Eagle Signal MTA330A6 05 What kind of "PLC" or control is this? in Other PLCs Posted 16 April · Edited 16 April by drforsythe missed important info I tried to find some info but could not locate manuals. If you have a model number, it would be helpful. I believe these devices are timers with multiple outputs. In the case of this one, it looks like it has 30 possible outputs and your system has 25 of those outputs wired. As the drum turns, the outputs turn on as the "flags" placed on the drum reach the actuation point (one spot along the drum where the individual switches are placed). This looks like an industrial version of a vacation timer for lights in a home to make it look like people are in the house. To convert this to a PLC, you will need to have or develop a wiring schematic that identifies which switches on the device control what devices on your equipment. Once you have that, you should be able to draw another diagram that identifies the relationship of each switch flag to each other, which will be time-based. If the unit still works and my assumptions are correct, it would be helpful to know how long it takes the drum to rotate one complete revolution. If you know that, you could determine the duration of each of the switches "on" time based on the number of degrees the "flags" cover. From there you could code your PLC based on the relationships you find with your diagrams. I would be really interested in seeing a schematic for your system if you have one. Good luck. That is definitely an interesting piece of early automation. A "keeper" for a collector, for sure! Good luck in your conversion. Please update this post with your findings. After re-reading this, I see you had the model number there the whole time, in plain sight! Sorry about that.