Power Distribution - Allen-Bradley 1779-KFMR User Manual

Chapter 4
Installing the 1779 KFM Interface

Power Distribution

4 16
Figure 4.11
Power and Ground Connections
ON
AC POWER
OFF
FUSE
Connect a separate transformer between the AC power source and the
interface power supply to provide DC isolation from other equipment.
Connect the transformer primary to the AC source; connect the high side
of the transformer secondary to the L1 terminal of the power supply;
connect the low side of the transformer secondary to the L2/N terminal of
the power supply.
The power consumed by the 1779-KFM interface is 50W. Multiply the
power requirements of the Allen-Bradley power supplies by 2.5 and add
all other power requirements (input circuits, output circuits) to determine
the required rating of the transformer. The power requirements must take
into consideration the surge currents of devices controlled by the
controller. The minimum transformer rating requirement for the
1779-KFM interface is 125VA.
SLOW BLOW
2A, 250V
115V AC/230V AC
INTERNALLY
SWITCH
SELECTABLE
L1
L2/N
GND
Connect L1 to high side
of transformer.
Connect L2/N to low side
of transformer.
Connect GND post to
central ground bus.