Rockwell Automation 1772-LV,D17726.6.1 A and I MNL MINI-PLC-2/15 PROCESSO - Manual (Page 37)

Assembly and Installation
Chapter 3
3Ć17
Before installing the keying bands, I/O Module placement with the I/O Chassis
must be determined. A general rule of thumb is to group I/O Modules by signal
type. For field wiring guidelines and considerations, refer to Section titled Field
Wiring Considerations and Field Wiring Guidelines.
System Power Supply
If the side mounting configuration is desired, the System Power Supply and I/O
Chassis should be assembled as a unit before mounting to the enclosure for ease
of assembly. The Power Supply is mounted to the left side plate of the I/O
Chassis with 4 screws.
The Controller components, when mounted, must make solid electrical contact
with the enclosure for grounding purposes. Refer to the text and illustrations in
Section titled PC Component Grounding to ensure that good electrical contact is
established when mounting the components. Figure 3.17 illustrates methods of
mounting the Chassis and connecting the equipment grounding conductor.
CAUTION: Care must be taken not to allow the I/O Chassis to
warp when mounted. This may occur if the back panel is slightly
curved. Chassis distortion can cause stress on the printed circuit
board of the Chassis backplane. This may result in the poor
connection of the I/o modules and their backplane sockets.
To minimize warping, carefully inspect the spacing between the Chassis
mounting brackets and the enclosure back panel with the mounting nuts
hand-tightened. If spaces are uneven, insert flat washers, as needed, onto the
mounting bolts or studs to even the spacing. When this is accomplished,
wrench-tighten the mounting nuts.
In addition to grounding considerations, component spacing and layout
considerations must be observed. If the System Power Supply is to be mounted
as a stand-alone unit, it cannot be mounted below the I/O Chassis.
The I/O Chassis and System Power Supply dimensions for both mounting
configurations are shown in Figure 3.18 through Figure 3.20.
I/O Chassis and Power Supply
Mounting