Client: A wholly owned subsidiary of Chinese automaker Geely, London Electric Vehicle Company Limited (erstwhile known as The London Taxi Company) is a leading global manufacturer and retailer of purpose-built taxis with its headquarters located in Coventry, United Kingdom. The company’s newly built electric vehicle manufacturing plant at Ansty (outskirts of Coventry) can produce more than 20,000 vehicles per year, when at full capacity.
Challenge: While expanding the business and production activities, the company was faced with the challenges of improving the efficiency of response to machine-, manufacturing line-, and work process-related production challenges, as well as enhancing production uptime.
Solution: The company invested in an Andon system – a reporting system with color-coded lights indicating the status of any production line challenge – powered by ABB programming logic controllers (PLCs) and human-machine interfaces (HMIs). The system is equipped with audible alarms that enable supervisors or support personnel to report production problems and escalate them until they are solved.
Implementation: One of the notable features of the Andon system is that it provides every manufacturing cite on the production line with a pull cord. Should any incident occur on the line, the attentive staff member can pull the nearest located cord to initiate an alarm signal. Upon detecting the location of the initiated pull for help, the HMIs installed in each production unit will constantly sound an alert and repeatedly flash lights. The alert stays active until concerned people respond to the call. The line gets suspended automatically if the alert does not receive an appropriate response, and the response time to each alert is logged in the system database for subsequent analysis.
Light signals displayed on HMIs direct the nearest response team member to the exact location of the origin of the incident. After carefully evaluating the nature of the incident, whether simple or complicated, the member can take prompt corrective actions ranging from fixing the issue instantly to seeking the help of external departments using HMI, which provides a list of departments that can be contacted for help.
Benefits: Recorded data can later be downloaded and analyzed to determine the time taken to respond to an alert and to assess the number and type of incidents facing each production station. This allows the attending staff members to investigate the factors leading to such incidents and implement effective solutions to prevent recurrence. Reports received from the company sources indicate that installing the Andon system featuring ABB PLCs and HMIs aided the cab maker to reduce the response time to production challenges by up to 33 percent, while maximizing the productivity and equipment uptime considerably.
Keywords: Asset Optimization and Performance Management, ABB PLCs & HMIs, London Electric Vehicle Company Limited, ARC Advisory Group.