The good electrical design is more than providing a system that works and more than shifting components on and off particularly when controlled by PAC or PLC controls.
The designer should consider the next accessibility, efficiency and setup costs as a minimum in combination with functionality.
When designing any system it’s important to take into account the system lifecycle of components and the maximum availability without detriment to the gear. Often there’s more than 1 way to wire apart and in many situations, this won’t affect the overall performance, however, this doesn’t imply elements should be thrown together when contemplating a normal motor circuit containing a driveway. Browse http://www.hirelay.com/ for searching more about relay price.
contractor and circuit breaker. It would be possible to wire the machine with the contractor before or after the drive, and the two instances would work however the lifecycle of this driveway will be significantly increased, by fitting the contractor before push and if a failure of a contractor was present could even result in damage the drive.
The above is just 1 example of component general design and produces best practice should be considered down to the recommended fixing torque. There are quite a few different ways which will also increase accessibility; one layout would be presumed the decrease in relays and replacement with solid state devices, as mechanical devices only withstand a maximum number of operations. There are various components on the marketplace which will allow for more reliable switching.