New Serial Communications Line Disrupts Network

Event Year: 1997 Reliability: Likely But Unconfirmed
Country: United Kingdom
Industry Type: Food & Beverage
Description:

While a project team was connecting a new serial communication between two PLCs, the main site network connected to the master of these two PLCs was interrupted. Both control and view of the running plant was interrupted. The running plant had its network disconnected while the serial connection was remade.

Impact:

The operator lost visibility of the plant for about 30 minutes.

Action Description: The exact cause was not discovered. The project and production teams developed a procedure so that when new kit was being connected everybody was aware of the situation and the approprite individuals would be available should problems occur.