Automating Manufacturing Systems - Process Control and ...

plc electrical - 31.4
Once the electrical design is complete, a layout for the controls cabinet is developed,
as shown in Figure 31.2. The physical dimensions of the devices must be considered,
and adequate space is needed to run wires between components. In the cabinet the
AC power would enter at the terminal block, and be connected to the main breaker.It
would then be connected to the contactors and overload relays that constitute the motor
starter. Two of the phases are also connected to the transformer to power the logic. The
start and stop buttons are at the left of the box (note: normally these are mounted elsewhere,
and a separate layout drawing would be needed).
Main
Breaker
Contactors
Overload
Start
Transformer
Stop
Terminal Block
Figure 31.2
A Physical Layout for the Control Cabinet
The final layout in the cabinet might look like the one shown in Figure 31.3.