An electrician had already replaced the variable frequency drives, with no effect, so the electrician called ACES in on the case. The ACES CSI hooked his laptop up to the machine and noticed right away that one particular output wasn’t coming on. The output was tied to a long string of inputs. There was no documentation to indicate where the inputs were located on the machine. “I thought it must be one of the switches on the input feed table,” said the CSI, “so I pulled my screwdriver out of my pocket and started smacking the switches — and the dryer came to life.”
Sometimes when the glass was advanced into the dryer the ink wasn’t totally dry. A small pin on the microswitch was scratching the ink off, and the ink was then pushed down inside the switch, causing the switch to stick. Consequently, when the CSI tapped the switch it popped up and the dryer took off. This case is a good example of how it often takes a specialist to uncover a small, seemingly simple problem.
The ACES CSI replaced the sticky microswitch and recommended a regular maintenance program to keep the dryer humming in the future.