Industrial Feeder Protection; Parallel Line Protection - Allen-Bradley Rockwell Automation 857 User Manual

8-2
Applications

Industrial Feeder Protection

Figure 8.2 – Feeder and Motor Devices used in Cable Protection of an Industry Plant Network

Parallel Line Protection

857-UM001A-EN-P – July 2009
Directional earth fault protection and three-phase overcurrent
protection is required in a cable feeder. Furthermore, the thermal
stage can be used to protect the cable against overloading. This
example also includes fast arc protection.
SUPPLY
Figure 8.3 – Feeder and Motor Device Allen-Bradley 857 used for Protection of Parallel Lines
R1
A
B
R2
LOAD/SPARE SUPPLY
R5
LOAD
R3
LOAD
LOAD
R4
LOAD