GE GFK0579B Scanner User Manual


 
2
Series 90–70 Remote I/O Scanner User’s Manual – July 199222
System Grounding Procedures
All components of a control system and the devices it is controlling must be properly
grounded.
Ground conductors should be connected in a tree fashion with branches routed to
a central earth ground point. This ensures that no ground conductor carries
current from any other branch. This method is shown in the figure shown below.
Ground conductors should be as short and as large in size as possible. Braided
straps or ground cables (typically green insulation with a yellow tracer – AWG
#12 or larger) can be used to minimize resistance. Conductors must always be
large enough to carry the maximum short circuit current of the path being
considered.
MOTOR DRIVES
AND
OTHER
ELECTRICAL
CONTROL
EQUIPMENT
MACHINERY
a42942
SERIES 90–70
PLC CABINET
PROGRAMMING
DEVICE
SIGNAL AND POWER
CONNECTIONS
NOT SHOWN
NOTE
EARTH
GROUND
CENTRAL
GROUND POINT
RACK
RACK