Danfoss VLT AQUA Drive FC 202 Design Manual page 137

How to Install
A
* F10/F11/F12/F13 Only
R1
S1
T1
R2
S2
T2
B
* F10/F11/F12/F13 Only
R1
S1
T1
R2
S2
T2
C
Illustration 5.91
1), 2), 3)
A) 6-Pulse Connection
B) Modified 6-Pulse Connection
3), 5)
C) 12-Pulse Connection
Notes:
1)
Parallel connection shown. A single three-phase cable
may be used with sufficient carrying capability. Shorting
bus bars must be installed.
2)
6-pulse connection eliminates the harmonics reduction
benefits of the 12-pulse rectifier.
3)
Suitable for IT and TN mains connection.
4) In the unlikely event that one of the 6-pulse modular
rectifiers becomes inoperable, it is possible to operate the
frequency converter at reduced load with a single 6-pulse
rectifier. Contact the factory for reconnection details.
®
VLT AQUA Drive FC 202 Design Guide
91-1
Recti er 1
92-1
93-1
91-2
Recti er 2
92-2
93-2
95
91-1
Recti er 1
92-1
93-1
91-2
Recti er 2
92-2
93-2
95
91-1
Recti er 1
92-1
93-1
91-2
Recti er 2
92-2
93-2
95
2), 3), 4)
®
MG20Z102 - VLT is a registered Danfoss trademark
5)
No paralleling of mains cabling is shown here. 12 pulse
as a 6 pulse should have mains cable requirements of
equal number of cables and lengths.
NOTE
Mains cables should be equal length (±10%) and the same
wire size for all three phases on both rectifier sections. A
12 pulse frequency converter used as a 6 pulse should
have mains cables of equal numbers and lengths.
Screening of cables
Avoid installation with twisted screen ends (pigtails). They
spoil the screening effect at higher frequencies. If it is
necessary to break the screen to install a motor isolator or
5 5
135