Armature bridge components – Rockwell Automation 1395 Digital DC Drive FRN 5-10.10/9.30 User Manual

Page 43

Chapter 3
Hardware Description
40 – 100 HP, 230VAC

75 – 200 HP, 460VAC

3-3

Armature Bridge Components

A general description of the components in the armature bridge (Figures
3.2 and 3.3) and their operation is detailed here:

AC Line Reactor – When connecting the drive directly to the main
distribution system an AC line reactor must be used to guard against
system disturbance.

When an isolation transformer matched to the unit rating is used, an AC
line reactor is not required.

Fast acting semiconductor fuses F1, F2 and F3 are standard on all drives.

Synchronization – The three-phase input to the drive is tapped and fused
using fuses F4, F5 and F6 (Fig. 3.2) and enters the feedback board. The
feedback board scales down the voltage before being sent to the power
stage interface where it is used to develop the synchronizing information to
be used by the Main Control Board.

AC Current Feedback – Current Transformers ACT-1 and ACT-2
(Figure 3.2) are used to provide current feedback information to the
feedback board. The feedback board rectifies the three-phase feedback and
scales the DC voltage before being sent to the power stage interface. The
DC voltage representing the current feedback is passed directly through the
power stage interface and sent to the main control board.

Figure 3.2
Armature Bridge Components (INPUT)

To Feedback Board

TB1-11, 13, 15 Figure 3.5

To Feedback Board

TB1-5, 6, 7 Figure 3.5

To TB1
Fig. 3.4

Isolation

Transformer

or Line

Reactor

ЗЗЗ

ACT-2

ACT-1

CH2

CH3

CH4

CH5

CH6

CH7

1 MOV

Field
Bridge

AC Current Feedback

Burden Resistor TB2,

Figure 3.5