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3BHS212794 E01 REV M
ACS6000
USER MANUAL
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03 POWER ELECTRONICS AND CABINET FEATURES
3.3
Optional cabinet units
The following sections describe the IRU, IFU, VLU, BCU, RBU and EXU
optional cabinet units.
3.3.1
Input reactor unit (IRU)
The IRU is used with the 6-pulse LSU for applications without an
input transformer. The IRU limits the input current and improves the total
harmonic distortion (THD) of the supply voltage.
Figure 3-20 IRU circuit diagram
Figure 3-21 IRU cabinet
(1) IRU
(2) LSU
(3) Thyristor crowbar
(4) Diode rectifier
(5) Snubber circuit
(6) di/dt choke
(1) Three-phase reactor
DC (+)
DC (-)
1L1
1L2
1L3
1
2
3
4
5
6
6
1
1
1