Using the 1-second UPS with several PLC projects on a target system
To use the 1-second UPS with several PLC projects on a target system (PC/CX), please note the following process description.
The process is the same for all supported 1-second UPS devices. Only the SUPS function block for controlling the 1-second UPS is different, depending on the target platform. The PLC runtime systems communicate via process data.
Process description:
- Both PLC runtime systems use their own instance of the SUPS function block to check whether the voltage has failed and then write the persistent data without quick shutdown.
- When the first PLC runtime system has completed the process of writing the persistent data, it notifies the second PLC runtime system.
- The second PLC runtime system also writes the persistent data and at the same time waits for the notification from the first PLC runtime system.
- When both PLC runtime systems have completed the writing process, the second PLC runtime system directly initiates the quick shutdown.
![]() | In configurations with two or more PLC projects, only one PLC runtime system may trigger the quick shutdown. |
Example for CX51x0 Embedded PCs
The example illustrates the application of the 1-second UPS with two PLC projects for 51x0 Embedded PCs.
Download: Sample_SUPS_TwoPlcsTC3.zip