Backplane Earth Rails; Backplane Electrical Connections - Eaton Crouse-Hinds Series Instruction Manual

8
DRAFT - 22 March 2018
4 .3

Backplane earth rails

Optional earth rails are available for 8- and 16-way backplanes (kits ERK08 and ERK16
respectively). Cable screens from hazardous-area circuits, or spare pairs from a multicore
cable, can be connected to the terminals on the earth rails, which are mounted on the
backplane at about the same height as the front of the modules, close to the hazardous-
area connectors. Proceed as follows.
4 .3 .1 Earth rail kit (ERK08 and ERK16)
See Figures 4.1 and 4.8.
a) Locate the earth rail mounting posts (1) at backplane centres C (Figures 4.1 and 4.8).
b) Attach the mounting posts (1) with M3 x 12 screws (3) and washers (4).
c) Slide the earth rail (5) through the slots in the of the mounting posts (1).
d) Fit the earth terminal(s) (6) on the rail (5).
e) Attach plastic retaining rivets (7) to each end of the earth rail (5).
Earth rail
post (1)
ERK locating holes ‘C’
4 .4

Backplane electrical connections

Safe-area circuit connections are made to the backplane by fixed screw-clamp terminals.
Power supply connections are also made to the backplanes via pluggable screw-terminal
connectors.
For optimum EMC performance, cables from local power supplies should not exceed 10m
in length.
See section 4.4.2 for details, section 4.4.3 for a procedure to interconnect power supplies
on multiple 8- and 16-way backplanes, and section 4.4.4 for details of connecting power
supplies on
24-way backplanes.
4 .4 .1 Making connections
a) Trim back the insulation of conductors by 12mm.
b) Check the terminal assignments shown in section 6 or on the side label of the unit.
c) Insert conductors according to the terminal assignments and tighten screws. Torque
range 0.4Nm to 0.6Nm.
If the wires are to be fitted with crimp ferrules, the following is a list of those recommended
with required trim lengths for each:
Plug Entry Wire size
type (mm 2 )
Signal Single 0.75
Signal Single 1.0
Signal Single 1.0
Signal Single 1.5
Signal Single 2.5
Power Twin 2x0.75
Power Twin 2x0.75
Power Twin 2x1.0
Power Single 0.75
Power Single 1.0
† These ferrules with 18mm length metal tubes should be cut to 12mm after crimping
Note: Smaller section wire than that stated can often be successfully used if the crimping is good.
Crimp tool: Phoenix Contact Crimpfox UD6 part number 1204436
Earth rail
post (1)
M3x12mm
screw (3)
Washer
Backplane
(4)
(2)
C C
Figure 4 .8: Earth rail post kit details
Recommended ferrules
Metal tube Trim
length (mm) length
Weidmuller 902591
12 14
12 14 Cembre PKC112
Phoenix Contact
12 14
AI 1-12 RD (3200674)
12 14 Cembre PKE1518†
Cembre PKE2518†
12 14
10 12 Cembre PKET7510
10 12 AMP (non-preferred) 966144-5
Phoenix Contact AI-TWIN 2X 1-10 RD
10 12
10 12 AMP 966067-0
10 12 Phoenix Contact AI 1-10 RD
Plastic
retaining Earth
rivets (7) terminals (6)
Earth
rail (5)
INM 4500/4600 Rev 12