A bespoke phase locking system
An embossing line was controlled by old analog GEC single phase drives and a huge rack of obsolete analog cards for diameter and pid control, section control and trim control features. A bespoke phase locking system was also used on one section to accurately control the embossing process. The plc was an S7 Siemens system. A survey was carried out on the line and after ruling out various makes of drive due to the tight space limitations within the existing panels, the whole drive system comprising of 22 drives was replaced using Sprint electric Digital dc drives with an Ethernet option. These option cards have multi master software blocks inside programmed using “Savvy” software from Bardac in the USA. This allowed all of the features on the analog cards to be copied in software on the Ethernet network, a Ethernet based io module with phase locking software built in was also utilised on the network.
To keep the costs down for the customer there own electricians were used in the installation and retrofitting process and the project was installed around the clock by using 2 teams working 12 hour shifts managed by Oracle Drive Systems.
Due to the panels being situated well away from any of the operator control desks, a wireless access point was installed to allow 1 man to commission by walking around the machine with a laptop running the drive Ethernet based software and testing all of the digital and analogue io signals.