Technologies:
- Siemens 1500 series PLC
- WinCC Comfort Pro HMI
- Bosh Conveyance and Pallet Stops
- Simatic MV530 2D Barcode Scanner
- Siemens G115D VFD
Background:
A large industrial equipment manufacturer had an existing, mostly manually operated, production line to build and test high-power breakers. The assembly line was mostly manual and required operators to know where the next station should be. This led to occasional operator errors with breakers going to incorrect stations and on rare occasions, skipping essential stations altogether.
Another challenge of this particular system was the scale and the mobility of the breakers. Each breaker could weigh up to 600 lbs and would potentially need to be lifted and carried to the other side of the warehouse almost 200ft away. Along with an increased risk to operators, the process of manually moving breakers also slowed production time.
For non-related reasons, this company had decided to move to a larger warehouse and decided to completely replace their existing line with a new system of Bosch conveyors.
Approach:
The system was comprised of three basic configurations embedded within the conveyance system:
- A single pallet stop that could hold the breaker in a queue until the next station was ready
- A lift transfer that could send and receive a breaker from any of the four cardinal directions
- A rotate table that could rotate the breakers to their desired orientation before they reached their destinations
In Siemens TIA a function block was created for each of the above processes. Each function block consisted of a state machine to handle sending and receiving from each direction and an interface that allowed each configuration to be linked to the conveyance or station next to it. This architecture allowed us to use only a small amount of code to control a large and repetitive system. Another feature of the architecture was the ability to theoretically send a breaker from any station to any other station and track the pallet through the entire process.
The system also included several other functions. Each station had a WinCC comfort HMI to interact with the conveyance system, control any necessary automation unique to that station, and collect data on the specific processes that were completed. The system was also equipped with barcode scanners that could scan the breakers while entering and after each set of stations. This data was used to determine the next destination and log the completed process.
Final Product:
The completed system was comprised of over 80 VFDs and drives, almost 40 stations with a WinCC comfort HMI, and over 100 pallet stops. The code was comprised of mostly reusable function blocks that helped to expedite system-wide troubleshooting and deployment. The overall cycle time for a single breaker nearly halved while also reducing the physical strain on operators. With the newly added data collection process they are also able to track operator errors and analyze the system for process improvements.
Customer Benefits:
- Fast and easy to deploy code
- Reduced cycle time
- Automated part and data tracking
- Better working conditions for operators