adjustable frequency drive.
Cable-length and cross-section:
The adjustable frequency drive has been EMC tested with a given length of cable. Keep the motor cable as short as possible to reduce the noise level
and leakage currents.
Switching frequency:
When adjustable frequency drives are used together with sine-wave filters to reduce the acoustic noise from a motor, the switching frequency must be
set according to the instructions in par. 14-01
Switching Frequency
.
Term. no.
96 97 98 99
U V W
PE
1)
Motor voltage 0–100% of AC line voltage.
3 wires out of motor
U1 V1 W1
PE
1)
Delta-connected
W2 U2 V2 6 wires out of motor
U1 V1 W1
PE
1)
Star-connected U2, V2, W2
U2, V2 and W2 to be interconnected separately.
1)Protected Ground Connection
NOTE!
In motors without phase insulation paper or other in-
sulation reinforcement suitable for operation with volt-
age supply (such as a adjustable frequency drive), fit
a sine-wave filter on the output of the adjustable fre-
quency drive.
VLT AQUA High Power Instruction Manual 3 How to Install
MG.20.P3.22 - VLT
®
is a registered Danfoss trademark
3-43
3