4-6
Practices
Figure 4.5 Terminating the Shield with a Pigtail Lead
Pigtail termination is the least effective method of noise containment.
It is not recommended if:
•
the cable length is greater than 1 m (39 in.) or extends beyond the panel
•
in very noisy areas
•
the cables are for very noise sensitive signals (for example, registration
or encoder cables)
•
strain relief is required
If a pigtail is used, pull and twist the exposed shield after separation from
the conductors. Solder a flying lead to the braid to extend its length.
Ground Connections
Ground conductors should be connected with care to assure safe and
adequate connections.
For individual ground connections, star washers and ring lugs should be
used to make connections to mounting plates or other flat surfaces that do
not provide proper compression lugs.
If a ground bus system is used in a cabinet, follow the bus bar mounting
diagrams.
U (T1)
V (T2)
W (T3)
PE
PE
Flying lead soldered to braid
Exposed shield
Important:
This is an acceptable industry practice for most installations.
to minimize stray common mode currents
Summary of Contents for Allen-Bradley 1305-AA02A
Page 4: ...ii Summary of Changes Notes ...
Page 40: ...2 18 Power Distribution Notes ...
Page 48: ...3 8 Grounding Notes ...
Page 68: ...4 20 Practices Notes ...
Page 78: ...6 8 Electromagnetic Interference Notes ...
Page 94: ...Glossary 4 UL Underwriters Laboratories ...
Page 100: ...Index 6 ...
Page 101: ......