The use of Programmable Logic Controllers (PLC) for automation of electromechanical processes is an industrial control system technology more and more in use within the fusion community. Traditionally PLC based systems usually are operated and maintained using proprietary SCADA systems (Supervisory Control and Data Acquisition). They are often not integrated with the in house developed control and data acquisition systems. To interface PLCs and thus making the CODAS/CoDaC tools usable for PLC controlled components is an option to bridge this gap. Benefits are: · remote control the PLC from the control room with the same tools as any other control and data acquisition system, ease user interaction · archive PLC data together with the operational and/or physics data · communicate read/write and read only variables, i.e. set points and control variables/measured values At JET an inhouse "black box protocol" approach has been developed to communicate with any external system via a dedicated http based protocol. However, a PLC usually can't be modified to implement this special protocol. Hence, a software layer has been developed that interfaces a PLC by implementing the PLC specific communication part on one side and the black box protocol part on the other side. The software is completely data driven i.e. editing the data structure changes the logic accordingly. It can be tested using the web capability of the black box protocol. Multiple PLC types from different vendors are supported, thus multiple protocols to interface the PLC are in use. Depending on the PLC type and available tools it may or may not necessary to program the PLC accordingly. Wendelstein 7-X uses another approach. For every single PLC a dedicated communication from and to CoDaC is implemented. This communication is projected (programmed) in the PLC and configurable (data driven) on the CoDaC side. The protocol is UDP based and observed via timeout mechanisms. The use of PLCs for Wendelstein 7-X is standardized. Therefore a single implementation on the CoDaC side allows communication with any PLC. Measured data from the PLC is archived in the mass data store. Set points from CoDaC can be visualized from within the PLC visualization environment. A comparison of both approaches and their advantages and disadvantages is given.