A PLC TEST BENCH AT ESS

The European Spallation Source (ESS) is an acceleratordriven neutron spallation source. The Integrated Controls Systems (ICS) is responsible for providing control and monitoring for all parts of the machine (accelerator, target, neutron scattering systems and conventional facilities) [1]. A large number of applications have been identified across all parts of the facility where PLCs will be used: cryogenics, vacuum, water-cooling, power systems, safety and protection systems. The Controls Division at ESS is deploying a PLC Test Bench. The motivation is to evaluate different technologies, to test PLCs and their integration into EPICS, to prototype control systems and use the test bench as PLC software development platform. This report defines the architecture of this infrastructure. The first stage to procure a first set of hardware and to perform initial tests has already been finished, consisting of a comparison between the performance of the s7plc EPICS driver and the Modbus EPICS driver. The results of these tests are discussed and future plans for this infrastructure are presented.