Rockwell Automation AK DBU - Dynamic Braking Unit 600/690 VAC - Manual (Page 11)

Overview P-7
-
After removing the cover plate of the DBU, a red jumper plug located on
the BUC card allows for the line voltage selection of 690V / 600V.
The selection of this jumper plug defines the DC bus voltage at which
the DBU switches the brake resistor to the DC bus.
Figure P.2 Jumper plug location on the BUC card
Figure P.3 Pulse Width (Jumper Setting) in Relation to DC Bus Voltage
The default jumper voltage selection shipped from the factory is
690V AC line voltage.
Line Voltage Selection
600V
Jumper plug on rear side,
shown in position for 600V AC line
BUC-Card
690V
100%
95%
0% V
DC
Jumper at 600: 913V 950V
690: 1047V 1090V
!
ATTENTION: Without the jumper plug in place, the default line
voltage selection of the DBU is set to 600V AC. When operating on a
690V AC line the brake resistor will be constantly switched on. This
can cause an overtemperature trip on the DBU and/or the brake resistor.
Verify the jumper plug is present and has been properly selected for the
application.