I work at a manufacturing plant (in software engineering) and we have 3rd party hardware and software that monitors industrial machinery (primarily speeds).
For training and testing we need to be able to emulate one of the machines. The 3rd party hardware is based on the Omron CP1L-EM30DT1-D PLC - (http://datasheet.octopart.com/CP1L-EM30DT1-D-Omron-datasheet-12510914.pdf)
I was going to build something simple using a variable speed DC motor and encoder wheel to generate pulses, but then it dawned on me, can't I just use an arduino and software to send variable frequency pulses? It doesn't need to be very accurate. We'd probably want a range of 1,000 to 60,000 per hour.
I'll admit that I know nothing about PLC's (yet), so I'm looking for guidance.
What would I need to send pulses to this PLC from the arduino (I'm assuming I need 24v DC so would have to switch that via a relay)? I'm trying to get some information from our vendor too. They said I could do something simple with a push button (but I'm trying to get more info). Not sure if this would help determine what I need to do.
Initially, I'll use constants in the sketch to set the speed on startup, but long term, I'd add some kind of speed control using a rotary switch or pot and hard buttons for stop and start.
Thanks in advance