Programmable Logic Controller PLC
To ensure that all components are integrated into a COMPISO System Unit, the unit contains a PLC.
This PLC covers:
- Emergency Off components
- Door contacts connected to the Emergency OFF Logic
- Additional contacts to extend the Emergency Off and CSU Safety Logic to external laboratory equipment
- Additional contacts to integrate the parallel operation of CSU server into a single Emergency Off and safety concept
- Control of internal parameters like cooling water temperature and water pressure
- Control of cabinet signal tower lights to show operating and safety state of the cabinet
- Switching OFF Main Power Switch
- Switching OFF Output Switches
- Discharge DC-Link Capacitors
- Disable Grid Converter and COMPISO Digital Amplifiers
Power ON and Power OFF Logic
Power ON and Power OFF Cycles are triggered by the COMPISO SCADA System. The PLC performs the Power ON Cycle and the Power OFF Cycle. It ensures that the power path is set up in the correct order and that the Digital Amplifiers are put to operation after Power ON Cycle finished. At Power OFF Cycle it disables the Digital Amplifiers first and continues with shut down of all the devices in the power path.
Emergency & Safety Logic
When an Emergency OFF is triggered by pressing an Emergency OFF Button, by opening a cabinets door or triggered by an external event, the safety PLC shuts down the power path, switches off all power devices and discharges the DC-Link capacitors. The safety logic drives the cabinets signal tower to show the COMPISO System Units state.
External Emergency Off
The CSU can be equipped with external contacts to integrate additional emergency off buttons that can be placed outside the COMPISO System Unit. It can be used to integrate laboratory equipment outside the CSU into the safety architecture.
COMPISO System Unit Safety Paralleling
If several CSUs are operated in parallel the safety infrastructures of the CSUs can be connected to work as a single safety cell. To perform this the CSU will be equipped with additional safety cables to connect the safety infrastructure of the CSUs.
The state of water cooling infrastructure is monitored by the PLC Sensors. Furthermore, temperature and pressure are monitored within the SCADA system. If temperature or pressure level leaves the safe operating area, warnings will be sent to the SCADA system. Emergency Power Off gets triggered, as soon as an alarm level exceeds.