July, 1999

Superior Controls' engineers recently finished a major machine automation project which will allow the Polaroid Corporation to continuously manufacture flat 6 volt camera batteries. This fast track project was successfully completed in less than six months. The new control system involved 91 synchronous drives and more than 2000 machine sensors and actuators (I/O), all of which are automatically monitored and adjusted 200 times per second.

Polaroid has been manufacturing these batteries in Waltham, MA, for many years. Five web lines are continuously and synchronously bonded together with the precise measurement of a chemical slurry inserted between the webs. The original control system, a Unix-based PDP-11/34 system in an assembly-like programming language, was obsolete and difficult to repair. Polaroid hired Superior Controls to design, program, and electrically install a replacement control system.

The software and hardware architecture of the new system was designed to minimize risk and to provide for smooth transition. System startup was scheduled in two major phases- over the long Memorial Day weekend and during the Polaroid summer shutdown. Superior Controls provided a team of electricians who verified and labeled each wire before startup, then completed each electrical changeover within several 20-hour days.

In order to write the new PLC program, Superior Controls' engineers became experts at understanding the old PDP-11 code. After startup was complete, it was a bittersweet moment to see the long line of pallets filled with old PDP equipment headed for recycling. Bill Goff, principal engineer at Polaroid, stated Superior Controls put together an ace team of experienced engineers who knew precisely what needed to be done and was able to overcome every technical obstacle.